pilot adjustment

classic Classic list List threaded Threaded
18 messages Options
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

pilot adjustment

William Hall
Here is a link and the verbage for setting the pilot. Does this sound good for our bikes? Seems like I remember the factory setting was 2.5 turns. What do you think? I got my ais removed and everything capped and now there is only a slight backfire at idle. With the Mikunis it's a pain to get at the screws. Does anyone use a 90 degree screwdriver and if so where did you get it and how much and des it reach both screw. Thanks, Mike
 
This is my prefered method of finding the proper setting for the pilot screw (aka fuel screw). This method can also indicate if your pilot jet is too big or too small. Towards the bottom is an explination about the difference between fuel screws and air screws.

You'll need to be able to access the fuel screw while the engine is running. This can be quite difficult on many carbs. FCRs have aftermarket fuel screws that are longer which helps. On a stock 400EX carb (and many others) I use a 90 degree screwdriver. I bit the bullet and bought this one from MotionPro. It works well but I'm sure there are others available. If you're lucky, your fuel screw is easily reached with a normal screw driver.

http://www.azjetski.com/catalog/images/03MotionProPilotAdjustSM.gif

OK. On to the procedure!

1) Warm up the engine to full operating temp.

2) Turn up your idle a few hundred RPM using the throttle stop screw (basically you want a fast idle). This will make it easier to hear small changes in RPM. Watch for overheating--pointing a big shop fan at your engine will help it from getting too hot during the fast idling. The whole procedure shouldn't take too long though.

Each time you change the screw setting 1/4 or 1/2 turn or so, wait about 5 seconds to let the idle speed normalize. It usually take the carb and engine a moment to react to the change.

3) Turn the fuel screw IN until the idle starts to drop and miss. The engine should die if you bottom out the screw. Your pilot jet is too big if it doesn't die when the screw is bottomed out--it should die before it gets that far in.

4) Then begin turning the fuel screw OUT. The idle should peak and become smooth. Keep going and look for the idle to begin to drop/miss again.

5) The goal is to find the setting that provides the highest and smoothest idle. If it's unclear exactly were that point is then set to the midpoint between step #3 and step #4. For example, if the idle starts to drop at 1 turn out and starts to drop at 2 1/2 turns out then 1 3/4 of a turn out should be the correct setting.

If the peak/smoothest RPM is reached somewhere between 1-3 turns then your pilot jet is correct (the 1-3 turns applies to most carb types). If you end up less than 1 turn out then your pilot jet is too big and you need a smaller one. If you end up more than three turns out or the fuel screw seems to make little difference as you continue turning it out than you need to go up (bigger) on your pilot jet.

To re-emphisize: If the idle never drops when you're turning the fuel screw in, you need a smaller pilot jet. If the idle never drops when you're turning the fuel screw out, you need a bigger pilot jet.

Typical fuel screw settings are in the 1 1/2 to 2 1/2 range.

6) Once you've got the fuel screw set, re-adjust your throttle stop screw (idle screw) to an appropriate idle speed.

And that's it! Your pilot circuit is now VERY close to ideal. From here you can experiment with how small adjustments affect low-end (i.e. small throttle openings) response and make adjustments for weather. The hardest part is usually gaining access to the screw while the engine is running. Also, you may really have to listen carefully to detect the rpm changes in the idle. 100 or 200 rpm differences can be tough to detect when the change happens over several seconds.http://www.exriders.com/archive/topic/229923-1.html
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: pilot adjustment

bill.stigall
Bill,
The base setting is 2.5 turns out from a soft seat. Every bike is different, so you have to adjust each carb until you get the best idle. In is leaner; out is richer.......... As for the procedure; it is a good general procedure with the exception of adjusting the idle speed and the jet size..... On the Virago you need to consider the sync of the carbs if you try and adjust the idle speed. Hitachi's are individually adjustable for idle speed, I am not sure about Mikuni's. If you adjust your idle up, you may have to re-sync your carbs. The turn the pilot screw all the way in, make sure you don't tighten it down tight or it will damage both the needle and the seat. On a single cylinder engine, it might die when you lean it out, but that isn't necessarily true on a twin, it should slow the idle and perhaps start hitting on one cylinder. A better read on if you are running to rich or too lean it the color of your spark plugs.
The offset screw driver is a good idea. Also a flexible screwdriver will work as well. The pilot screws are on top of the carb throat in the Mikuni carb, so you will have to raise the fuel tank or remove it and use a bottle with some fuel in it and a hose connected to the carbs. The latter is the easier way IMHO.

Bill
  ----- Original Message -----
  From: William Hall
  To: [hidden email]
  Sent: Sunday, May 09, 2010 7:49 AM
  Subject: [ViragoTech] pilot adjustment


   
        Here is a link and the verbage for setting the pilot. Does this sound good for our bikes? Seems like I remember the factory setting was 2.5 turns. What do you think? I got my ais removed and everything capped and now there is only a slight backfire at idle. With the Mikunis it's a pain to get at the screws. Does anyone use a 90 degree screwdriver and if so where did you get it and how much and des it reach both screw. Thanks, Mike

        This is my prefered method of finding the proper setting for the pilot screw (aka fuel screw). This method can also indicate if your pilot jet is too big or too small. Towards the bottom is an explination about the difference between fuel screws and air screws.

        You'll need to be able to access the fuel screw while the engine is running. This can be quite difficult on many carbs. FCRs have aftermarket fuel screws that are longer which helps. On a stock 400EX carb (and many others) I use a 90 degree screwdriver. I bit the bullet and bought this one from MotionPro. It works well but I'm sure there are others available. If you're lucky, your fuel screw is easily reached with a normal screw driver.

        http://www.azjetski.com/catalog/images/03MotionProPilotAdjustSM.gif

        OK. On to the procedure!

        1) Warm up the engine to full operating temp.

        2) Turn up your idle a few hundred RPM using the throttle stop screw (basically you want a fast idle). This will make it easier to hear small changes in RPM. Watch for overheating--pointing a big shop fan at your engine will help it from getting too hot during the fast idling. The whole procedure shouldn't take too long though.

        Each time you change the screw setting 1/4 or 1/2 turn or so, wait about 5 seconds to let the idle speed normalize. It usually take the carb and engine a moment to react to the change.

        3) Turn the fuel screw IN until the idle starts to drop and miss. The engine should die if you bottom out the screw. Your pilot jet is too big if it doesn't die when the screw is bottomed out--it should die before it gets that far in.

        4) Then begin turning the fuel screw OUT. The idle should peak and become smooth. Keep going and look for the idle to begin to drop/miss again.

        5) The goal is to find the setting that provides the highest and smoothest idle. If it's unclear exactly were that point is then set to the midpoint between step #3 and step #4. For example, if the idle starts to drop at 1 turn out and starts to drop at 2 1/2 turns out then 1 3/4 of a turn out should be the correct setting.

        If the peak/smoothest RPM is reached somewhere between 1-3 turns then your pilot jet is correct (the 1-3 turns applies to most carb types). If you end up less than 1 turn out then your pilot jet is too big and you need a smaller one. If you end up more than three turns out or the fuel screw seems to make little difference as you continue turning it out than you need to go up (bigger) on your pilot jet.

        To re-emphisize: If the idle never drops when you're turning the fuel screw in, you need a smaller pilot jet. If the idle never drops when you're turning the fuel screw out, you need a bigger pilot jet.

        Typical fuel screw settings are in the 1 1/2 to 2 1/2 range.

        6) Once you've got the fuel screw set, re-adjust your throttle stop screw (idle screw) to an appropriate idle speed.

        And that's it! Your pilot circuit is now VERY close to ideal. From here you can experiment with how small adjustments affect low-end (i.e. small throttle openings) response and make adjustments for weather. The hardest part is usually gaining access to the screw while the engine is running. Also, you may really have to listen carefully to detect the rpm changes in the idle. 100 or 200 rpm differences can be tough to detect when the change happens over several seconds.http://www.exriders.com/archive/topic/229923-1.html 


 
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: pilot adjustment

William Hall
I've got Mikunis. I did this years ago on my 86-1100 and it never died even all the way in and I don't think it did much all the way out either but I'm gonna play with it. I forget, how do you turn the idele up on MIkunis? I had put them on my 86 when I removed my KJS single carb. Thanks, Mike

--- On Sun, 5/9/10, Bill's Personal <[hidden email]> wrote:Bill,





The base setting is 2.5 turns out from a soft seat. Every bike is different, so you have to adjust each carb until you get the best idle. In is leaner; out is richer...... .... As for the procedure; it is a good general procedure with the exception of adjusting the idle speed and the jet size..... On the Virago you need to consider the sync of the carbs if you try and adjust the idle speed. Hitachi's are individually adjustable for idle speed, I am not sure about Mikuni's. If you adjust your idle up, you may have to re-sync your carbs. The turn the pilot screw all the way in, make sure you don't tighten it down tight or it will damage both the needle and the seat. On a single cylinder engine, it might die when you lean it out, but that isn't necessarily true on a twin, it should slow the idle and perhaps start hitting on one cylinder. A better read on if you are running to rich or too lean it the color of your spark plugs.
The offset screw driver is a good idea. Also a flexible screwdriver will work as well. The pilot screws are on top of the carb throat in the Mikuni carb, so you will have to raise the fuel tank or remove it and use a bottle with some fuel in it and a hose connected to the carbs. The latter is the easier way IMHO.
 
Bill

----- Original Message -----
From: William Hall
To: ViragoTech@yahoogro ups.com
Sent: Sunday, May 09, 2010 7:49 AM
Subject: [ViragoTech] pilot adjustment

 






Here is a link and the verbage for setting the pilot. Does this sound good for our bikes? Seems like I remember the factory setting was 2.5 turns. What do you think? I got my ais removed and everything capped and now there is only a slight backfire at idle. With the Mikunis it's a pain to get at the screws. Does anyone use a 90 degree screwdriver and if so where did you get it and how much and des it reach both screw. Thanks, Mike
 
This is my prefered method of finding the proper setting for the pilot screw (aka fuel screw). This method can also indicate if your pilot jet is too big or too small. Towards the bottom is an explination about the difference between fuel screws and air screws.

You'll need to be able to access the fuel screw while the engine is running. This can be quite difficult on many carbs. FCRs have aftermarket fuel screws that are longer which helps. On a stock 400EX carb (and many others) I use a 90 degree screwdriver. I bit the bullet and bought this one from MotionPro. It works well but I'm sure there are others available. If you're lucky, your fuel screw is easily reached with a normal screw driver.

http://www.azjetski .com/catalog/ images/03MotionP roPilotAdjustSM. gif

OK. On to the procedure!

1) Warm up the engine to full operating temp.

2) Turn up your idle a few hundred RPM using the throttle stop screw (basically you want a fast idle). This will make it easier to hear small changes in RPM. Watch for overheating- -pointing a big shop fan at your engine will help it from getting too hot during the fast idling. The whole procedure shouldn't take too long though.

Each time you change the screw setting 1/4 or 1/2 turn or so, wait about 5 seconds to let the idle speed normalize. It usually take the carb and engine a moment to react to the change.

3) Turn the fuel screw IN until the idle starts to drop and miss. The engine should die if you bottom out the screw. Your pilot jet is too big if it doesn't die when the screw is bottomed out--it should die before it gets that far in.

4) Then begin turning the fuel screw OUT. The idle should peak and become smooth. Keep going and look for the idle to begin to drop/miss again.

5) The goal is to find the setting that provides the highest and smoothest idle. If it's unclear exactly were that point is then set to the midpoint between step #3 and step #4. For example, if the idle starts to drop at 1 turn out and starts to drop at 2 1/2 turns out then 1 3/4 of a turn out should be the correct setting.

If the peak/smoothest RPM is reached somewhere between 1-3 turns then your pilot jet is correct (the 1-3 turns applies to most carb types). If you end up less than 1 turn out then your pilot jet is too big and you need a smaller one. If you end up more than three turns out or the fuel screw seems to make little difference as you continue turning it out than you need to go up (bigger) on your pilot jet.

To re-emphisize: If the idle never drops when you're turning the fuel screw in, you need a smaller pilot jet. If the idle never drops when you're turning the fuel screw out, you need a bigger pilot jet.

Typical fuel screw settings are in the 1 1/2 to 2 1/2 range.

6) Once you've got the fuel screw set, re-adjust your throttle stop screw (idle screw) to an appropriate idle speed.

And that's it! Your pilot circuit is now VERY close to ideal. From here you can experiment with how small adjustments affect low-end (i.e. small throttle openings) response and make adjustments for weather. The hardest part is usually gaining access to the screw while the engine is running. Also, you may really have to listen carefully to detect the rpm changes in the idle. 100 or 200 rpm differences can be tough to detect when the change happens over several seconds.http://www.exriders .com/archive/ topic/229923- 1.html




Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: pilot adjustment

William Hall
Well I set them both at 3 and no more backfire. I cleaned the plugs so after a bit of ridin I'll check them again. nstead of raising the rear of the gas tank I raised the front and it gave as much clearance as possible with the frame and wires in the way.Thanks, Mike

--- On Sun, 5/9/10, William Hall <[hidden email]> wrote:


From: William Hall <[hidden email]>
Subject: Re: [ViragoTech] pilot adjustment
To: [hidden email]
Date: Sunday, May 9, 2010, 10:37 AM


 







I've got Mikunis. I did this years ago on my 86-1100 and it never died even all the way in and I don't think it did much all the way out either but I'm gonna play with it. I forget, how do you turn the idele up on MIkunis? I had put them on my 86 when I removed my KJS single carb. Thanks, Mike

--- On Sun, 5/9/10, Bill's Personal <bill.stigall@ sbcglobal. net> wrote:Bill,





The base setting is 2.5 turns out from a soft seat. Every bike is different, so you have to adjust each carb until you get the best idle. In is leaner; out is richer...... .... As for the procedure; it is a good general procedure with the exception of adjusting the idle speed and the jet size..... On the Virago you need to consider the sync of the carbs if you try and adjust the idle speed. Hitachi's are individually adjustable for idle speed, I am not sure about Mikuni's. If you adjust your idle up, you may have to re-sync your carbs. The turn the pilot screw all the way in, make sure you don't tighten it down tight or it will damage both the needle and the seat. On a single cylinder engine, it might die when you lean it out, but that isn't necessarily true on a twin, it should slow the idle and perhaps start hitting on one cylinder. A better read on if you are running to rich or too lean it the color of your spark plugs.
The offset screw driver is a good idea. Also a flexible screwdriver will work as well. The pilot screws are on top of the carb throat in the Mikuni carb, so you will have to raise the fuel tank or remove it and use a bottle with some fuel in it and a hose connected to the carbs. The latter is the easier way IMHO.
 
Bill

----- Original Message -----
From: William Hall
To: ViragoTech@yahoogro ups.com
Sent: Sunday, May 09, 2010 7:49 AM
Subject: [ViragoTech] pilot adjustment

 






Here is a link and the verbage for setting the pilot. Does this sound good for our bikes? Seems like I remember the factory setting was 2.5 turns. What do you think? I got my ais removed and everything capped and now there is only a slight backfire at idle. With the Mikunis it's a pain to get at the screws. Does anyone use a 90 degree screwdriver and if so where did you get it and how much and des it reach both screw. Thanks, Mike
 
This is my prefered method of finding the proper setting for the pilot screw (aka fuel screw). This method can also indicate if your pilot jet is too big or too small. Towards the bottom is an explination about the difference between fuel screws and air screws.

You'll need to be able to access the fuel screw while the engine is running. This can be quite difficult on many carbs. FCRs have aftermarket fuel screws that are longer which helps. On a stock 400EX carb (and many others) I use a 90 degree screwdriver. I bit the bullet and bought this one from MotionPro. It works well but I'm sure there are others available. If you're lucky, your fuel screw is easily reached with a normal screw driver.

http://www.azjetski .com/catalog/ images/03MotionP roPilotAdjustSM. gif

OK. On to the procedure!

1) Warm up the engine to full operating temp.

2) Turn up your idle a few hundred RPM using the throttle stop screw (basically you want a fast idle). This will make it easier to hear small changes in RPM. Watch for overheating- -pointing a big shop fan at your engine will help it from getting too hot during the fast idling. The whole procedure shouldn't take too long though.

Each time you change the screw setting 1/4 or 1/2 turn or so, wait about 5 seconds to let the idle speed normalize. It usually take the carb and engine a moment to react to the change.

3) Turn the fuel screw IN until the idle starts to drop and miss. The engine should die if you bottom out the screw. Your pilot jet is too big if it doesn't die when the screw is bottomed out--it should die before it gets that far in.

4) Then begin turning the fuel screw OUT. The idle should peak and become smooth. Keep going and look for the idle to begin to drop/miss again.

5) The goal is to find the setting that provides the highest and smoothest idle. If it's unclear exactly were that point is then set to the midpoint between step #3 and step #4. For example, if the idle starts to drop at 1 turn out and starts to drop at 2 1/2 turns out then 1 3/4 of a turn out should be the correct setting.

If the peak/smoothest RPM is reached somewhere between 1-3 turns then your pilot jet is correct (the 1-3 turns applies to most carb types). If you end up less than 1 turn out then your pilot jet is too big and you need a smaller one. If you end up more than three turns out or the fuel screw seems to make little difference as you continue turning it out than you need to go up (bigger) on your pilot jet.

To re-emphisize: If the idle never drops when you're turning the fuel screw in, you need a smaller pilot jet. If the idle never drops when you're turning the fuel screw out, you need a bigger pilot jet.

Typical fuel screw settings are in the 1 1/2 to 2 1/2 range.

6) Once you've got the fuel screw set, re-adjust your throttle stop screw (idle screw) to an appropriate idle speed.

And that's it! Your pilot circuit is now VERY close to ideal. From here you can experiment with how small adjustments affect low-end (i.e. small throttle openings) response and make adjustments for weather. The hardest part is usually gaining access to the screw while the engine is running. Also, you may really have to listen carefully to detect the rpm changes in the idle. 100 or 200 rpm differences can be tough to detect when the change happens over several seconds.http://www.exriders .com/archive/ topic/229923- 1.html




Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: pilot adjustment

bill.stigall
As you are probably aware, the plug color should be tan or both cylinders. If they are black, you will need to lean that carb out a little. Try 1/4 turn at a time and then run it again. If the plug color is white, then you will need to turn the pilot screw out and try again. The color may be different on each cylinder. On Mikuni carbs, the pilot jet handles idle and low speed, however when the engine speed picks up, the pilot jet is wide open and works in combination with the main jet to get the mixture for higher engine speeds. Therefore minor adjustments in high speed mixture can be made with the pilot screw.
Once you have both carbs running with the correct mixture, (plug color tan on both cylinders), you should be good to go. Have patience, this can take a little while to get them dialed in.

Bill

  ----- Original Message -----
  From: William Hall
  To: [hidden email]
  Sent: Sunday, May 09, 2010 5:50 PM
  Subject: Re: [ViragoTech] pilot adjustment


   
        Well I set them both at 3 and no more backfire. I cleaned the plugs so after a bit of ridin I'll check them again. nstead of raising the rear of the gas tank I raised the front and it gave as much clearance as possible with the frame and wires in the way.Thanks, Mike

        --- On Sun, 5/9/10, William Hall <[hidden email]> wrote:


          From: William Hall <[hidden email]>
          Subject: Re: [ViragoTech] pilot adjustment
          To: [hidden email]
          Date: Sunday, May 9, 2010, 10:37 AM


           
                I've got Mikunis. I did this years ago on my 86-1100 and it never died even all the way in and I don't think it did much all the way out either but I'm gonna play with it. I forget, how do you turn the idele up on MIkunis? I had put them on my 86 when I removed my KJS single carb. Thanks, Mike

                --- On Sun, 5/9/10, Bill's Personal <bill.stigall@ sbcglobal. net> wrote:Bill,
                  The base setting is 2.5 turns out from a soft seat. Every bike is different, so you have to adjust each carb until you get the best idle. In is leaner; out is richer...... .... As for the procedure; it is a good general procedure with the exception of adjusting the idle speed and the jet size..... On the Virago you need to consider the sync of the carbs if you try and adjust the idle speed. Hitachi's are individually adjustable for idle speed, I am not sure about Mikuni's. If you adjust your idle up, you may have to re-sync your carbs. The turn the pilot screw all the way in, make sure you don't tighten it down tight or it will damage both the needle and the seat. On a single cylinder engine, it might die when you lean it out, but that isn't necessarily true on a twin, it should slow the idle and perhaps start hitting on one cylinder. A better read on if you are running to rich or too lean it the color of your spark plugs.
                  The offset screw driver is a good idea. Also a flexible screwdriver will work as well. The pilot screws are on top of the carb throat in the Mikuni carb, so you will have to raise the fuel tank or remove it and use a bottle with some fuel in it and a hose connected to the carbs. The latter is the easier way IMHO.

                  Bill
                    ----- Original Message -----
                    From: William Hall
                    To: ViragoTech@yahoogro ups.com
                    Sent: Sunday, May 09, 2010 7:49 AM
                    Subject: [ViragoTech] pilot adjustment


                     
                          Here is a link and the verbage for setting the pilot. Does this sound good for our bikes? Seems like I remember the factory setting was 2.5 turns. What do you think? I got my ais removed and everything capped and now there is only a slight backfire at idle. With the Mikunis it's a pain to get at the screws. Does anyone use a 90 degree screwdriver and if so where did you get it and how much and des it reach both screw. Thanks, Mike

                          This is my prefered method of finding the proper setting for the pilot screw (aka fuel screw). This method can also indicate if your pilot jet is too big or too small. Towards the bottom is an explination about the difference between fuel screws and air screws.

                          You'll need to be able to access the fuel screw while the engine is running. This can be quite difficult on many carbs. FCRs have aftermarket fuel screws that are longer which helps. On a stock 400EX carb (and many others) I use a 90 degree screwdriver. I bit the bullet and bought this one from MotionPro. It works well but I'm sure there are others available. If you're lucky, your fuel screw is easily reached with a normal screw driver.

                          http://www.azjetski .com/catalog/ images/03MotionP roPilotAdjustSM. gif

                          OK. On to the procedure!

                          1) Warm up the engine to full operating temp.

                          2) Turn up your idle a few hundred RPM using the throttle stop screw (basically you want a fast idle). This will make it easier to hear small changes in RPM. Watch for overheating- -pointing a big shop fan at your engine will help it from getting too hot during the fast idling. The whole procedure shouldn't take too long though.

                          Each time you change the screw setting 1/4 or 1/2 turn or so, wait about 5 seconds to let the idle speed normalize. It usually take the carb and engine a moment to react to the change.

                          3) Turn the fuel screw IN until the idle starts to drop and miss. The engine should die if you bottom out the screw. Your pilot jet is too big if it doesn't die when the screw is bottomed out--it should die before it gets that far in.

                          4) Then begin turning the fuel screw OUT. The idle should peak and become smooth. Keep going and look for the idle to begin to drop/miss again.

                          5) The goal is to find the setting that provides the highest and smoothest idle. If it's unclear exactly were that point is then set to the midpoint between step #3 and step #4. For example, if the idle starts to drop at 1 turn out and starts to drop at 2 1/2 turns out then 1 3/4 of a turn out should be the correct setting.

                          If the peak/smoothest RPM is reached somewhere between 1-3 turns then your pilot jet is correct (the 1-3 turns applies to most carb types). If you end up less than 1 turn out then your pilot jet is too big and you need a smaller one. If you end up more than three turns out or the fuel screw seems to make little difference as you continue turning it out than you need to go up (bigger) on your pilot jet.

                          To re-emphisize: If the idle never drops when you're turning the fuel screw in, you need a smaller pilot jet. If the idle never drops when you're turning the fuel screw out, you need a bigger pilot jet.

                          Typical fuel screw settings are in the 1 1/2 to 2 1/2 range.

                          6) Once you've got the fuel screw set, re-adjust your throttle stop screw (idle screw) to an appropriate idle speed.

                          And that's it! Your pilot circuit is now VERY close to ideal. From here you can experiment with how small adjustments affect low-end (i.e. small throttle openings) response and make adjustments for weather. The hardest part is usually gaining access to the screw while the engine is running. Also, you may really have to listen carefully to detect the rpm changes in the idle. 100 or 200 rpm differences can be tough to detect when the change happens over several seconds.http://www.exriders .com/archive/ topic/229923- 1.html
               
       


 
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

The forum is experiencing problems

ms8238
In reply to this post by William Hall
The forum is experiencing problems, but our host is working with us to resolve them.

So you may see the error page more often. Click the back button and ignore it.


1 bug now is posting links in the quick reply box sends you to it.
Remove the http:// part and it will go through.

The quick reply box will be up n down, so if you don't see it, don't panic.
I got it removed right now.
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: pilot adjustment

William Hall
In reply to this post by bill.stigall
Ahh yes patience, sometimes thats had to come by. But I will try. Thanks, Mike

--- On Sun, 5/9/10, Bill's Personal <[hidden email]> wrote:


From: Bill's Personal <[hidden email]>
Subject: Re: [ViragoTech] pilot adjustment
To: [hidden email]
Date: Sunday, May 9, 2010, 9:30 PM


 




As you are probably aware, the plug color should be tan or both cylinders. If they are black, you will need to lean that carb out a little. Try 1/4 turn at a time and then run it again. If the plug color is white, then you will need to turn the pilot screw out and try again. The color may be different on each cylinder. On Mikuni carbs, the pilot jet handles idle and low speed, however when the engine speed picks up, the pilot jet is wide open and works in combination with the main jet to get the mixture for higher engine speeds. Therefore minor adjustments in high speed mixture can be made with the pilot screw.
Once you have both carbs running with the correct mixture, (plug color tan on both cylinders), you should be good to go. Have patience, this can take a little while to get them dialed in.
 
Bill
 

----- Original Message -----
From: William Hall
To: ViragoTech@yahoogro ups.com
Sent: Sunday, May 09, 2010 5:50 PM
Subject: Re: [ViragoTech] pilot adjustment

 





Well I set them both at 3 and no more backfire. I cleaned the plugs so after a bit of ridin I'll check them again. nstead of raising the rear of the gas tank I raised the front and it gave as much clearance as possible with the frame and wires in the way.Thanks, Mike

--- On Sun, 5/9/10, William Hall <wmh1968@att. net> wrote:


From: William Hall <wmh1968@att. net>
Subject: Re: [ViragoTech] pilot adjustment
To: ViragoTech@yahoogro ups.com
Date: Sunday, May 9, 2010, 10:37 AM


 





I've got Mikunis. I did this years ago on my 86-1100 and it never died even all the way in and I don't think it did much all the way out either but I'm gonna play with it. I forget, how do you turn the idele up on MIkunis? I had put them on my 86 when I removed my KJS single carb. Thanks, Mike

--- On Sun, 5/9/10, Bill's Personal <bill.stigall@ sbcglobal. net> wrote:Bill,





The base setting is 2.5 turns out from a soft seat. Every bike is different, so you have to adjust each carb until you get the best idle. In is leaner; out is richer...... .... As for the procedure; it is a good general procedure with the exception of adjusting the idle speed and the jet size..... On the Virago you need to consider the sync of the carbs if you try and adjust the idle speed. Hitachi's are individually adjustable for idle speed, I am not sure about Mikuni's. If you adjust your idle up, you may have to re-sync your carbs. The turn the pilot screw all the way in, make sure you don't tighten it down tight or it will damage both the needle and the seat. On a single cylinder engine, it might die when you lean it out, but that isn't necessarily true on a twin, it should slow the idle and perhaps start hitting on one cylinder. A better read on if you are running to rich or too lean it the color of your spark plugs.
The offset screw driver is a good idea. Also a flexible screwdriver will work as well. The pilot screws are on top of the carb throat in the Mikuni carb, so you will have to raise the fuel tank or remove it and use a bottle with some fuel in it and a hose connected to the carbs. The latter is the easier way IMHO.
 
Bill

----- Original Message -----
From: William Hall
To: ViragoTech@yahoogro ups.com
Sent: Sunday, May 09, 2010 7:49 AM
Subject: [ViragoTech] pilot adjustment

 






Here is a link and the verbage for setting the pilot. Does this sound good for our bikes? Seems like I remember the factory setting was 2.5 turns. What do you think? I got my ais removed and everything capped and now there is only a slight backfire at idle. With the Mikunis it's a pain to get at the screws. Does anyone use a 90 degree screwdriver and if so where did you get it and how much and des it reach both screw. Thanks, Mike
 
This is my prefered method of finding the proper setting for the pilot screw (aka fuel screw). This method can also indicate if your pilot jet is too big or too small. Towards the bottom is an explination about the difference between fuel screws and air screws.

You'll need to be able to access the fuel screw while the engine is running. This can be quite difficult on many carbs. FCRs have aftermarket fuel screws that are longer which helps. On a stock 400EX carb (and many others) I use a 90 degree screwdriver. I bit the bullet and bought this one from MotionPro. It works well but I'm sure there are others available. If you're lucky, your fuel screw is easily reached with a normal screw driver.

http://www.azjetski .com/catalog/ images/03MotionP roPilotAdjustSM. gif

OK. On to the procedure!

1) Warm up the engine to full operating temp.

2) Turn up your idle a few hundred RPM using the throttle stop screw (basically you want a fast idle). This will make it easier to hear small changes in RPM. Watch for overheating- -pointing a big shop fan at your engine will help it from getting too hot during the fast idling. The whole procedure shouldn't take too long though.

Each time you change the screw setting 1/4 or 1/2 turn or so, wait about 5 seconds to let the idle speed normalize. It usually take the carb and engine a moment to react to the change.

3) Turn the fuel screw IN until the idle starts to drop and miss. The engine should die if you bottom out the screw. Your pilot jet is too big if it doesn't die when the screw is bottomed out--it should die before it gets that far in.

4) Then begin turning the fuel screw OUT. The idle should peak and become smooth. Keep going and look for the idle to begin to drop/miss again.

5) The goal is to find the setting that provides the highest and smoothest idle. If it's unclear exactly were that point is then set to the midpoint between step #3 and step #4. For example, if the idle starts to drop at 1 turn out and starts to drop at 2 1/2 turns out then 1 3/4 of a turn out should be the correct setting.

If the peak/smoothest RPM is reached somewhere between 1-3 turns then your pilot jet is correct (the 1-3 turns applies to most carb types). If you end up less than 1 turn out then your pilot jet is too big and you need a smaller one. If you end up more than three turns out or the fuel screw seems to make little difference as you continue turning it out than you need to go up (bigger) on your pilot jet.

To re-emphisize: If the idle never drops when you're turning the fuel screw in, you need a smaller pilot jet. If the idle never drops when you're turning the fuel screw out, you need a bigger pilot jet.

Typical fuel screw settings are in the 1 1/2 to 2 1/2 range.

6) Once you've got the fuel screw set, re-adjust your throttle stop screw (idle screw) to an appropriate idle speed.

And that's it! Your pilot circuit is now VERY close to ideal. From here you can experiment with how small adjustments affect low-end (i.e. small throttle openings) response and make adjustments for weather. The hardest part is usually gaining access to the screw while the engine is running. Also, you may really have to listen carefully to detect the rpm changes in the idle. 100 or 200 rpm differences can be tough to detect when the change happens over several seconds.http://www.exriders .com/archive/ topic/229923- 1.html




Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: pilot adjustment

bill.stigall
Mike,
You can take your time and keep tweaking it until it is perfect, (patience), or if its running good and getting good gas mileage, you can just go riding and leave it be until a problem appears and then deal with it. I go with the latter......... My '83 XV920 could probably be tweaked up a bit, but it runs good, gets good gas mileage, (40-45 city, 48-50 highway), so I just leave it alone and ride it. I am running a little rich, but on these bikes, rich is better than lean as fuel helps some in cooling the engine and particularly the rear cylinder.
The key, IMHO, is to keep up the regular maintenance. Follow the maintenance and service maintenance instructions in your manual. I change plugs once per season and change oil and filter every 1500 miles. I have been using Castrol GTX 20w50, but with the next change, I will switch to Mobil 1 15w50 Synthetic since it has better cooling properties. I also run a can of SeaFoam through the gas tank twice per season, (1/2 can with a full tank), to keep my carbs clean and functioning well.
So its up to you how far you want to go with tuning.

Good and Safe Riding,
Bill

  ----- Original Message -----
  From: William Hall
  To: [hidden email]
  Sent: Monday, May 10, 2010 5:07 AM
  Subject: Re: [ViragoTech] pilot adjustment


   
        Ahh yes patience, sometimes thats had to come by. But I will try. Thanks, Mike

        --- On Sun, 5/9/10, Bill's Personal <[hidden email]> wrote:


          From: Bill's Personal <[hidden email]>
          Subject: Re: [ViragoTech] pilot adjustment
          To: [hidden email]
          Date: Sunday, May 9, 2010, 9:30 PM


           
          
          As you are probably aware, the plug color should be tan or both cylinders. If they are black, you will need to lean that carb out a little. Try 1/4 turn at a time and then run it again. If the plug color is white, then you will need to turn the pilot screw out and try again. The color may be different on each cylinder. On Mikuni carbs, the pilot jet handles idle and low speed, however when the engine speed picks up, the pilot jet is wide open and works in combination with the main jet to get the mixture for higher engine speeds. Therefore minor adjustments in high speed mixture can be made with the pilot screw.
          Once you have both carbs running with the correct mixture, (plug color tan on both cylinders), you should be good to go. Have patience, this can take a little while to get them dialed in.

          Bill

            ----- Original Message -----
            From: William Hall
            To: ViragoTech@yahoogro ups.com
            Sent: Sunday, May 09, 2010 5:50 PM
            Subject: Re: [ViragoTech] pilot adjustment


             
                  Well I set them both at 3 and no more backfire. I cleaned the plugs so after a bit of ridin I'll check them again. nstead of raising the rear of the gas tank I raised the front and it gave as much clearance as possible with the frame and wires in the way.Thanks, Mike

                  --- On Sun, 5/9/10, William Hall <wmh1968@att. net> wrote:


                    From: William Hall <wmh1968@att. net>
                    Subject: Re: [ViragoTech] pilot adjustment
                    To: ViragoTech@yahoogro ups.com
                    Date: Sunday, May 9, 2010, 10:37 AM


                     
                          I've got Mikunis. I did this years ago on my 86-1100 and it never died even all the way in and I don't think it did much all the way out either but I'm gonna play with it. I forget, how do you turn the idele up on MIkunis? I had put them on my 86 when I removed my KJS single carb. Thanks, Mike

                          --- On Sun, 5/9/10, Bill's Personal <bill.stigall@ sbcglobal. net> wrote:Bill,
                            The base setting is 2.5 turns out from a soft seat. Every bike is different, so you have to adjust each carb until you get the best idle. In is leaner; out is richer...... .... As for the procedure; it is a good general procedure with the exception of adjusting the idle speed and the jet size..... On the Virago you need to consider the sync of the carbs if you try and adjust the idle speed. Hitachi's are individually adjustable for idle speed, I am not sure about Mikuni's. If you adjust your idle up, you may have to re-sync your carbs. The turn the pilot screw all the way in, make sure you don't tighten it down tight or it will damage both the needle and the seat. On a single cylinder engine, it might die when you lean it out, but that isn't necessarily true on a twin, it should slow the idle and perhaps start hitting on one cylinder. A better read on if you are running to rich or too lean it the color of your spark plugs.
                            The offset screw driver is a good idea. Also a flexible screwdriver will work as well. The pilot screws are on top of the carb throat in the Mikuni carb, so you will have to raise the fuel tank or remove it and use a bottle with some fuel in it and a hose connected to the carbs. The latter is the easier way IMHO.

                            Bill
                              ----- Original Message -----
                              From: William Hall
                              To: ViragoTech@yahoogro ups.com
                              Sent: Sunday, May 09, 2010 7:49 AM
                              Subject: [ViragoTech] pilot adjustment


                               
                                Here is a link and the verbage for setting the pilot. Does this sound good for our bikes? Seems like I remember the factory setting was 2.5 turns. What do you think? I got my ais removed and everything capped and now there is only a slight backfire at idle. With the Mikunis it's a pain to get at the screws. Does anyone use a 90 degree screwdriver and if so where did you get it and how much and des it reach both screw. Thanks, Mike

                                This is my prefered method of finding the proper setting for the pilot screw (aka fuel screw). This method can also indicate if your pilot jet is too big or too small. Towards the bottom is an explination about the difference between fuel screws and air screws.

                                You'll need to be able to access the fuel screw while the engine is running. This can be quite difficult on many carbs. FCRs have aftermarket fuel screws that are longer which helps. On a stock 400EX carb (and many others) I use a 90 degree screwdriver. I bit the bullet and bought this one from MotionPro. It works well but I'm sure there are others available. If you're lucky, your fuel screw is easily reached with a normal screw driver.

                                http://www.azjetski .com/catalog/ images/03MotionP roPilotAdjustSM. gif

                                OK. On to the procedure!

                                1) Warm up the engine to full operating temp.

                                2) Turn up your idle a few hundred RPM using the throttle stop screw (basically you want a fast idle). This will make it easier to hear small changes in RPM. Watch for overheating- -pointing a big shop fan at your engine will help it from getting too hot during the fast idling. The whole procedure shouldn't take too long though.

                                Each time you change the screw setting 1/4 or 1/2 turn or so, wait about 5 seconds to let the idle speed normalize. It usually take the carb and engine a moment to react to the change.

                                3) Turn the fuel screw IN until the idle starts to drop and miss. The engine should die if you bottom out the screw. Your pilot jet is too big if it doesn't die when the screw is bottomed out--it should die before it gets that far in.

                                4) Then begin turning the fuel screw OUT. The idle should peak and become smooth. Keep going and look for the idle to begin to drop/miss again.

                                5) The goal is to find the setting that provides the highest and smoothest idle. If it's unclear exactly were that point is then set to the midpoint between step #3 and step #4. For example, if the idle starts to drop at 1 turn out and starts to drop at 2 1/2 turns out then 1 3/4 of a turn out should be the correct setting.

                                If the peak/smoothest RPM is reached somewhere between 1-3 turns then your pilot jet is correct (the 1-3 turns applies to most carb types). If you end up less than 1 turn out then your pilot jet is too big and you need a smaller one. If you end up more than three turns out or the fuel screw seems to make little difference as you continue turning it out than you need to go up (bigger) on your pilot jet.

                                To re-emphisize: If the idle never drops when you're turning the fuel screw in, you need a smaller pilot jet. If the idle never drops when you're turning the fuel screw out, you need a bigger pilot jet.

                                Typical fuel screw settings are in the 1 1/2 to 2 1/2 range.

                                6) Once you've got the fuel screw set, re-adjust your throttle stop screw (idle screw) to an appropriate idle speed.

                                And that's it! Your pilot circuit is now VERY close to ideal. From here you can experiment with how small adjustments affect low-end (i.e. small throttle openings) response and make adjustments for weather. The hardest part is usually gaining access to the screw while the engine is running. Also, you may really have to listen carefully to detect the rpm changes in the idle. 100 or 200 rpm differences can be tough to detect when the change happens over several seconds.http://www.exriders .com/archive/ topic/229923- 1.html
                         
                 
       


 
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: pilot adjustment

William Hall
I've used seafoam for years in everything. I do try to take care of my bikes. When I sold my 86 he bought it sight unseen and paid to have it shipped and couldn't believe how nice it was. Thanks, Mike

--- On Mon, 5/10/10, Bill's Personal <[hidden email]> wrote:


From: Bill's Personal <[hidden email]>
Subject: Re: [ViragoTech] pilot adjustment
To: [hidden email]
Date: Monday, May 10, 2010, 10:06 AM


 




Mike,
You can take your time and keep tweaking it until it is perfect, (patience), or if its running good and getting good gas mileage, you can just go riding and leave it be until a problem appears and then deal with it. I go with the latter...... ... My '83 XV920 could probably be tweaked up a bit, but it runs good, gets good gas mileage, (40-45 city, 48-50 highway), so I just leave it alone and ride it. I am running a little rich, but on these bikes, rich is better than lean as fuel helps some in cooling the engine and particularly the rear cylinder.
The key, IMHO, is to keep up the regular maintenance. Follow the maintenance and service maintenance instructions in your manual. I change plugs once per season and change oil and filter every 1500 miles. I have been using Castrol GTX 20w50, but with the next change, I will switch to Mobil 1 15w50 Synthetic since it has better cooling properties. I also run a can of SeaFoam through the gas tank twice per season, (1/2 can with a full tank), to keep my carbs clean and functioning well.
So its up to you how far you want to go with tuning.
 
Good and Safe Riding,
Bill
 

----- Original Message -----
From: William Hall
To: ViragoTech@yahoogro ups.com
Sent: Monday, May 10, 2010 5:07 AM
Subject: Re: [ViragoTech] pilot adjustment

 





Ahh yes patience, sometimes thats had to come by. But I will try. Thanks, Mike

--- On Sun, 5/9/10, Bill's Personal <bill.stigall@ sbcglobal. net> wrote:


From: Bill's Personal <bill.stigall@ sbcglobal. net>
Subject: Re: [ViragoTech] pilot adjustment
To: ViragoTech@yahoogro ups.com
Date: Sunday, May 9, 2010, 9:30 PM


 


As you are probably aware, the plug color should be tan or both cylinders. If they are black, you will need to lean that carb out a little. Try 1/4 turn at a time and then run it again. If the plug color is white, then you will need to turn the pilot screw out and try again. The color may be different on each cylinder. On Mikuni carbs, the pilot jet handles idle and low speed, however when the engine speed picks up, the pilot jet is wide open and works in combination with the main jet to get the mixture for higher engine speeds. Therefore minor adjustments in high speed mixture can be made with the pilot screw.
Once you have both carbs running with the correct mixture, (plug color tan on both cylinders), you should be good to go. Have patience, this can take a little while to get them dialed in.
 
Bill
 

----- Original Message -----
From: William Hall
To: ViragoTech@yahoogro ups.com
Sent: Sunday, May 09, 2010 5:50 PM
Subject: Re: [ViragoTech] pilot adjustment

 





Well I set them both at 3 and no more backfire. I cleaned the plugs so after a bit of ridin I'll check them again. nstead of raising the rear of the gas tank I raised the front and it gave as much clearance as possible with the frame and wires in the way.Thanks, Mike

--- On Sun, 5/9/10, William Hall <wmh1968@att. net> wrote:


From: William Hall <wmh1968@att. net>
Subject: Re: [ViragoTech] pilot adjustment
To: ViragoTech@yahoogro ups.com
Date: Sunday, May 9, 2010, 10:37 AM


 





I've got Mikunis. I did this years ago on my 86-1100 and it never died even all the way in and I don't think it did much all the way out either but I'm gonna play with it. I forget, how do you turn the idele up on MIkunis? I had put them on my 86 when I removed my KJS single carb. Thanks, Mike

--- On Sun, 5/9/10, Bill's Personal <bill.stigall@ sbcglobal. net> wrote:Bill,





The base setting is 2.5 turns out from a soft seat. Every bike is different, so you have to adjust each carb until you get the best idle. In is leaner; out is richer...... .... As for the procedure; it is a good general procedure with the exception of adjusting the idle speed and the jet size..... On the Virago you need to consider the sync of the carbs if you try and adjust the idle speed. Hitachi's are individually adjustable for idle speed, I am not sure about Mikuni's. If you adjust your idle up, you may have to re-sync your carbs. The turn the pilot screw all the way in, make sure you don't tighten it down tight or it will damage both the needle and the seat. On a single cylinder engine, it might die when you lean it out, but that isn't necessarily true on a twin, it should slow the idle and perhaps start hitting on one cylinder. A better read on if you are running to rich or too lean it the color of your spark plugs.
The offset screw driver is a good idea. Also a flexible screwdriver will work as well. The pilot screws are on top of the carb throat in the Mikuni carb, so you will have to raise the fuel tank or remove it and use a bottle with some fuel in it and a hose connected to the carbs. The latter is the easier way IMHO.
 
Bill

----- Original Message -----
From: William Hall
To: ViragoTech@yahoogro ups.com
Sent: Sunday, May 09, 2010 7:49 AM
Subject: [ViragoTech] pilot adjustment

 






Here is a link and the verbage for setting the pilot. Does this sound good for our bikes? Seems like I remember the factory setting was 2.5 turns. What do you think? I got my ais removed and everything capped and now there is only a slight backfire at idle. With the Mikunis it's a pain to get at the screws. Does anyone use a 90 degree screwdriver and if so where did you get it and how much and des it reach both screw. Thanks, Mike
 
This is my prefered method of finding the proper setting for the pilot screw (aka fuel screw). This method can also indicate if your pilot jet is too big or too small. Towards the bottom is an explination about the difference between fuel screws and air screws.

You'll need to be able to access the fuel screw while the engine is running. This can be quite difficult on many carbs. FCRs have aftermarket fuel screws that are longer which helps. On a stock 400EX carb (and many others) I use a 90 degree screwdriver. I bit the bullet and bought this one from MotionPro. It works well but I'm sure there are others available. If you're lucky, your fuel screw is easily reached with a normal screw driver.

http://www.azjetski .com/catalog/ images/03MotionP roPilotAdjustSM. gif

OK. On to the procedure!

1) Warm up the engine to full operating temp.

2) Turn up your idle a few hundred RPM using the throttle stop screw (basically you want a fast idle). This will make it easier to hear small changes in RPM. Watch for overheating- -pointing a big shop fan at your engine will help it from getting too hot during the fast idling. The whole procedure shouldn't take too long though.

Each time you change the screw setting 1/4 or 1/2 turn or so, wait about 5 seconds to let the idle speed normalize. It usually take the carb and engine a moment to react to the change.

3) Turn the fuel screw IN until the idle starts to drop and miss. The engine should die if you bottom out the screw. Your pilot jet is too big if it doesn't die when the screw is bottomed out--it should die before it gets that far in.

4) Then begin turning the fuel screw OUT. The idle should peak and become smooth. Keep going and look for the idle to begin to drop/miss again.

5) The goal is to find the setting that provides the highest and smoothest idle. If it's unclear exactly were that point is then set to the midpoint between step #3 and step #4. For example, if the idle starts to drop at 1 turn out and starts to drop at 2 1/2 turns out then 1 3/4 of a turn out should be the correct setting.

If the peak/smoothest RPM is reached somewhere between 1-3 turns then your pilot jet is correct (the 1-3 turns applies to most carb types). If you end up less than 1 turn out then your pilot jet is too big and you need a smaller one. If you end up more than three turns out or the fuel screw seems to make little difference as you continue turning it out than you need to go up (bigger) on your pilot jet.

To re-emphisize: If the idle never drops when you're turning the fuel screw in, you need a smaller pilot jet. If the idle never drops when you're turning the fuel screw out, you need a bigger pilot jet.

Typical fuel screw settings are in the 1 1/2 to 2 1/2 range.

6) Once you've got the fuel screw set, re-adjust your throttle stop screw (idle screw) to an appropriate idle speed.

And that's it! Your pilot circuit is now VERY close to ideal. From here you can experiment with how small adjustments affect low-end (i.e. small throttle openings) response and make adjustments for weather. The hardest part is usually gaining access to the screw while the engine is running. Also, you may really have to listen carefully to detect the rpm changes in the idle. 100 or 200 rpm differences can be tough to detect when the change happens over several seconds.http://www.exriders .com/archive/ topic/229923- 1.html




Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: pilot adjustment

bill.stigall
Where are you located?
Bill
  ----- Original Message -----
  From: William Hall
  To: [hidden email]
  Sent: Monday, May 10, 2010 6:24 PM
  Subject: Re: [ViragoTech] pilot adjustment


   
        I've used seafoam for years in everything. I do try to take care of my bikes. When I sold my 86 he bought it sight unseen and paid to have it shipped and couldn't believe how nice it was. Thanks, Mike

        --- On Mon, 5/10/10, Bill's Personal <[hidden email]> wrote:


          From: Bill's Personal <[hidden email]>
          Subject: Re: [ViragoTech] pilot adjustment
          To: [hidden email]
          Date: Monday, May 10, 2010, 10:06 AM


           
          
          Mike,
          You can take your time and keep tweaking it until it is perfect, (patience), or if its running good and getting good gas mileage, you can just go riding and leave it be until a problem appears and then deal with it. I go with the latter...... ... My '83 XV920 could probably be tweaked up a bit, but it runs good, gets good gas mileage, (40-45 city, 48-50 highway), so I just leave it alone and ride it. I am running a little rich, but on these bikes, rich is better than lean as fuel helps some in cooling the engine and particularly the rear cylinder.
          The key, IMHO, is to keep up the regular maintenance. Follow the maintenance and service maintenance instructions in your manual. I change plugs once per season and change oil and filter every 1500 miles. I have been using Castrol GTX 20w50, but with the next change, I will switch to Mobil 1 15w50 Synthetic since it has better cooling properties. I also run a can of SeaFoam through the gas tank twice per season, (1/2 can with a full tank), to keep my carbs clean and functioning well.
          So its up to you how far you want to go with tuning.

          Good and Safe Riding,
          Bill

            ----- Original Message -----
            From: William Hall
            To: ViragoTech@yahoogro ups.com
            Sent: Monday, May 10, 2010 5:07 AM
            Subject: Re: [ViragoTech] pilot adjustment


             
                  Ahh yes patience, sometimes thats had to come by. But I will try. Thanks, Mike

                  --- On Sun, 5/9/10, Bill's Personal <bill.stigall@ sbcglobal. net> wrote:


                    From: Bill's Personal <bill.stigall@ sbcglobal. net>
                    Subject: Re: [ViragoTech] pilot adjustment
                    To: ViragoTech@yahoogro ups.com
                    Date: Sunday, May 9, 2010, 9:30 PM


                     
                    
                    As you are probably aware, the plug color should be tan or both cylinders. If they are black, you will need to lean that carb out a little. Try 1/4 turn at a time and then run it again. If the plug color is white, then you will need to turn the pilot screw out and try again. The color may be different on each cylinder. On Mikuni carbs, the pilot jet handles idle and low speed, however when the engine speed picks up, the pilot jet is wide open and works in combination with the main jet to get the mixture for higher engine speeds. Therefore minor adjustments in high speed mixture can be made with the pilot screw.
                    Once you have both carbs running with the correct mixture, (plug color tan on both cylinders), you should be good to go. Have patience, this can take a little while to get them dialed in.

                    Bill

                      ----- Original Message -----
                      From: William Hall
                      To: ViragoTech@yahoogro ups.com
                      Sent: Sunday, May 09, 2010 5:50 PM
                      Subject: Re: [ViragoTech] pilot adjustment


                       
                            Well I set them both at 3 and no more backfire. I cleaned the plugs so after a bit of ridin I'll check them again. nstead of raising the rear of the gas tank I raised the front and it gave as much clearance as possible with the frame and wires in the way.Thanks, Mike

                            --- On Sun, 5/9/10, William Hall <wmh1968@att. net> wrote:


                              From: William Hall <wmh1968@att. net>
                              Subject: Re: [ViragoTech] pilot adjustment
                              To: ViragoTech@yahoogro ups.com
                              Date: Sunday, May 9, 2010, 10:37 AM


                               
                                I've got Mikunis. I did this years ago on my 86-1100 and it never died even all the way in and I don't think it did much all the way out either but I'm gonna play with it. I forget, how do you turn the idele up on MIkunis? I had put them on my 86 when I removed my KJS single carb. Thanks, Mike

                                --- On Sun, 5/9/10, Bill's Personal <bill.stigall@ sbcglobal. net> wrote:Bill,
                                The base setting is 2.5 turns out from a soft seat. Every bike is different, so you have to adjust each carb until you get the best idle. In is leaner; out is richer...... .... As for the procedure; it is a good general procedure with the exception of adjusting the idle speed and the jet size..... On the Virago you need to consider the sync of the carbs if you try and adjust the idle speed. Hitachi's are individually adjustable for idle speed, I am not sure about Mikuni's. If you adjust your idle up, you may have to re-sync your carbs. The turn the pilot screw all the way in, make sure you don't tighten it down tight or it will damage both the needle and the seat. On a single cylinder engine, it might die when you lean it out, but that isn't necessarily true on a twin, it should slow the idle and perhaps start hitting on one cylinder. A better read on if you are running to rich or too lean it the color of your spark plugs.
                                The offset screw driver is a good idea. Also a flexible screwdriver will work as well. The pilot screws are on top of the carb throat in the Mikuni carb, so you will have to raise the fuel tank or remove it and use a bottle with some fuel in it and a hose connected to the carbs. The latter is the easier way IMHO.

                                Bill
                                ----- Original Message -----
                                From: William Hall
                                To: ViragoTech@yahoogro ups.com
                                Sent: Sunday, May 09, 2010 7:49 AM
                                Subject: [ViragoTech] pilot adjustment


                                 
                                Here is a link and the verbage for setting the pilot. Does this sound good for our bikes? Seems like I remember the factory setting was 2.5 turns. What do you think? I got my ais removed and everything capped and now there is only a slight backfire at idle. With the Mikunis it's a pain to get at the screws. Does anyone use a 90 degree screwdriver and if so where did you get it and how much and des it reach both screw. Thanks, Mike

                                This is my prefered method of finding the proper setting for the pilot screw (aka fuel screw). This method can also indicate if your pilot jet is too big or too small. Towards the bottom is an explination about the difference between fuel screws and air screws.

                                You'll need to be able to access the fuel screw while the engine is running. This can be quite difficult on many carbs. FCRs have aftermarket fuel screws that are longer which helps. On a stock 400EX carb (and many others) I use a 90 degree screwdriver. I bit the bullet and bought this one from MotionPro. It works well but I'm sure there are others available. If you're lucky, your fuel screw is easily reached with a normal screw driver.

                                http://www.azjetski .com/catalog/ images/03MotionP roPilotAdjustSM. gif

                                OK. On to the procedure!

                                1) Warm up the engine to full operating temp.

                                2) Turn up your idle a few hundred RPM using the throttle stop screw (basically you want a fast idle). This will make it easier to hear small changes in RPM. Watch for overheating- -pointing a big shop fan at your engine will help it from getting too hot during the fast idling. The whole procedure shouldn't take too long though.

                                Each time you change the screw setting 1/4 or 1/2 turn or so, wait about 5 seconds to let the idle speed normalize. It usually take the carb and engine a moment to react to the change.

                                3) Turn the fuel screw IN until the idle starts to drop and miss. The engine should die if you bottom out the screw. Your pilot jet is too big if it doesn't die when the screw is bottomed out--it should die before it gets that far in.

                                4) Then begin turning the fuel screw OUT. The idle should peak and become smooth. Keep going and look for the idle to begin to drop/miss again.

                                5) The goal is to find the setting that provides the highest and smoothest idle. If it's unclear exactly were that point is then set to the midpoint between step #3 and step #4. For example, if the idle starts to drop at 1 turn out and starts to drop at 2 1/2 turns out then 1 3/4 of a turn out should be the correct setting.

                                If the peak/smoothest RPM is reached somewhere between 1-3 turns then your pilot jet is correct (the 1-3 turns applies to most carb types). If you end up less than 1 turn out then your pilot jet is too big and you need a smaller one. If you end up more than three turns out or the fuel screw seems to make little difference as you continue turning it out than you need to go up (bigger) on your pilot jet.

                                To re-emphisize: If the idle never drops when you're turning the fuel screw in, you need a smaller pilot jet. If the idle never drops when you're turning the fuel screw out, you need a bigger pilot jet.

                                Typical fuel screw settings are in the 1 1/2 to 2 1/2 range.

                                6) Once you've got the fuel screw set, re-adjust your throttle stop screw (idle screw) to an appropriate idle speed.

                                And that's it! Your pilot circuit is now VERY close to ideal. From here you can experiment with how small adjustments affect low-end (i.e. small throttle openings) response and make adjustments for weather. The hardest part is usually gaining access to the screw while the engine is running. Also, you may really have to listen carefully to detect the rpm changes in the idle. 100 or 200 rpm differences can be tough to detect when the change happens over several seconds.http://www.exriders .com/archive/ topic/229923- 1.html
                                 
                           
                 
       


 
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: pilot adjustment

William Hall
Flossmoor, Il, a South suburb of Chicago. Mike

--- On Mon, 5/10/10, Bill Stigall <[hidden email]> wrote:


From: Bill Stigall <[hidden email]>
Subject: Re: [ViragoTech] pilot adjustment
To: [hidden email]
Date: Monday, May 10, 2010, 8:41 PM


 




Where are you located?
Bill

----- Original Message -----
From: William Hall
To: ViragoTech@yahoogro ups.com
Sent: Monday, May 10, 2010 6:24 PM
Subject: Re: [ViragoTech] pilot adjustment

 





I've used seafoam for years in everything. I do try to take care of my bikes. When I sold my 86 he bought it sight unseen and paid to have it shipped and couldn't believe how nice it was. Thanks, Mike

--- On Mon, 5/10/10, Bill's Personal <bill.stigall@ sbcglobal. net> wrote:


From: Bill's Personal <bill.stigall@ sbcglobal. net>
Subject: Re: [ViragoTech] pilot adjustment
To: ViragoTech@yahoogro ups.com
Date: Monday, May 10, 2010, 10:06 AM


 


Mike,
You can take your time and keep tweaking it until it is perfect, (patience), or if its running good and getting good gas mileage, you can just go riding and leave it be until a problem appears and then deal with it. I go with the latter...... ... My '83 XV920 could probably be tweaked up a bit, but it runs good, gets good gas mileage, (40-45 city, 48-50 highway), so I just leave it alone and ride it. I am running a little rich, but on these bikes, rich is better than lean as fuel helps some in cooling the engine and particularly the rear cylinder.
The key, IMHO, is to keep up the regular maintenance. Follow the maintenance and service maintenance instructions in your manual. I change plugs once per season and change oil and filter every 1500 miles. I have been using Castrol GTX 20w50, but with the next change, I will switch to Mobil 1 15w50 Synthetic since it has better cooling properties. I also run a can of SeaFoam through the gas tank twice per season, (1/2 can with a full tank), to keep my carbs clean and functioning well.
So its up to you how far you want to go with tuning.
 
Good and Safe Riding,
Bill
 

----- Original Message -----
From: William Hall
To: ViragoTech@yahoogro ups.com
Sent: Monday, May 10, 2010 5:07 AM
Subject: Re: [ViragoTech] pilot adjustment

 





Ahh yes patience, sometimes thats had to come by. But I will try. Thanks, Mike

--- On Sun, 5/9/10, Bill's Personal <bill.stigall@ sbcglobal. net> wrote:


From: Bill's Personal <bill.stigall@ sbcglobal. net>
Subject: Re: [ViragoTech] pilot adjustment
To: ViragoTech@yahoogro ups.com
Date: Sunday, May 9, 2010, 9:30 PM


 


As you are probably aware, the plug color should be tan or both cylinders. If they are black, you will need to lean that carb out a little. Try 1/4 turn at a time and then run it again. If the plug color is white, then you will need to turn the pilot screw out and try again. The color may be different on each cylinder. On Mikuni carbs, the pilot jet handles idle and low speed, however when the engine speed picks up, the pilot jet is wide open and works in combination with the main jet to get the mixture for higher engine speeds. Therefore minor adjustments in high speed mixture can be made with the pilot screw.
Once you have both carbs running with the correct mixture, (plug color tan on both cylinders), you should be good to go. Have patience, this can take a little while to get them dialed in.
 
Bill
 

----- Original Message -----
From: William Hall
To: ViragoTech@yahoogro ups.com
Sent: Sunday, May 09, 2010 5:50 PM
Subject: Re: [ViragoTech] pilot adjustment

 





Well I set them both at 3 and no more backfire. I cleaned the plugs so after a bit of ridin I'll check them again. nstead of raising the rear of the gas tank I raised the front and it gave as much clearance as possible with the frame and wires in the way.Thanks, Mike

--- On Sun, 5/9/10, William Hall <wmh1968@att. net> wrote:


From: William Hall <wmh1968@att. net>
Subject: Re: [ViragoTech] pilot adjustment
To: ViragoTech@yahoogro ups.com
Date: Sunday, May 9, 2010, 10:37 AM


 





I've got Mikunis. I did this years ago on my 86-1100 and it never died even all the way in and I don't think it did much all the way out either but I'm gonna play with it. I forget, how do you turn the idele up on MIkunis? I had put them on my 86 when I removed my KJS single carb. Thanks, Mike

--- On Sun, 5/9/10, Bill's Personal <bill.stigall@ sbcglobal. net> wrote:Bill,





The base setting is 2.5 turns out from a soft seat. Every bike is different, so you have to adjust each carb until you get the best idle. In is leaner; out is richer...... .... As for the procedure; it is a good general procedure with the exception of adjusting the idle speed and the jet size..... On the Virago you need to consider the sync of the carbs if you try and adjust the idle speed. Hitachi's are individually adjustable for idle speed, I am not sure about Mikuni's. If you adjust your idle up, you may have to re-sync your carbs. The turn the pilot screw all the way in, make sure you don't tighten it down tight or it will damage both the needle and the seat. On a single cylinder engine, it might die when you lean it out, but that isn't necessarily true on a twin, it should slow the idle and perhaps start hitting on one cylinder. A better read on if you are running to rich or too lean it the color of your spark plugs.
The offset screw driver is a good idea. Also a flexible screwdriver will work as well. The pilot screws are on top of the carb throat in the Mikuni carb, so you will have to raise the fuel tank or remove it and use a bottle with some fuel in it and a hose connected to the carbs. The latter is the easier way IMHO.
 
Bill

----- Original Message -----
From: William Hall
To: ViragoTech@yahoogro ups.com
Sent: Sunday, May 09, 2010 7:49 AM
Subject: [ViragoTech] pilot adjustment

 






Here is a link and the verbage for setting the pilot. Does this sound good for our bikes? Seems like I remember the factory setting was 2.5 turns. What do you think? I got my ais removed and everything capped and now there is only a slight backfire at idle. With the Mikunis it's a pain to get at the screws. Does anyone use a 90 degree screwdriver and if so where did you get it and how much and des it reach both screw. Thanks, Mike
 
This is my prefered method of finding the proper setting for the pilot screw (aka fuel screw). This method can also indicate if your pilot jet is too big or too small. Towards the bottom is an explination about the difference between fuel screws and air screws.

You'll need to be able to access the fuel screw while the engine is running. This can be quite difficult on many carbs. FCRs have aftermarket fuel screws that are longer which helps. On a stock 400EX carb (and many others) I use a 90 degree screwdriver. I bit the bullet and bought this one from MotionPro. It works well but I'm sure there are others available. If you're lucky, your fuel screw is easily reached with a normal screw driver.

http://www.azjetski .com/catalog/ images/03MotionP roPilotAdjustSM. gif

OK. On to the procedure!

1) Warm up the engine to full operating temp.

2) Turn up your idle a few hundred RPM using the throttle stop screw (basically you want a fast idle). This will make it easier to hear small changes in RPM. Watch for overheating- -pointing a big shop fan at your engine will help it from getting too hot during the fast idling. The whole procedure shouldn't take too long though.

Each time you change the screw setting 1/4 or 1/2 turn or so, wait about 5 seconds to let the idle speed normalize. It usually take the carb and engine a moment to react to the change.

3) Turn the fuel screw IN until the idle starts to drop and miss. The engine should die if you bottom out the screw. Your pilot jet is too big if it doesn't die when the screw is bottomed out--it should die before it gets that far in.

4) Then begin turning the fuel screw OUT. The idle should peak and become smooth. Keep going and look for the idle to begin to drop/miss again.

5) The goal is to find the setting that provides the highest and smoothest idle. If it's unclear exactly were that point is then set to the midpoint between step #3 and step #4. For example, if the idle starts to drop at 1 turn out and starts to drop at 2 1/2 turns out then 1 3/4 of a turn out should be the correct setting.

If the peak/smoothest RPM is reached somewhere between 1-3 turns then your pilot jet is correct (the 1-3 turns applies to most carb types). If you end up less than 1 turn out then your pilot jet is too big and you need a smaller one. If you end up more than three turns out or the fuel screw seems to make little difference as you continue turning it out than you need to go up (bigger) on your pilot jet.

To re-emphisize: If the idle never drops when you're turning the fuel screw in, you need a smaller pilot jet. If the idle never drops when you're turning the fuel screw out, you need a bigger pilot jet.

Typical fuel screw settings are in the 1 1/2 to 2 1/2 range.

6) Once you've got the fuel screw set, re-adjust your throttle stop screw (idle screw) to an appropriate idle speed.

And that's it! Your pilot circuit is now VERY close to ideal. From here you can experiment with how small adjustments affect low-end (i.e. small throttle openings) response and make adjustments for weather. The hardest part is usually gaining access to the screw while the engine is running. Also, you may really have to listen carefully to detect the rpm changes in the idle. 100 or 200 rpm differences can be tough to detect when the change happens over several seconds.http://www.exriders .com/archive/ topic/229923- 1.html




Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: pilot adjustment

bill.stigall
Too cold for me!  I am in the Sierra Foothills of Northern California near Nevada City.

Bill
  ----- Original Message -----
  From: William Hall
  To: [hidden email]
  Sent: Monday, May 10, 2010 6:57 PM
  Subject: Re: [ViragoTech] pilot adjustment


   
        Flossmoor, Il, a South suburb of Chicago. Mike

        --- On Mon, 5/10/10, Bill Stigall <[hidden email]> wrote:


          From: Bill Stigall <[hidden email]>
          Subject: Re: [ViragoTech] pilot adjustment
          To: [hidden email]
          Date: Monday, May 10, 2010, 8:41 PM


           
          
          Where are you located?
          Bill
            ----- Original Message -----
            From: William Hall
            To: ViragoTech@yahoogro ups.com
            Sent: Monday, May 10, 2010 6:24 PM
            Subject: Re: [ViragoTech] pilot adjustment


             
                  I've used seafoam for years in everything. I do try to take care of my bikes. When I sold my 86 he bought it sight unseen and paid to have it shipped and couldn't believe how nice it was. Thanks, Mike

                  --- On Mon, 5/10/10, Bill's Personal <bill.stigall@ sbcglobal. net> wrote:


                    From: Bill's Personal <bill.stigall@ sbcglobal. net>
                    Subject: Re: [ViragoTech] pilot adjustment
                    To: ViragoTech@yahoogro ups.com
                    Date: Monday, May 10, 2010, 10:06 AM


                     
                    
                    Mike,
                    You can take your time and keep tweaking it until it is perfect, (patience), or if its running good and getting good gas mileage, you can just go riding and leave it be until a problem appears and then deal with it. I go with the latter...... ... My '83 XV920 could probably be tweaked up a bit, but it runs good, gets good gas mileage, (40-45 city, 48-50 highway), so I just leave it alone and ride it. I am running a little rich, but on these bikes, rich is better than lean as fuel helps some in cooling the engine and particularly the rear cylinder.
                    The key, IMHO, is to keep up the regular maintenance. Follow the maintenance and service maintenance instructions in your manual. I change plugs once per season and change oil and filter every 1500 miles. I have been using Castrol GTX 20w50, but with the next change, I will switch to Mobil 1 15w50 Synthetic since it has better cooling properties. I also run a can of SeaFoam through the gas tank twice per season, (1/2 can with a full tank), to keep my carbs clean and functioning well.
                    So its up to you how far you want to go with tuning.

                    Good and Safe Riding,
                    Bill

                      ----- Original Message -----
                      From: William Hall
                      To: ViragoTech@yahoogro ups.com
                      Sent: Monday, May 10, 2010 5:07 AM
                      Subject: Re: [ViragoTech] pilot adjustment


                       
                            Ahh yes patience, sometimes thats had to come by. But I will try. Thanks, Mike

                            --- On Sun, 5/9/10, Bill's Personal <bill.stigall@ sbcglobal. net> wrote:


                              From: Bill's Personal <bill.stigall@ sbcglobal. net>
                              Subject: Re: [ViragoTech] pilot adjustment
                              To: ViragoTech@yahoogro ups.com
                              Date: Sunday, May 9, 2010, 9:30 PM


                               
                              
                              As you are probably aware, the plug color should be tan or both cylinders. If they are black, you will need to lean that carb out a little. Try 1/4 turn at a time and then run it again. If the plug color is white, then you will need to turn the pilot screw out and try again. The color may be different on each cylinder. On Mikuni carbs, the pilot jet handles idle and low speed, however when the engine speed picks up, the pilot jet is wide open and works in combination with the main jet to get the mixture for higher engine speeds. Therefore minor adjustments in high speed mixture can be made with the pilot screw.
                              Once you have both carbs running with the correct mixture, (plug color tan on both cylinders), you should be good to go. Have patience, this can take a little while to get them dialed in.

                              Bill

                                ----- Original Message -----
                                From: William Hall
                                To: ViragoTech@yahoogro ups.com
                                Sent: Sunday, May 09, 2010 5:50 PM
                                Subject: Re: [ViragoTech] pilot adjustment


                                 
                                Well I set them both at 3 and no more backfire. I cleaned the plugs so after a bit of ridin I'll check them again. nstead of raising the rear of the gas tank I raised the front and it gave as much clearance as possible with the frame and wires in the way.Thanks, Mike

                                --- On Sun, 5/9/10, William Hall <wmh1968@att. net> wrote:


                                From: William Hall <wmh1968@att. net>
                                Subject: Re: [ViragoTech] pilot adjustment
                                To: ViragoTech@yahoogro ups.com
                                Date: Sunday, May 9, 2010, 10:37 AM


                                 
                                I've got Mikunis. I did this years ago on my 86-1100 and it never died even all the way in and I don't think it did much all the way out either but I'm gonna play with it. I forget, how do you turn the idele up on MIkunis? I had put them on my 86 when I removed my KJS single carb. Thanks, Mike

                                --- On Sun, 5/9/10, Bill's Personal <bill.stigall@ sbcglobal. net> wrote:Bill,
                                The base setting is 2.5 turns out from a soft seat. Every bike is different, so you have to adjust each carb until you get the best idle. In is leaner; out is richer...... .... As for the procedure; it is a good general procedure with the exception of adjusting the idle speed and the jet size..... On the Virago you need to consider the sync of the carbs if you try and adjust the idle speed. Hitachi's are individually adjustable for idle speed, I am not sure about Mikuni's. If you adjust your idle up, you may have to re-sync your carbs. The turn the pilot screw all the way in, make sure you don't tighten it down tight or it will damage both the needle and the seat. On a single cylinder engine, it might die when you lean it out, but that isn't necessarily true on a twin, it should slow the idle and perhaps start hitting on one cylinder. A better read on if you are running to rich or too lean it the color of your spark plugs.
                                The offset screw driver is a good idea. Also a flexible screwdriver will work as well. The pilot screws are on top of the carb throat in the Mikuni carb, so you will have to raise the fuel tank or remove it and use a bottle with some fuel in it and a hose connected to the carbs. The latter is the easier way IMHO.

                                Bill
                                ----- Original Message -----
                                From: William Hall
                                To: ViragoTech@yahoogro ups.com
                                Sent: Sunday, May 09, 2010 7:49 AM
                                Subject: [ViragoTech] pilot adjustment


                                 
                                Here is a link and the verbage for setting the pilot. Does this sound good for our bikes? Seems like I remember the factory setting was 2.5 turns. What do you think? I got my ais removed and everything capped and now there is only a slight backfire at idle. With the Mikunis it's a pain to get at the screws. Does anyone use a 90 degree screwdriver and if so where did you get it and how much and des it reach both screw. Thanks, Mike

                                This is my prefered method of finding the proper setting for the pilot screw (aka fuel screw). This method can also indicate if your pilot jet is too big or too small. Towards the bottom is an explination about the difference between fuel screws and air screws.

                                You'll need to be able to access the fuel screw while the engine is running. This can be quite difficult on many carbs. FCRs have aftermarket fuel screws that are longer which helps. On a stock 400EX carb (and many others) I use a 90 degree screwdriver. I bit the bullet and bought this one from MotionPro. It works well but I'm sure there are others available. If you're lucky, your fuel screw is easily reached with a normal screw driver.

                                http://www.azjetski .com/catalog/ images/03MotionP roPilotAdjustSM. gif

                                OK. On to the procedure!

                                1) Warm up the engine to full operating temp.

                                2) Turn up your idle a few hundred RPM using the throttle stop screw (basically you want a fast idle). This will make it easier to hear small changes in RPM. Watch for overheating- -pointing a big shop fan at your engine will help it from getting too hot during the fast idling. The whole procedure shouldn't take too long though.

                                Each time you change the screw setting 1/4 or 1/2 turn or so, wait about 5 seconds to let the idle speed normalize. It usually take the carb and engine a moment to react to the change.

                                3) Turn the fuel screw IN until the idle starts to drop and miss. The engine should die if you bottom out the screw. Your pilot jet is too big if it doesn't die when the screw is bottomed out--it should die before it gets that far in.

                                4) Then begin turning the fuel screw OUT. The idle should peak and become smooth. Keep going and look for the idle to begin to drop/miss again.

                                5) The goal is to find the setting that provides the highest and smoothest idle. If it's unclear exactly were that point is then set to the midpoint between step #3 and step #4. For example, if the idle starts to drop at 1 turn out and starts to drop at 2 1/2 turns out then 1 3/4 of a turn out should be the correct setting.

                                If the peak/smoothest RPM is reached somewhere between 1-3 turns then your pilot jet is correct (the 1-3 turns applies to most carb types). If you end up less than 1 turn out then your pilot jet is too big and you need a smaller one. If you end up more than three turns out or the fuel screw seems to make little difference as you continue turning it out than you need to go up (bigger) on your pilot jet.

                                To re-emphisize: If the idle never drops when you're turning the fuel screw in, you need a smaller pilot jet. If the idle never drops when you're turning the fuel screw out, you need a bigger pilot jet.

                                Typical fuel screw settings are in the 1 1/2 to 2 1/2 range.

                                6) Once you've got the fuel screw set, re-adjust your throttle stop screw (idle screw) to an appropriate idle speed.

                                And that's it! Your pilot circuit is now VERY close to ideal. From here you can experiment with how small adjustments affect low-end (i.e. small throttle openings) response and make adjustments for weather. The hardest part is usually gaining access to the screw while the engine is running. Also, you may really have to listen carefully to detect the rpm changes in the idle. 100 or 200 rpm differences can be tough to detect when the change happens over several seconds.http://www.exriders .com/archive/ topic/229923- 1.html
                                 
                                 
                           
                 
       


 
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: pilot adjustment

David-776
 Hi Bill. I was in Rough and Ready about a month ago. I should have looked you up. Cheers. Dave Allen.
--- In [hidden email], "Bill Stigall" <bill.stigall@...> wrote:

>
> Too cold for me!  I am in the Sierra Foothills of Northern California near Nevada City.
>
> Bill
>   ----- Original Message -----
>   From: William Hall
>   To: [hidden email]
>   Sent: Monday, May 10, 2010 6:57 PM
>   Subject: Re: [ViragoTech] pilot adjustment
>
>
>    
>         Flossmoor, Il, a South suburb of Chicago. Mike
>
>         --- On Mon, 5/10/10, Bill Stigall <bill.stigall@...> wrote:
>
>
>           From: Bill Stigall <bill.stigall@...>
>           Subject: Re: [ViragoTech] pilot adjustment
>           To: [hidden email]
>           Date: Monday, May 10, 2010, 8:41 PM
>
>
>            
>           
>           Where are you located?
>           Bill
>             ----- Original Message -----
>             From: William Hall
>             To: ViragoTech@yahoogro ups.com
>             Sent: Monday, May 10, 2010 6:24 PM
>             Subject: Re: [ViragoTech] pilot adjustment
>
>
>              
>                   I've used seafoam for years in everything. I do try to take care of my bikes. When I sold my 86 he bought it sight unseen and paid to have it shipped and couldn't believe how nice it was. Thanks, Mike
>
>                   --- On Mon, 5/10/10, Bill's Personal <bill.stigall@ sbcglobal. net> wrote:
>
>
>                     From: Bill's Personal <bill.stigall@ sbcglobal. net>
>                     Subject: Re: [ViragoTech] pilot adjustment
>                     To: ViragoTech@yahoogro ups.com
>                     Date: Monday, May 10, 2010, 10:06 AM
>
>
>                      
>                     
>                     Mike,
>                     You can take your time and keep tweaking it until it is perfect, (patience), or if its running good and getting good gas mileage, you can just go riding and leave it be until a problem appears and then deal with it. I go with the latter...... ... My '83 XV920 could probably be tweaked up a bit, but it runs good, gets good gas mileage, (40-45 city, 48-50 highway), so I just leave it alone and ride it. I am running a little rich, but on these bikes, rich is better than lean as fuel helps some in cooling the engine and particularly the rear cylinder.
>                     The key, IMHO, is to keep up the regular maintenance. Follow the maintenance and service maintenance instructions in your manual. I change plugs once per season and change oil and filter every 1500 miles. I have been using Castrol GTX 20w50, but with the next change, I will switch to Mobil 1 15w50 Synthetic since it has better cooling properties. I also run a can of SeaFoam through the gas tank twice per season, (1/2 can with a full tank), to keep my carbs clean and functioning well.
>                     So its up to you how far you want to go with tuning.
>
>                     Good and Safe Riding,
>                     Bill
>
>                       ----- Original Message -----
>                       From: William Hall
>                       To: ViragoTech@yahoogro ups.com
>                       Sent: Monday, May 10, 2010 5:07 AM
>                       Subject: Re: [ViragoTech] pilot adjustment
>
>
>                        
>                             Ahh yes patience, sometimes thats had to come by. But I will try. Thanks, Mike
>
>                             --- On Sun, 5/9/10, Bill's Personal <bill.stigall@ sbcglobal. net> wrote:
>
>
>                               From: Bill's Personal <bill.stigall@ sbcglobal. net>
>                               Subject: Re: [ViragoTech] pilot adjustment
>                               To: ViragoTech@yahoogro ups.com
>                               Date: Sunday, May 9, 2010, 9:30 PM
>
>
>                                
>                               
>                               As you are probably aware, the plug color should be tan or both cylinders. If they are black, you will need to lean that carb out a little. Try 1/4 turn at a time and then run it again. If the plug color is white, then you will need to turn the pilot screw out and try again. The color may be different on each cylinder. On Mikuni carbs, the pilot jet handles idle and low speed, however when the engine speed picks up, the pilot jet is wide open and works in combination with the main jet to get the mixture for higher engine speeds. Therefore minor adjustments in high speed mixture can be made with the pilot screw.
>                               Once you have both carbs running with the correct mixture, (plug color tan on both cylinders), you should be good to go. Have patience, this can take a little while to get them dialed in.
>
>                               Bill
>
>                                 ----- Original Message -----
>                                 From: William Hall
>                                 To: ViragoTech@yahoogro ups.com
>                                 Sent: Sunday, May 09, 2010 5:50 PM
>                                 Subject: Re: [ViragoTech] pilot adjustment
>
>
>                                  
>                                 Well I set them both at 3 and no more backfire. I cleaned the plugs so after a bit of ridin I'll check them again. nstead of raising the rear of the gas tank I raised the front and it gave as much clearance as possible with the frame and wires in the way.Thanks, Mike
>
>                                 --- On Sun, 5/9/10, William Hall <wmh1968@att. net> wrote:
>
>
>                                 From: William Hall <wmh1968@att. net>
>                                 Subject: Re: [ViragoTech] pilot adjustment
>                                 To: ViragoTech@yahoogro ups.com
>                                 Date: Sunday, May 9, 2010, 10:37 AM
>
>
>                                  
>                                 I've got Mikunis. I did this years ago on my 86-1100 and it never died even all the way in and I don't think it did much all the way out either but I'm gonna play with it. I forget, how do you turn the idele up on MIkunis? I had put them on my 86 when I removed my KJS single carb. Thanks, Mike
>
>                                 --- On Sun, 5/9/10, Bill's Personal <bill.stigall@ sbcglobal. net> wrote:Bill,
>                                 The base setting is 2.5 turns out from a soft seat. Every bike is different, so you have to adjust each carb until you get the best idle. In is leaner; out is richer...... .... As for the procedure; it is a good general procedure with the exception of adjusting the idle speed and the jet size..... On the Virago you need to consider the sync of the carbs if you try and adjust the idle speed. Hitachi's are individually adjustable for idle speed, I am not sure about Mikuni's. If you adjust your idle up, you may have to re-sync your carbs. The turn the pilot screw all the way in, make sure you don't tighten it down tight or it will damage both the needle and the seat. On a single cylinder engine, it might die when you lean it out, but that isn't necessarily true on a twin, it should slow the idle and perhaps start hitting on one cylinder. A better read on if you are running to rich or too lean it the color of your spark plugs.
>                                 The offset screw driver is a good idea. Also a flexible screwdriver will work as well. The pilot screws are on top of the carb throat in the Mikuni carb, so you will have to raise the fuel tank or remove it and use a bottle with some fuel in it and a hose connected to the carbs. The latter is the easier way IMHO.
>
>                                 Bill
>                                 ----- Original Message -----
>                                 From: William Hall
>                                 To: ViragoTech@yahoogro ups.com
>                                 Sent: Sunday, May 09, 2010 7:49 AM
>                                 Subject: [ViragoTech] pilot adjustment
>
>
>                                  
>                                 Here is a link and the verbage for setting the pilot. Does this sound good for our bikes? Seems like I remember the factory setting was 2.5 turns. What do you think? I got my ais removed and everything capped and now there is only a slight backfire at idle. With the Mikunis it's a pain to get at the screws. Does anyone use a 90 degree screwdriver and if so where did you get it and how much and des it reach both screw. Thanks, Mike
>
>                                 This is my prefered method of finding the proper setting for the pilot screw (aka fuel screw). This method can also indicate if your pilot jet is too big or too small. Towards the bottom is an explination about the difference between fuel screws and air screws.
>
>                                 You'll need to be able to access the fuel screw while the engine is running. This can be quite difficult on many carbs. FCRs have aftermarket fuel screws that are longer which helps. On a stock 400EX carb (and many others) I use a 90 degree screwdriver. I bit the bullet and bought this one from MotionPro. It works well but I'm sure there are others available. If you're lucky, your fuel screw is easily reached with a normal screw driver.
>
>                                 http://www.azjetski .com/catalog/ images/03MotionP roPilotAdjustSM. gif
>
>                                 OK. On to the procedure!
>
>                                 1) Warm up the engine to full operating temp.
>
>                                 2) Turn up your idle a few hundred RPM using the throttle stop screw (basically you want a fast idle). This will make it easier to hear small changes in RPM. Watch for overheating- -pointing a big shop fan at your engine will help it from getting too hot during the fast idling. The whole procedure shouldn't take too long though.
>
>                                 Each time you change the screw setting 1/4 or 1/2 turn or so, wait about 5 seconds to let the idle speed normalize. It usually take the carb and engine a moment to react to the change.
>
>                                 3) Turn the fuel screw IN until the idle starts to drop and miss. The engine should die if you bottom out the screw. Your pilot jet is too big if it doesn't die when the screw is bottomed out--it should die before it gets that far in.
>
>                                 4) Then begin turning the fuel screw OUT. The idle should peak and become smooth. Keep going and look for the idle to begin to drop/miss again.
>
>                                 5) The goal is to find the setting that provides the highest and smoothest idle. If it's unclear exactly were that point is then set to the midpoint between step #3 and step #4. For example, if the idle starts to drop at 1 turn out and starts to drop at 2 1/2 turns out then 1 3/4 of a turn out should be the correct setting.
>
>                                 If the peak/smoothest RPM is reached somewhere between 1-3 turns then your pilot jet is correct (the 1-3 turns applies to most carb types). If you end up less than 1 turn out then your pilot jet is too big and you need a smaller one. If you end up more than three turns out or the fuel screw seems to make little difference as you continue turning it out than you need to go up (bigger) on your pilot jet.
>
>                                 To re-emphisize: If the idle never drops when you're turning the fuel screw in, you need a smaller pilot jet. If the idle never drops when you're turning the fuel screw out, you need a bigger pilot jet.
>
>                                 Typical fuel screw settings are in the 1 1/2 to 2 1/2 range.
>
>                                 6) Once you've got the fuel screw set, re-adjust your throttle stop screw (idle screw) to an appropriate idle speed.
>
>                                 And that's it! Your pilot circuit is now VERY close to ideal. From here you can experiment with how small adjustments affect low-end (i.e. small throttle openings) response and make adjustments for weather. The hardest part is usually gaining access to the screw while the engine is running. Also, you may really have to listen carefully to detect the rpm changes in the idle. 100 or 200 rpm differences can be tough to detect when the change happens over several seconds.http://www.exriders .com/archive/ topic/229923- 1.html
>


Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: Re: pilot adjustment

bill.stigall
Hey Dave,
R&R is about 3 miles down the road from my place. Perhaps we can get together this summer. I will be taking a trip or two over the top when the weather warms a bit. Have to put a new rear tire on the Virago. Have it setting here, but am not sure I want to attempt changing it myself. I went with a Kenda 671 this time. The Metzlers that were on it were too expensive for me right now. Someone put a front tire on the rear and it didn't wear very well.
If you are in the area again, drop me a note and we can get together.

Bill

  ----- Original Message -----
  From: David
  To: [hidden email]
  Sent: Monday, May 10, 2010 7:24 PM
  Subject: [ViragoTech] Re: pilot adjustment


   
  Hi Bill. I was in Rough and Ready about a month ago. I should have looked you up. Cheers. Dave Allen.
  --- In [hidden email], "Bill Stigall" <bill.stigall@...> wrote:
  >
  > Too cold for me! I am in the Sierra Foothills of Northern California near Nevada City.
  >
  > Bill
  > ----- Original Message -----
  > From: William Hall
  > To: [hidden email]
  > Sent: Monday, May 10, 2010 6:57 PM
  > Subject: Re: [ViragoTech] pilot adjustment
  >
  >
  >
  > Flossmoor, Il, a South suburb of Chicago. Mike
  >
  > --- On Mon, 5/10/10, Bill Stigall <bill.stigall@...> wrote:
  >
  >
  > From: Bill Stigall <bill.stigall@...>
  > Subject: Re: [ViragoTech] pilot adjustment
  > To: [hidden email]
  > Date: Monday, May 10, 2010, 8:41 PM
  >
  >
  >
  > 
  > Where are you located?
  > Bill
  > ----- Original Message -----
  > From: William Hall
  > To: ViragoTech@yahoogro ups.com
  > Sent: Monday, May 10, 2010 6:24 PM
  > Subject: Re: [ViragoTech] pilot adjustment
  >
  >
  >
  > I've used seafoam for years in everything. I do try to take care of my bikes. When I sold my 86 he bought it sight unseen and paid to have it shipped and couldn't believe how nice it was. Thanks, Mike
  >
  > --- On Mon, 5/10/10, Bill's Personal <bill.stigall@ sbcglobal. net> wrote:
  >
  >
  > From: Bill's Personal <bill.stigall@ sbcglobal. net>
  > Subject: Re: [ViragoTech] pilot adjustment
  > To: ViragoTech@yahoogro ups.com
  > Date: Monday, May 10, 2010, 10:06 AM
  >
  >
  >
  > 
  > Mike,
  > You can take your time and keep tweaking it until it is perfect, (patience), or if its running good and getting good gas mileage, you can just go riding and leave it be until a problem appears and then deal with it. I go with the latter...... ... My '83 XV920 could probably be tweaked up a bit, but it runs good, gets good gas mileage, (40-45 city, 48-50 highway), so I just leave it alone and ride it. I am running a little rich, but on these bikes, rich is better than lean as fuel helps some in cooling the engine and particularly the rear cylinder.
  > The key, IMHO, is to keep up the regular maintenance. Follow the maintenance and service maintenance instructions in your manual. I change plugs once per season and change oil and filter every 1500 miles. I have been using Castrol GTX 20w50, but with the next change, I will switch to Mobil 1 15w50 Synthetic since it has better cooling properties. I also run a can of SeaFoam through the gas tank twice per season, (1/2 can with a full tank), to keep my carbs clean and functioning well.
  > So its up to you how far you want to go with tuning.
  >
  > Good and Safe Riding,
  > Bill
  >
  > ----- Original Message -----
  > From: William Hall
  > To: ViragoTech@yahoogro ups.com
  > Sent: Monday, May 10, 2010 5:07 AM
  > Subject: Re: [ViragoTech] pilot adjustment
  >
  >
  >
  > Ahh yes patience, sometimes thats had to come by. But I will try. Thanks, Mike
  >
  > --- On Sun, 5/9/10, Bill's Personal <bill.stigall@ sbcglobal. net> wrote:
  >
  >
  > From: Bill's Personal <bill.stigall@ sbcglobal. net>
  > Subject: Re: [ViragoTech] pilot adjustment
  > To: ViragoTech@yahoogro ups.com
  > Date: Sunday, May 9, 2010, 9:30 PM
  >
  >
  >
  > 
  > As you are probably aware, the plug color should be tan or both cylinders. If they are black, you will need to lean that carb out a little. Try 1/4 turn at a time and then run it again. If the plug color is white, then you will need to turn the pilot screw out and try again. The color may be different on each cylinder. On Mikuni carbs, the pilot jet handles idle and low speed, however when the engine speed picks up, the pilot jet is wide open and works in combination with the main jet to get the mixture for higher engine speeds. Therefore minor adjustments in high speed mixture can be made with the pilot screw.
  > Once you have both carbs running with the correct mixture, (plug color tan on both cylinders), you should be good to go. Have patience, this can take a little while to get them dialed in.
  >
  > Bill
  >
  > ----- Original Message -----
  > From: William Hall
  > To: ViragoTech@yahoogro ups.com
  > Sent: Sunday, May 09, 2010 5:50 PM
  > Subject: Re: [ViragoTech] pilot adjustment
  >
  >
  >
  > Well I set them both at 3 and no more backfire. I cleaned the plugs so after a bit of ridin I'll check them again. nstead of raising the rear of the gas tank I raised the front and it gave as much clearance as possible with the frame and wires in the way.Thanks, Mike
  >
  > --- On Sun, 5/9/10, William Hall <wmh1968@att. net> wrote:
  >
  >
  > From: William Hall <wmh1968@att. net>
  > Subject: Re: [ViragoTech] pilot adjustment
  > To: ViragoTech@yahoogro ups.com
  > Date: Sunday, May 9, 2010, 10:37 AM
  >
  >
  >
  > I've got Mikunis. I did this years ago on my 86-1100 and it never died even all the way in and I don't think it did much all the way out either but I'm gonna play with it. I forget, how do you turn the idele up on MIkunis? I had put them on my 86 when I removed my KJS single carb. Thanks, Mike
  >
  > --- On Sun, 5/9/10, Bill's Personal <bill.stigall@ sbcglobal. net> wrote:Bill,
  > The base setting is 2.5 turns out from a soft seat. Every bike is different, so you have to adjust each carb until you get the best idle. In is leaner; out is richer...... .... As for the procedure; it is a good general procedure with the exception of adjusting the idle speed and the jet size..... On the Virago you need to consider the sync of the carbs if you try and adjust the idle speed. Hitachi's are individually adjustable for idle speed, I am not sure about Mikuni's. If you adjust your idle up, you may have to re-sync your carbs. The turn the pilot screw all the way in, make sure you don't tighten it down tight or it will damage both the needle and the seat. On a single cylinder engine, it might die when you lean it out, but that isn't necessarily true on a twin, it should slow the idle and perhaps start hitting on one cylinder. A better read on if you are running to rich or too lean it the color of your spark plugs.
  > The offset screw driver is a good idea. Also a flexible screwdriver will work as well. The pilot screws are on top of the carb throat in the Mikuni carb, so you will have to raise the fuel tank or remove it and use a bottle with some fuel in it and a hose connected to the carbs. The latter is the easier way IMHO.
  >
  > Bill
  > ----- Original Message -----
  > From: William Hall
  > To: ViragoTech@yahoogro ups.com
  > Sent: Sunday, May 09, 2010 7:49 AM
  > Subject: [ViragoTech] pilot adjustment
  >
  >
  >
  > Here is a link and the verbage for setting the pilot. Does this sound good for our bikes? Seems like I remember the factory setting was 2.5 turns. What do you think? I got my ais removed and everything capped and now there is only a slight backfire at idle. With the Mikunis it's a pain to get at the screws. Does anyone use a 90 degree screwdriver and if so where did you get it and how much and des it reach both screw. Thanks, Mike
  >
  > This is my prefered method of finding the proper setting for the pilot screw (aka fuel screw). This method can also indicate if your pilot jet is too big or too small. Towards the bottom is an explination about the difference between fuel screws and air screws.
  >
  > You'll need to be able to access the fuel screw while the engine is running. This can be quite difficult on many carbs. FCRs have aftermarket fuel screws that are longer which helps. On a stock 400EX carb (and many others) I use a 90 degree screwdriver. I bit the bullet and bought this one from MotionPro. It works well but I'm sure there are others available. If you're lucky, your fuel screw is easily reached with a normal screw driver.
  >
  > http://www.azjetski .com/catalog/ images/03MotionP roPilotAdjustSM. gif
  >
  > OK. On to the procedure!
  >
  > 1) Warm up the engine to full operating temp.
  >
  > 2) Turn up your idle a few hundred RPM using the throttle stop screw (basically you want a fast idle). This will make it easier to hear small changes in RPM. Watch for overheating- -pointing a big shop fan at your engine will help it from getting too hot during the fast idling. The whole procedure shouldn't take too long though.
  >
  > Each time you change the screw setting 1/4 or 1/2 turn or so, wait about 5 seconds to let the idle speed normalize. It usually take the carb and engine a moment to react to the change.
  >
  > 3) Turn the fuel screw IN until the idle starts to drop and miss. The engine should die if you bottom out the screw. Your pilot jet is too big if it doesn't die when the screw is bottomed out--it should die before it gets that far in.
  >
  > 4) Then begin turning the fuel screw OUT. The idle should peak and become smooth. Keep going and look for the idle to begin to drop/miss again.
  >
  > 5) The goal is to find the setting that provides the highest and smoothest idle. If it's unclear exactly were that point is then set to the midpoint between step #3 and step #4. For example, if the idle starts to drop at 1 turn out and starts to drop at 2 1/2 turns out then 1 3/4 of a turn out should be the correct setting.
  >
  > If the peak/smoothest RPM is reached somewhere between 1-3 turns then your pilot jet is correct (the 1-3 turns applies to most carb types). If you end up less than 1 turn out then your pilot jet is too big and you need a smaller one. If you end up more than three turns out or the fuel screw seems to make little difference as you continue turning it out than you need to go up (bigger) on your pilot jet.
  >
  > To re-emphisize: If the idle never drops when you're turning the fuel screw in, you need a smaller pilot jet. If the idle never drops when you're turning the fuel screw out, you need a bigger pilot jet.
  >
  > Typical fuel screw settings are in the 1 1/2 to 2 1/2 range.
  >
  > 6) Once you've got the fuel screw set, re-adjust your throttle stop screw (idle screw) to an appropriate idle speed.
  >
  > And that's it! Your pilot circuit is now VERY close to ideal. From here you can experiment with how small adjustments affect low-end (i.e. small throttle openings) response and make adjustments for weather. The hardest part is usually gaining access to the screw while the engine is running. Also, you may really have to listen carefully to detect the rpm changes in the idle. 100 or 200 rpm differences can be tough to detect when the change happens over several seconds.http://www.exriders .com/archive/ topic/229923- 1.html
  >



 
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: pilot adjustment

David-776

Hi Bill. I will do that, next time I head that way. We were learning how to pan gold near R&R. I will be gone most of June but if you are on this side of the hill this summer let me know and we can do lunch, my treat. Cheers. Dave Allen.
--- In [hidden email], "Bill's Personal" <bill.stigall@...> wrote:

>
> Hey Dave,
> R&R is about 3 miles down the road from my place. Perhaps we can get together this summer. I will be taking a trip or two over the top when the weather warms a bit. Have to put a new rear tire on the Virago. Have it setting here, but am not sure I want to attempt changing it myself. I went with a Kenda 671 this time. The Metzlers that were on it were too expensive for me right now. Someone put a front tire on the rear and it didn't wear very well.
> If you are in the area again, drop me a note and we can get together.
>
> Bill
>
>   ----- Original Message -----
>   From: David
>   To: [hidden email]
>   Sent: Monday, May 10, 2010 7:24 PM
>   Subject: [ViragoTech] Re: pilot adjustment
>
>
>    
>   Hi Bill. I was in Rough and Ready about a month ago. I should have looked you up. Cheers. Dave Allen.
>   --- In [hidden email], "Bill Stigall" <bill.stigall@> wrote:
>   >
>   > Too cold for me! I am in the Sierra Foothills of Northern California near Nevada City.
>   >
>   > Bill
>   > ----- Original Message -----
>   > From: William Hall
>   > To: [hidden email]
>   > Sent: Monday, May 10, 2010 6:57 PM
>   > Subject: Re: [ViragoTech] pilot adjustment
>   >
>   >
>   >
>   > Flossmoor, Il, a South suburb of Chicago. Mike
>   >
>   > --- On Mon, 5/10/10, Bill Stigall <bill.stigall@> wrote:
>   >
>   >
>   > From: Bill Stigall <bill.stigall@>
>   > Subject: Re: [ViragoTech] pilot adjustment
>   > To: [hidden email]
>   > Date: Monday, May 10, 2010, 8:41 PM
>   >
>   >
>   >
>   > 
>   > Where are you located?
>   > Bill
>   > ----- Original Message -----
>   > From: William Hall
>   > To: ViragoTech@yahoogro ups.com
>   > Sent: Monday, May 10, 2010 6:24 PM
>   > Subject: Re: [ViragoTech] pilot adjustment
>   >
>   >
>   >
>   > I've used seafoam for years in everything. I do try to take care of my bikes. When I sold my 86 he bought it sight unseen and paid to have it shipped and couldn't believe how nice it was. Thanks, Mike
>   >
>   > --- On Mon, 5/10/10, Bill's Personal <bill.stigall@ sbcglobal. net> wrote:
>   >
>   >
>   > From: Bill's Personal <bill.stigall@ sbcglobal. net>
>   > Subject: Re: [ViragoTech] pilot adjustment
>   > To: ViragoTech@yahoogro ups.com
>   > Date: Monday, May 10, 2010, 10:06 AM
>   >
>   >
>   >
>   > 
>   > Mike,
>   > You can take your time and keep tweaking it until it is perfect, (patience), or if its running good and getting good gas mileage, you can just go riding and leave it be until a problem appears and then deal with it. I go with the latter...... ... My '83 XV920 could probably be tweaked up a bit, but it runs good, gets good gas mileage, (40-45 city, 48-50 highway), so I just leave it alone and ride it. I am running a little rich, but on these bikes, rich is better than lean as fuel helps some in cooling the engine and particularly the rear cylinder.
>   > The key, IMHO, is to keep up the regular maintenance. Follow the maintenance and service maintenance instructions in your manual. I change plugs once per season and change oil and filter every 1500 miles. I have been using Castrol GTX 20w50, but with the next change, I will switch to Mobil 1 15w50 Synthetic since it has better cooling properties. I also run a can of SeaFoam through the gas tank twice per season, (1/2 can with a full tank), to keep my carbs clean and functioning well.
>   > So its up to you how far you want to go with tuning.
>   >
>   > Good and Safe Riding,
>   > Bill
>   >
>   > ----- Original Message -----
>   > From: William Hall
>   > To: ViragoTech@yahoogro ups.com
>   > Sent: Monday, May 10, 2010 5:07 AM
>   > Subject: Re: [ViragoTech] pilot adjustment
>   >
>   >
>   >
>   > Ahh yes patience, sometimes thats had to come by. But I will try. Thanks, Mike
>   >
>   > --- On Sun, 5/9/10, Bill's Personal <bill.stigall@ sbcglobal. net> wrote:
>   >
>   >
>   > From: Bill's Personal <bill.stigall@ sbcglobal. net>
>   > Subject: Re: [ViragoTech] pilot adjustment
>   > To: ViragoTech@yahoogro ups.com
>   > Date: Sunday, May 9, 2010, 9:30 PM
>   >
>   >
>   >
>   > 
>   > As you are probably aware, the plug color should be tan or both cylinders. If they are black, you will need to lean that carb out a little. Try 1/4 turn at a time and then run it again. If the plug color is white, then you will need to turn the pilot screw out and try again. The color may be different on each cylinder. On Mikuni carbs, the pilot jet handles idle and low speed, however when the engine speed picks up, the pilot jet is wide open and works in combination with the main jet to get the mixture for higher engine speeds. Therefore minor adjustments in high speed mixture can be made with the pilot screw.
>   > Once you have both carbs running with the correct mixture, (plug color tan on both cylinders), you should be good to go. Have patience, this can take a little while to get them dialed in.
>   >
>   > Bill
>   >
>   > ----- Original Message -----
>   > From: William Hall
>   > To: ViragoTech@yahoogro ups.com
>   > Sent: Sunday, May 09, 2010 5:50 PM
>   > Subject: Re: [ViragoTech] pilot adjustment
>   >
>   >
>   >
>   > Well I set them both at 3 and no more backfire. I cleaned the plugs so after a bit of ridin I'll check them again. nstead of raising the rear of the gas tank I raised the front and it gave as much clearance as possible with the frame and wires in the way.Thanks, Mike
>   >
>   > --- On Sun, 5/9/10, William Hall <wmh1968@att. net> wrote:
>   >
>   >
>   > From: William Hall <wmh1968@att. net>
>   > Subject: Re: [ViragoTech] pilot adjustment
>   > To: ViragoTech@yahoogro ups.com
>   > Date: Sunday, May 9, 2010, 10:37 AM
>   >
>   >
>   >
>   > I've got Mikunis. I did this years ago on my 86-1100 and it never died even all the way in and I don't think it did much all the way out either but I'm gonna play with it. I forget, how do you turn the idele up on MIkunis? I had put them on my 86 when I removed my KJS single carb. Thanks, Mike
>   >
>   > --- On Sun, 5/9/10, Bill's Personal <bill.stigall@ sbcglobal. net> wrote:Bill,
>   > The base setting is 2.5 turns out from a soft seat. Every bike is different, so you have to adjust each carb until you get the best idle. In is leaner; out is richer...... .... As for the procedure; it is a good general procedure with the exception of adjusting the idle speed and the jet size..... On the Virago you need to consider the sync of the carbs if you try and adjust the idle speed. Hitachi's are individually adjustable for idle speed, I am not sure about Mikuni's. If you adjust your idle up, you may have to re-sync your carbs. The turn the pilot screw all the way in, make sure you don't tighten it down tight or it will damage both the needle and the seat. On a single cylinder engine, it might die when you lean it out, but that isn't necessarily true on a twin, it should slow the idle and perhaps start hitting on one cylinder. A better read on if you are running to rich or too lean it the color of your spark plugs.
>   > The offset screw driver is a good idea. Also a flexible screwdriver will work as well. The pilot screws are on top of the carb throat in the Mikuni carb, so you will have to raise the fuel tank or remove it and use a bottle with some fuel in it and a hose connected to the carbs. The latter is the easier way IMHO.
>   >
>   > Bill
>   > ----- Original Message -----
>   > From: William Hall
>   > To: ViragoTech@yahoogro ups.com
>   > Sent: Sunday, May 09, 2010 7:49 AM
>   > Subject: [ViragoTech] pilot adjustment
>   >
>   >
>   >
>   > Here is a link and the verbage for setting the pilot. Does this sound good for our bikes? Seems like I remember the factory setting was 2.5 turns. What do you think? I got my ais removed and everything capped and now there is only a slight backfire at idle. With the Mikunis it's a pain to get at the screws. Does anyone use a 90 degree screwdriver and if so where did you get it and how much and des it reach both screw. Thanks, Mike
>   >
>   > This is my prefered method of finding the proper setting for the pilot screw (aka fuel screw). This method can also indicate if your pilot jet is too big or too small. Towards the bottom is an explination about the difference between fuel screws and air screws.
>   >
>   > You'll need to be able to access the fuel screw while the engine is running. This can be quite difficult on many carbs. FCRs have aftermarket fuel screws that are longer which helps. On a stock 400EX carb (and many others) I use a 90 degree screwdriver. I bit the bullet and bought this one from MotionPro. It works well but I'm sure there are others available. If you're lucky, your fuel screw is easily reached with a normal screw driver.
>   >
>   > http://www.azjetski .com/catalog/ images/03MotionP roPilotAdjustSM. gif
>   >
>   > OK. On to the procedure!
>   >
>   > 1) Warm up the engine to full operating temp.
>   >
>   > 2) Turn up your idle a few hundred RPM using the throttle stop screw (basically you want a fast idle). This will make it easier to hear small changes in RPM. Watch for overheating- -pointing a big shop fan at your engine will help it from getting too hot during the fast idling. The whole procedure shouldn't take too long though.
>   >
>   > Each time you change the screw setting 1/4 or 1/2 turn or so, wait about 5 seconds to let the idle speed normalize. It usually take the carb and engine a moment to react to the change.
>   >
>   > 3) Turn the fuel screw IN until the idle starts to drop and miss. The engine should die if you bottom out the screw. Your pilot jet is too big if it doesn't die when the screw is bottomed out--it should die before it gets that far in.
>   >
>   > 4) Then begin turning the fuel screw OUT. The idle should peak and become smooth. Keep going and look for the idle to begin to drop/miss again.
>   >
>   > 5) The goal is to find the setting that provides the highest and smoothest idle. If it's unclear exactly were that point is then set to the midpoint between step #3 and step #4. For example, if the idle starts to drop at 1 turn out and starts to drop at 2 1/2 turns out then 1 3/4 of a turn out should be the correct setting.
>   >
>   > If the peak/smoothest RPM is reached somewhere between 1-3 turns then your pilot jet is correct (the 1-3 turns applies to most carb types). If you end up less than 1 turn out then your pilot jet is too big and you need a smaller one. If you end up more than three turns out or the fuel screw seems to make little difference as you continue turning it out than you need to go up (bigger) on your pilot jet.
>   >
>   > To re-emphisize: If the idle never drops when you're turning the fuel screw in, you need a smaller pilot jet. If the idle never drops when you're turning the fuel screw out, you need a bigger pilot jet.
>   >
>   > Typical fuel screw settings are in the 1 1/2 to 2 1/2 range.
>   >
>   > 6) Once you've got the fuel screw set, re-adjust your throttle stop screw (idle screw) to an appropriate idle speed.
>   >
>   > And that's it! Your pilot circuit is now VERY close to ideal. From here you can experiment with how small adjustments affect low-end (i.e. small throttle openings) response and make adjustments for weather. The hardest part is usually gaining access to the screw while the engine is running. Also, you may really have to listen carefully to detect the rpm changes in the idle. 100 or 200 rpm differences can be tough to detect when the change happens over several seconds.http://www.exriders .com/archive/ topic/229923- 1.html
>   >
>


Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: Re: pilot adjustment

bill.stigall
 

Hey Dave, Sounds great. We have to get rid of winter before I will be going over the hill. At this rate, that may be July. Learning how to pan gold is much easier than finding it, I think. Bill ----- Original Message ----- From: David To: ViragoTech@yahoogroups.com Sent: Wednesday, May 12, 2010 6:37 PM Subject: [ViragoTech] Re: pilot adjustment Hi Bill. I will do that, next time I head that way. We were learning how to pan gold near R&R. I will be gone most of June but if you are on this side of the hill this summer let me know and we can do lunch, my treat. Cheers. Dave Allen. --- In ViragoTech@yahoogroups.com, "Bill's Personal" wrote: > > Hey Dave, > R&R is about 3 miles down the road from my place. Perhaps we can get together this summer. I will be taking a trip or two over the top when the weather warms a bit. Have to put a new rear tire on the Virago. Have it setting here, but am not sure I want to attempt changing it myself. I went with a Kenda 671 this time. The Metzlers that were on it were too expensive for me right now. Someone put a front tire on the rear and it didn't wear very well. > If you are in the area again, drop me a note and we can get together. > > Bill > > ----- Original Message ----- > From: David > To: ViragoTech@yahoogroups.com > Sent: Monday, May 10, 2010 7:24 PM > Subject: [ViragoTech] Re: pilot adjustment > > > > Hi Bill. I was in Rough and Ready about a month ago. I should have looked you up. Cheers. Dave Allen. > --- In ViragoTech@yahoogroups.com, "Bill Stigall" wrote: > > > > Too cold for me! I am in the Sierra Foothills of Northern California near Nevada City. > > > > Bill > > ----- Original Message ----- > > From: William Hall > > To: ViragoTech@yahoogroups.com > > Sent: Monday, May 10, 2010 6:57 PM > > Subject: Re: [ViragoTech] pilot adjustment > > > > > > > > Flossmoor, Il, a South suburb of Chicago. Mike > > > > --- On Mon, 5/10/10, Bill Stigall wrote: > > > > > > From: Bill Stigall > > Subject: Re: [ViragoTech] pilot adjustment > > To: ViragoTech@yahoogroups.com > > Date: Monday, May 10, 2010, 8:41 PM > > > > > > > >  > > Where are you located? > > Bill > > ----- Original Message ----- > > From: William Hall > > To: ViragoTech@yahoogro ups.com > > Sent: Monday, May 10, 2010 6:24 PM > > Subject: Re: [ViragoTech] pilot adjustment > > > > > > > > I've used seafoam for years in everything. I do try to take care of my bikes. When I sold my 86 he bought it sight unseen and paid to have it shipped and couldn't believe how nice it was. Thanks, Mike > > > > --- On Mon, 5/10/10, Bill's Personal wrote: > > > > > > From: Bill's Personal > > Subject: Re: [ViragoTech] pilot adjustment > > To: ViragoTech@yahoogro ups.com > > Date: Monday, May 10, 2010, 10:06 AM > > > > > > > >  > > Mike, > > You can take your time and keep tweaking it until it is perfect, (patience), or if its running good and getting good gas mileage, you can just go riding and leave it be until a problem appears and then deal with it. I go with the latter...... ... My '83 XV920 could probably be tweaked up a bit, but it runs good, gets good gas mileage, (40-45 city, 48-50 highway), so I just leave it alone and ride it. I am running a little rich, but on these bikes, rich is better than lean as fuel helps some in cooling the engine and particularly the rear cylinder. > > The key, IMHO, is to keep up the regular maintenance. Follow the maintenance and service maintenance instructions in your manual. I change plugs once per season and change oil and filter every 1500 miles. I have been using Castrol GTX 20w50, but with the next change, I will switch to Mobil 1 15w50 Synthetic since it has better cooling properties. I also run a can of SeaFoam through the gas tank twice per season, (1/2 can with a full tank), to keep my carbs clean and functioning well. > > So its up to you how far you want to go with tuning. > > > > Good and Safe Riding, > > Bill > > > > ----- Original Message ----- > > From: William Hall > > To: ViragoTech@yahoogro ups.com > > Sent: Monday, May 10, 2010 5:07 AM > > Subject: Re: [ViragoTech] pilot adjustment > > > > > > > > Ahh yes patience, sometimes thats had to come by. But I will try. Thanks, Mike > > > > --- On Sun, 5/9/10, Bill's Personal wrote: > > > > > > From: Bill's Personal > > Subject: Re: [ViragoTech] pilot adjustment > > To: ViragoTech@yahoogro ups.com > > Date: Sunday, May 9, 2010, 9:30 PM > > > > > > > >  > > As you are probably aware, the plug color should be tan or both cylinders. If they are black, you will need to lean that carb out a little. Try 1/4 turn at a time and then run it again. If the plug color is white, then you will need to turn the pilot screw out and try again. The color may be different on each cylinder. On Mikuni carbs, the pilot jet handles idle and low speed, however when the engine speed picks up, the pilot jet is wide open and works in combination with the main jet to get the mixture for higher engine speeds. Therefore minor adjustments in high speed mixture can be made with the pilot screw. > > Once you have both carbs running with the correct mixture, (plug color tan on both cylinders), you should be good to go. Have patience, this can take a little while to get them dialed in. > > > > Bill > > > > ----- Original Message ----- > > From: William Hall > > To: ViragoTech@yahoogro ups.com > > Sent: Sunday, May 09, 2010 5:50 PM > > Subject: Re: [ViragoTech] pilot adjustment > > > > > > > > Well I set them both at 3 and no more backfire. I cleaned the plugs so after a bit of ridin I'll check them again. nstead of raising the rear of the gas tank I raised the front and it gave as much clearance as possible with the frame and wires in the way.Thanks, Mike > > > > --- On Sun, 5/9/10, William Hall wrote: > > > > > > From: William Hall > > Subject: Re: [ViragoTech] pilot adjustment > > To: ViragoTech@yahoogro ups.com > > Date: Sunday, May 9, 2010, 10:37 AM > > > > > > > > I've got Mikunis. I did this years ago on my 86-1100 and it never died even all the way in and I don't think it did much all the way out either but I'm gonna play with it. I forget, how do you turn the idele up on MIkunis? I had put them on my 86 when I removed my KJS single carb. Thanks, Mike > > > > --- On Sun, 5/9/10, Bill's Personal wrote:Bill, > > The base setting is 2.5 turns out from a soft seat. Every bike is different, so you have to adjust each carb until you get the best idle. In is leaner; out is richer...... .... As for the procedure; it is a good general procedure with the exception of adjusting the idle speed and the jet size..... On the Virago you need to consider the sync of the carbs if you try and adjust the idle speed. Hitachi's are individually adjustable for idle speed, I am not sure about Mikuni's. If you adjust your idle up, you may have to re-sync your carbs. The turn the pilot screw all the way in, make sure you don't tighten it down tight or it will damage both the needle and the seat. On a single cylinder engine, it might die when you lean it out, but that isn't necessarily true on a twin, it should slow the idle and perhaps start hitting on one cylinder. A better read on if you are running to rich or too lean it the color of your spark plugs. > > The offset screw driver is a good idea. Also a flexible screwdriver will work as well. The pilot screws are on top of the carb throat in the Mikuni carb, so you will have to raise the fuel tank or remove it and use a bottle with some fuel in it and a hose connected to the carbs. The latter is the easier way IMHO. > > > > Bill > > ----- Original Message ----- > > From: William Hall > > To: ViragoTech@yahoogro ups.com > > Sent: Sunday, May 09, 2010 7:49 AM > > Subject: [ViragoTech] pilot adjustment > > > > > > > > Here is a link and the verbage for setting the pilot. Does this sound good for our bikes? Seems like I remember the factory setting was 2.5 turns. What do you think? I got my ais removed and everything capped and now there is only a slight backfire at idle. With the Mikunis it's a pain to get at the screws. Does anyone use a 90 degree screwdriver and if so where did you get it and how much and des it reach both screw. Thanks, Mike > > > > This is my prefered method of finding the proper setting for the pilot screw (aka fuel screw). This method can also indicate if your pilot jet is too big or too small. Towards the bottom is an explination about the difference between fuel screws and air screws. > > > > You'll need to be able to access the fuel screw while the engine is running. This can be quite difficult on many carbs. FCRs have aftermarket fuel screws that are longer which helps. On a stock 400EX carb (and many others) I use a 90 degree screwdriver. I bit the bullet and bought this one from MotionPro. It works well but I'm sure there are others available. If you're lucky, your fuel screw is easily reached with a normal screw driver. > > > > http://www.azjetski .com/catalog/ images/03MotionP roPilotAdjustSM. gif > > > > OK. On to the procedure! > > > > 1) Warm up the engine to full operating temp. > > > > 2) Turn up your idle a few hundred RPM using the throttle stop screw (basically you want a fast idle). This will make it easier to hear small changes in RPM. Watch for overheating- -pointing a big shop fan at your engine will help it from getting too hot during the fast idling. The whole procedure shouldn't take too long though. > > > > Each time you change the screw setting 1/4 or 1/2 turn or so, wait about 5 seconds to let the idle speed normalize. It usually take the carb and engine a moment to react to the change. > > > > 3) Turn the fuel screw IN until the idle starts to drop and miss. The engine should die if you bottom out the screw. Your pilot jet is too big if it doesn't die when the screw is bottomed out--it should die before it gets that far in. > > > > 4) Then begin turning the fuel screw OUT. The idle should peak and become smooth. Keep going and look for the idle to begin to drop/miss again. > > > > 5) The goal is to find the setting that provides the highest and smoothest idle. If it's unclear exactly were that point is then set to the midpoint between step #3 and step #4. For example, if the idle starts to drop at 1 turn out and starts to drop at 2 1/2 turns out then 1 3/4 of a turn out should be the correct setting. > > > > If the peak/smoothest RPM is reached somewhere between 1-3 turns then your pilot jet is correct (the 1-3 turns applies to most carb types). If you end up less than 1 turn out then your pilot jet is too big and you need a smaller one. If you end up more than three turns out or the fuel screw seems to make little difference as you continue turning it out than you need to go up (bigger) on your pilot jet. > > > > To re-emphisize: If the idle never drops when you're turning the fuel screw in, you need a smaller pilot jet. If the idle never drops when you're turning the fuel screw out, you need a bigger pilot jet. > > > > Typical fuel screw settings are in the 1 1/2 to 2 1/2 range. > > > > 6) Once you've got the fuel screw set, re-adjust your throttle stop screw (idle screw) to an appropriate idle speed. > > > > And that's it! Your pilot circuit is now VERY close to ideal. From here you can experiment with how small adjustments affect low-end (i.e. small throttle openings) response and make adjustments for weather. The hardest part is usually gaining access to the screw while the engine is running. Also, you may really have to listen carefully to detect the rpm changes in the idle. 100 or 200 rpm differences can be tough to detect when the change happens over several seconds.http://www.exriders .com/archive/ topic/229923- 1.html > > >

__._,_.___
Recent Activity:
MARKETPLACE

Stay on top of your group activity without leaving the page you're on - Get the Yahoo! Toolbar now.

<script language=javascript> if(window.yzq_d==null)window.yzq_d=new Object(); window.yzq_d['SGH8TmKImmg-']='&U=13c7n8c3r%2fN%3dSGH8TmKImmg-%2fC%3d493064.13983314.14041046.13298430%2fD%3dMKP1%2fB%3d6060255%2fV%3d1'; </script>

Get great advice about dogs and cats. Visit the Dog & Cat Answers Center.

<script language=javascript> if(window.yzq_d==null)window.yzq_d=new Object(); window.yzq_d['SWH8TmKImmg-']='&U=13cpsbgaa%2fN%3dSWH8TmKImmg-%2fC%3d493064.13814537.14041040.10835568%2fD%3dMKP1%2fB%3d6078812%2fV%3d1'; </script>

Hobbies & Activities Zone: Find others who share your passions! Explore new interests.

<script language=javascript> if(window.yzq_d==null)window.yzq_d=new Object(); window.yzq_d['SmH8TmKImmg-']='&U=13c8abbro%2fN%3dSmH8TmKImmg-%2fC%3d493064.14012770.13963757.13298430%2fD%3dMKP1%2fB%3d6015306%2fV%3d1'; </script>
.

__,_._,___
Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: pilot adjustment

David-776

Hi Bill. Telling the difference between it and pyrite is hard enough. Cheers. Dave Allen.
--- In [hidden email], "Bill's Personal" <bill.stigall@...> wrote:

>
> Hey Dave,
> Sounds great. We have to get rid of winter before I will be going over the hill. At this rate, that may be July.
> Learning how to pan gold is much easier than finding it, I think.
>
> Bill
>
>   ----- Original Message -----
>   From: David
>   To: [hidden email]
>   Sent: Wednesday, May 12, 2010 6:37 PM
>   Subject: [ViragoTech] Re: pilot adjustment
>
>
>    
>
>   Hi Bill. I will do that, next time I head that way. We were learning how to pan gold near R&R. I will be gone most of June but if you are on this side of the hill this summer let me know and we can do lunch, my treat. Cheers. Dave Allen.
>   --- In [hidden email], "Bill's Personal" <bill.stigall@> wrote:
>   >
>   > Hey Dave,
>   > R&R is about 3 miles down the road from my place. Perhaps we can get together this summer. I will be taking a trip or two over the top when the weather warms a bit. Have to put a new rear tire on the Virago. Have it setting here, but am not sure I want to attempt changing it myself. I went with a Kenda 671 this time. The Metzlers that were on it were too expensive for me right now. Someone put a front tire on the rear and it didn't wear very well.
>   > If you are in the area again, drop me a note and we can get together.
>   >
>   > Bill
>   >
>   > ----- Original Message -----
>   > From: David
>   > To: [hidden email]
>   > Sent: Monday, May 10, 2010 7:24 PM
>   > Subject: [ViragoTech] Re: pilot adjustment
>   >
>   >
>   >
>   > Hi Bill. I was in Rough and Ready about a month ago. I should have looked you up. Cheers. Dave Allen.
>   > --- In [hidden email], "Bill Stigall" <bill.stigall@> wrote:
>   > >
>   > > Too cold for me! I am in the Sierra Foothills of Northern California near Nevada City.
>   > >
>   > > Bill
>   > > ----- Original Message -----
>   > > From: William Hall
>   > > To: [hidden email]
>   > > Sent: Monday, May 10, 2010 6:57 PM
>   > > Subject: Re: [ViragoTech] pilot adjustment
>   > >
>   > >
>   > >
>   > > Flossmoor, Il, a South suburb of Chicago. Mike
>   > >
>   > > --- On Mon, 5/10/10, Bill Stigall <bill.stigall@> wrote:
>   > >
>   > >
>   > > From: Bill Stigall <bill.stigall@>
>   > > Subject: Re: [ViragoTech] pilot adjustment
>   > > To: [hidden email]
>   > > Date: Monday, May 10, 2010, 8:41 PM
>   > >
>   > >
>   > >
>   > > 
>   > > Where are you located?
>   > > Bill
>   > > ----- Original Message -----
>   > > From: William Hall
>   > > To: ViragoTech@yahoogro ups.com
>   > > Sent: Monday, May 10, 2010 6:24 PM
>   > > Subject: Re: [ViragoTech] pilot adjustment
>   > >
>   > >
>   > >
>   > > I've used seafoam for years in everything. I do try to take care of my bikes. When I sold my 86 he bought it sight unseen and paid to have it shipped and couldn't believe how nice it was. Thanks, Mike
>   > >
>   > > --- On Mon, 5/10/10, Bill's Personal <bill.stigall@ sbcglobal. net> wrote:
>   > >
>   > >
>   > > From: Bill's Personal <bill.stigall@ sbcglobal. net>
>   > > Subject: Re: [ViragoTech] pilot adjustment
>   > > To: ViragoTech@yahoogro ups.com
>   > > Date: Monday, May 10, 2010, 10:06 AM
>   > >
>   > >
>   > >
>   > > 
>   > > Mike,
>   > > You can take your time and keep tweaking it until it is perfect, (patience), or if its running good and getting good gas mileage, you can just go riding and leave it be until a problem appears and then deal with it. I go with the latter...... ... My '83 XV920 could probably be tweaked up a bit, but it runs good, gets good gas mileage, (40-45 city, 48-50 highway), so I just leave it alone and ride it. I am running a little rich, but on these bikes, rich is better than lean as fuel helps some in cooling the engine and particularly the rear cylinder.
>   > > The key, IMHO, is to keep up the regular maintenance. Follow the maintenance and service maintenance instructions in your manual. I change plugs once per season and change oil and filter every 1500 miles. I have been using Castrol GTX 20w50, but with the next change, I will switch to Mobil 1 15w50 Synthetic since it has better cooling properties. I also run a can of SeaFoam through the gas tank twice per season, (1/2 can with a full tank), to keep my carbs clean and functioning well.
>   > > So its up to you how far you want to go with tuning.
>   > >
>   > > Good and Safe Riding,
>   > > Bill
>   > >
>   > > ----- Original Message -----
>   > > From: William Hall
>   > > To: ViragoTech@yahoogro ups.com
>   > > Sent: Monday, May 10, 2010 5:07 AM
>   > > Subject: Re: [ViragoTech] pilot adjustment
>   > >
>   > >
>   > >
>   > > Ahh yes patience, sometimes thats had to come by. But I will try. Thanks, Mike
>   > >
>   > > --- On Sun, 5/9/10, Bill's Personal <bill.stigall@ sbcglobal. net> wrote:
>   > >
>   > >
>   > > From: Bill's Personal <bill.stigall@ sbcglobal. net>
>   > > Subject: Re: [ViragoTech] pilot adjustment
>   > > To: ViragoTech@yahoogro ups.com
>   > > Date: Sunday, May 9, 2010, 9:30 PM
>   > >
>   > >
>   > >
>   > > 
>   > > As you are probably aware, the plug color should be tan or both cylinders. If they are black, you will need to lean that carb out a little. Try 1/4 turn at a time and then run it again. If the plug color is white, then you will need to turn the pilot screw out and try again. The color may be different on each cylinder. On Mikuni carbs, the pilot jet handles idle and low speed, however when the engine speed picks up, the pilot jet is wide open and works in combination with the main jet to get the mixture for higher engine speeds. Therefore minor adjustments in high speed mixture can be made with the pilot screw.
>   > > Once you have both carbs running with the correct mixture, (plug color tan on both cylinders), you should be good to go. Have patience, this can take a little while to get them dialed in.
>   > >
>   > > Bill
>   > >
>   > > ----- Original Message -----
>   > > From: William Hall
>   > > To: ViragoTech@yahoogro ups.com
>   > > Sent: Sunday, May 09, 2010 5:50 PM
>   > > Subject: Re: [ViragoTech] pilot adjustment
>   > >
>   > >
>   > >
>   > > Well I set them both at 3 and no more backfire. I cleaned the plugs so after a bit of ridin I'll check them again. nstead of raising the rear of the gas tank I raised the front and it gave as much clearance as possible with the frame and wires in the way.Thanks, Mike
>   > >
>   > > --- On Sun, 5/9/10, William Hall <wmh1968@att. net> wrote:
>   > >
>   > >
>   > > From: William Hall <wmh1968@att. net>
>   > > Subject: Re: [ViragoTech] pilot adjustment
>   > > To: ViragoTech@yahoogro ups.com
>   > > Date: Sunday, May 9, 2010, 10:37 AM
>   > >
>   > >
>   > >
>   > > I've got Mikunis. I did this years ago on my 86-1100 and it never died even all the way in and I don't think it did much all the way out either but I'm gonna play with it. I forget, how do you turn the idele up on MIkunis? I had put them on my 86 when I removed my KJS single carb. Thanks, Mike
>   > >
>   > > --- On Sun, 5/9/10, Bill's Personal <bill.stigall@ sbcglobal. net> wrote:Bill,
>   > > The base setting is 2.5 turns out from a soft seat. Every bike is different, so you have to adjust each carb until you get the best idle. In is leaner; out is richer...... .... As for the procedure; it is a good general procedure with the exception of adjusting the idle speed and the jet size..... On the Virago you need to consider the sync of the carbs if you try and adjust the idle speed. Hitachi's are individually adjustable for idle speed, I am not sure about Mikuni's. If you adjust your idle up, you may have to re-sync your carbs. The turn the pilot screw all the way in, make sure you don't tighten it down tight or it will damage both the needle and the seat. On a single cylinder engine, it might die when you lean it out, but that isn't necessarily true on a twin, it should slow the idle and perhaps start hitting on one cylinder. A better read on if you are running to rich or too lean it the color of your spark plugs.
>   > > The offset screw driver is a good idea. Also a flexible screwdriver will work as well. The pilot screws are on top of the carb throat in the Mikuni carb, so you will have to raise the fuel tank or remove it and use a bottle with some fuel in it and a hose connected to the carbs. The latter is the easier way IMHO.
>   > >
>   > > Bill
>   > > ----- Original Message -----
>   > > From: William Hall
>   > > To: ViragoTech@yahoogro ups.com
>   > > Sent: Sunday, May 09, 2010 7:49 AM
>   > > Subject: [ViragoTech] pilot adjustment
>   > >
>   > >
>   > >
>   > > Here is a link and the verbage for setting the pilot. Does this sound good for our bikes? Seems like I remember the factory setting was 2.5 turns. What do you think? I got my ais removed and everything capped and now there is only a slight backfire at idle. With the Mikunis it's a pain to get at the screws. Does anyone use a 90 degree screwdriver and if so where did you get it and how much and des it reach both screw. Thanks, Mike
>   > >
>   > > This is my prefered method of finding the proper setting for the pilot screw (aka fuel screw). This method can also indicate if your pilot jet is too big or too small. Towards the bottom is an explination about the difference between fuel screws and air screws.
>   > >
>   > > You'll need to be able to access the fuel screw while the engine is running. This can be quite difficult on many carbs. FCRs have aftermarket fuel screws that are longer which helps. On a stock 400EX carb (and many others) I use a 90 degree screwdriver. I bit the bullet and bought this one from MotionPro. It works well but I'm sure there are others available. If you're lucky, your fuel screw is easily reached with a normal screw driver.
>   > >
>   > > http://www.azjetski .com/catalog/ images/03MotionP roPilotAdjustSM. gif
>   > >
>   > > OK. On to the procedure!
>   > >
>   > > 1) Warm up the engine to full operating temp.
>   > >
>   > > 2) Turn up your idle a few hundred RPM using the throttle stop screw (basically you want a fast idle). This will make it easier to hear small changes in RPM. Watch for overheating- -pointing a big shop fan at your engine will help it from getting too hot during the fast idling. The whole procedure shouldn't take too long though.
>   > >
>   > > Each time you change the screw setting 1/4 or 1/2 turn or so, wait about 5 seconds to let the idle speed normalize. It usually take the carb and engine a moment to react to the change.
>   > >
>   > > 3) Turn the fuel screw IN until the idle starts to drop and miss. The engine should die if you bottom out the screw. Your pilot jet is too big if it doesn't die when the screw is bottomed out--it should die before it gets that far in.
>   > >
>   > > 4) Then begin turning the fuel screw OUT. The idle should peak and become smooth. Keep going and look for the idle to begin to drop/miss again.
>   > >
>   > > 5) The goal is to find the setting that provides the highest and smoothest idle. If it's unclear exactly were that point is then set to the midpoint between step #3 and step #4. For example, if the idle starts to drop at 1 turn out and starts to drop at 2 1/2 turns out then 1 3/4 of a turn out should be the correct setting.
>   > >
>   > > If the peak/smoothest RPM is reached somewhere between 1-3 turns then your pilot jet is correct (the 1-3 turns applies to most carb types). If you end up less than 1 turn out then your pilot jet is too big and you need a smaller one. If you end up more than three turns out or the fuel screw seems to make little difference as you continue turning it out than you need to go up (bigger) on your pilot jet.
>   > >
>   > > To re-emphisize: If the idle never drops when you're turning the fuel screw in, you need a smaller pilot jet. If the idle never drops when you're turning the fuel screw out, you need a bigger pilot jet.
>   > >
>   > > Typical fuel screw settings are in the 1 1/2 to 2 1/2 range.
>   > >
>   > > 6) Once you've got the fuel screw set, re-adjust your throttle stop screw (idle screw) to an appropriate idle speed.
>   > >
>   > > And that's it! Your pilot circuit is now VERY close to ideal. From here you can experiment with how small adjustments affect low-end (i.e. small throttle openings) response and make adjustments for weather. The hardest part is usually gaining access to the screw while the engine is running. Also, you may really have to listen carefully to detect the rpm changes in the idle. 100 or 200 rpm differences can be tough to detect when the change happens over several seconds.http://www.exriders .com/archive/ topic/229923- 1.html
>   > >
>   >
>


Reply | Threaded
Open this post in threaded view
|  
Report Content as Inappropriate

Re: The forum is experiencing problems

Mikethegod
This post has NOT been accepted by the mailing list yet.
In reply to this post by ms8238
I have a 98  Yamaha  virago 1100 can someone please post a picture of the  we have the mixture screws are  I have my carburetor off and I'm rebuilding it I do not see the mixture screws can someone please show me or show me the place to  drill the hole in the To reveal the screws don't want to draw to my carburetor in the wrong spot don't know where the Welch plotters someone please help  
Loading...