I just bought my very first bike, a 1988 250 Virago and it seems to have a charging issue. I've paid $500 to get the charging system fixed, and when it still wasn't solved, the mechanic said that it might need a new battery every year? (The one in it was just purchased in July 2015)
Does anyone else have this problem? How often do you guys replace the battery?
The Stator creates AC current that goes thru a Rectifier (filled with diodes) that changes the wave form into DC current. If just one goes bad, AC current passes into the electrical module (creating havoc) and results in your problem of boiling the battery electrolyte and internal plates until it fails.
Its very easy to check the rectifier/regulator's out put voltage for AC. It SHOULD only be DC.