Wow....why do you guys do it the hard way?
Take your voltmeter and put it across the battery terminals when the bike is running. If it reads 12v or less then the battery is not being charged. Not sure what the operating voltage on a bike is but I'm assuming it should be 13.8-14v, like on a car.
From my experience, a voltage regulator usually ( I said usually) allows the battery to over charge when it's faulty.
So, I'm going to take an educated guess here and say your stator is the culprit.....