Cheap multi-meter from harbor freight, set meter at 20v. What is the volt reading? Argument numbers read: 12.8-12.7v is ideal static number, no key on.
12.6-12.4v is in need of a charge.
11.1v says a well charged battery is the load test number via the starter motor starting the bike.
12.8v says it has PUSH = volts, so it has reserve to recover back to its static number of 12.8v when the starter stops.
14.4v says the charging system is working. It happens that fast is 12-11-12-14 in that sequence.
12.8v says this is the recovery number when bike is running.
15+v says the voltage regulator is faulty. Cannot dump a volt.+ to ground.
Conclusion:
Just by leaving a volt meter on the battery and by watching those numbers, you can pinpoint who is the problem in the charging system of the 3 components used that makeup the charging loop.
Good vs. Bad:
12-11-12-14v = Test good at every component.
12-09-11-14v = No PUSH, (click-click) no recovery is a bad battery.
12-11-12-15+v = Voltage regulator is faulty.
12-11-12-12v = Stator output is burned out.
It's that easy to figure out if it makes any sense.
Signed,
NOLTT (no one listens to turtle)