V-strom (1000) not holding a charge
So here's the deal- When I ride the bike, after a stop or two, I notice the engine is turning over slower than I'd like...and I know that if it didn't start, I'd only have like 1 more try before it wouldn't turn over anymore. Lately, after 2 or 3 stops, I can't re-start the engine, and must bump start it (not a whole lot of fun on a liter bike).
The battery is older, but seems just fine when charged with a home charger. In fact, I can put it on 2A for 30 minutes, and it will hold at 12.5v and start the motor after sitting for 1 week or more. So, my inclination is that the battery isn't the culprit here (but maybe I'm wrong).
The charging system- after I bump start it, and get it home and charge it back up with a battery charger....I have tested the charging system's output by checking the voltage, while running, at the battery. What I see is usually this-
2,000-5,000 rpm- 15.1V to 15.2V (though I've seen as high as 15.9).....then settles down to 15.0
So, I'm confused because though I see there is possibly a problem with the regulator/rectifier (shouldn't be above 14.6).....why would this cause a DIScharging battery?? I can see how excess voltage could ruin a battery...but why the discharge, only to accept a charge and act perfectly normal later? Seems to me that a 15V charging system would charge the battery perfectly fine, but eventually destroy it (maybe). Why is it just discharging....and working fine once recharged? I'm tempted to start with the easy/cheap stuff (battery) and move up to R/R....then to the stator if necessary. Anyone have any idea what I may be looking at?
Yea...I'm gonna need you to move a little to the left.....yea