Battery won't stay charged
Hello, I am new to this forum and this is my first post. I have a 1985 VN700 that runs great, however the battery refuses to stay charged after a couple rides. I know the battery is fully charged, because I charge it on a trickle charger and test it with a multimeter. When fully charged, the voltage reads around 12.5 volts.
I tested to see if the stator sends any power to the battery yesterday, and the voltage jumps up slightly (between .3-.5 volts) when I pull back on the throttle. I went for a 60 mile ride and it had no problems. I got back, shut it off, and ten minutes later tried to start it again to get it into the garage, and the starter wouldn't even turn over. This has happened many times over the past few months, and I have to take the battery out and recharge it inside. A couple of times, the bike died on me while riding also, which is initially what got me to believe that the stator might be bad (and knowing that stators for these kinds of bikes tend to go bad), but obviously it sends some power to the battery. My next thing to check is going to be the voltage regulator, I read that also can go bad. Could the stator still work partially (showing a spike in voltage), but just not keep up with the electrical demands of the bike? Can you guys think of anything else that I could check that might be the culprit?
Thank you very much