Weird starting issue on old interceptor

Hey everyone, looking for some help. I have an 83 vf750f that is giving me some grief. This bike will start up everytime when it's cold. No issues. It will run great while I'm riding. But, after an hour of so of riding, I sometimes stop for a coffee, or to fuel up, ect...and when I try to start the bike up again, she doesn't want to go. Battery cranks over a few times, but engine doesn't fire up, and before very long (30 seconds?) the battery sounds as if it's dying. At this point I walk away and come back in 20-30minutes, and the bike will start again fairly easily.

I suspected maybe a charging issue. It's a brand new battery, but I tested it anyway. Good voltage and when bike is running, the battery is getting a charge. (Round 14.5v)
I tested the stator. About 0.4ohms between leads, and 0 between leads to ground. With bike running, leads are reading around 45v AC when rev'ed to 4500RPM

so it doesn't look like a charging issue. I had read somewhere that it could be gas boiling over in the float bowls. Anybody hear of that? Could that be my issue?

Any help would be great. Thanks.

 

Check all your chassis ground points--you may have corrosion around a terminal lug, or a loose connection, that results in a high-resistance junction that will become even higher when the temperature is up. When it cools back down the resistance lowers. Start at the battery negative terminal and trace the wire to the engine/chassis and clean all the connections. Look for corrosion around the starter motor bolts. Old motorsickles take extra careful inspection to find problems...