A few months ago I was having battery issues - the battery wouldn't hold a charge. Since the bike is an 08 (sportster 1200) I figured replacing the battery was in order.
I took it on several rides around 50 miles each and noticed that the new battery was not turning over as quickly as I would have expected. I bought a charger and hooked it up overnight and it started right up. I took it out for a longer ride, around 100 miles, and it died about 95 mile in. Towed it home looked at the battery and it was toast - it molded to the shape of the battery compartment. The bike also had a strong smell coming from the side that the oil tank is on.
Brought it to the dealer and they said it was a bad voltage regulator, so now I have a new battery (again) and a new voltage regulator. It seemed ok until about a week ago, I turned the throttle in second gear and the battery and engine light went on and stayed on.

I got a multimeter and tested the stator high 30's to low 40's for volts at idle and 51 when I bring it up to around 2K rpm.

I think that the stator might be the issue. Thoughts?

 

If you haven't read them yet, look through the two Stickies at the top of this Tech Electrical section, on checking your charging system. They should help you confirm which unit has failed.

 

It sounds like the stator isn't charging the new battery. It will run off of battery juice until the battery has no more. When you replace the stator it should come with a new voltage regulator. Please read the sticky it WILL help you figure this out.