Get a USED stock stator and put it on. This does not sound like a jetting issue... WHen a bike heats up, electrical problems arise.
Are you losing any coolant?
Pull your flywheel off and shake it like a maraca....you should hear NOTHING. If you hear something jingling around inside the flywheel, replace it.
After two stock output Ricky Stator stators on my drag bike (read, no rain, mud, etc.) in two years, both dying just before the year warranty was up, I threw the last one in the trash. Didn't even bother calling for a warranty or refund. That fed up.
I got a rusty, old, beat up looking stocker that is running like a champ on there...
And as said, check your flywheel gap. .015 to .018 is where I like to run mine. Also check wires on the bike for fraying or bare ground out wires.... Bypass kill switches if you can, too....