My bike will cut out every time when I'm at full throttle and start to over rev. When it reaches max rpm's it cuts out continuously for about half a second at a time. I've tried both a richer main jet and leaner and it didn't seem to make a difference. The spark plug looks fine (light brown) and I run ethanol free 93, 40:1. I've tried straight AVgas 40:1 and it didn't make a difference.I don't think its jetting, fuel or carburetor related. It seems to cut out more frequently when I ride it hard and it gets really hot. It runs perfect up until it reaches max rpms and then it starts sputtering. Does anyone have any ideas?