So as i have nothing to do at home right now I rebuilt my Kawasaki FD620D Engine. Runs like a champ now, idling, etc. Went for a ride to see how it did top end and it started out fine but then seemed to lose power. Stopped, put in neutral, revved the engine and plenty of consistent power. Clutch on transmission not hot at all, it was recently replaced. New Belt. The Primary Clutch on engine was very hot though. the inside portion which is fixed. The outside portion seems to come in and out just fine depending on engine RPM. How do you diagnose a bad primary clutch? I took it completely apart, cleaned everything and dry lubed everything per direction on another forum. $600 for a new clutch is pretty steep, especially if that is not the issue. Suggestions?