posting for a buddy of mine, he has a low hour 08 yz450f, we were riding and all of a sudden the clutch would not disengage and he was stalling the bike. the bike has a rekluse zstart pro clutch so first thought was that. he pulled it apart and put in the factory clutch and it still does it. it just wont disengage. any common issues that you guys know of or any idea? the local dealer told him $3000 for a trans rebuild but they havent even seen the bike. do you have to split cases to rebuild trans?