2001 Yamaha YFM660 Raptor Factory Service Manual, Page 324Get this manual
FAULTY GEAR SHIFTING CLUTCH SLIPPINGDRAGGING FAULTY GEAR SHIFTING HARD SHIFTING Refer to "CLUTCH DRAGGING"
TRBL SHTG
SHIFT PEDAL DOES NOT MOVE Shift shaft Bent shift shaft Shift drum and shift fork Groove jammed with impurities Seized shift fork Bent shift fork guide bar
Transmission Seized transmission gear Jammed impurities Incorrectly assembled transmission Shift guide Broken shift guide
JUMP-OUT GEAR Shift shaft Improperly adjusted shift lever position Improperly returned stopper lever Shift fork Worn shift fork