2002 Yamaha YFM660 Grizzly factory service and repair manual, Page 403Get this manual
FAULTY DRIVE TRAIN FAULTY DRIVE TRAIN The following conditions may indicate damaged shaft drive components: Symptoms 1.A pronounced hesitation or "jerky" movement during acceleration, deceleration, or sustained speed(This must not be confused with engine surging or transmission characteristics 2.A "rolling rumble" noticeable at low speed; high-pitched whine; "clunk" from shaft drive component or area3.A locked-up condition of the shaft drive mechanism, no power transmitted from the engine to the front andor rear wheels