1998-2001 Yamaha YFM600FHM Grizzly Factory Service Manual, Page 255Get this manual
REAR AXLEFINAL DRIVE GEAR AND DRIVE SHAFT
Ring gear stopper clearance adjustment 1.Remove: Ring gear D Ring gear stopper Shim(s)
Bearing housing [AJ Left-hand threads
2.Select: Suitable shim(s) Shim Thickness (mm) 0.15 0.20