2002 Yamaha YFM660 Grizzly factory service and repair manual, Page 239Get this manual
MIDDLE GEAR 5.Install: Universal joint
Installation steps: Install the opposite yoke into the U-jointApply wheel bearing grease to the bearingsInstall the bearing onto the yoke
CAUTION:
Check each bearingThe needles can easily fall out of their racesSlide the yoke back and forth on the bearings; the yoke will not go all the way onto bearing if needle is out of place