One of the most over looked items on a motorcycle is the wheel bearings and bearing end play. If the wheel bearing end play is too tight, the load that is put on the bearing cages will cause...

 the bearing to over heat and seize. Too loose of an end play can cause bearing and race damage, tire wobble and premature tire wear. This problem of end play is almost a thing of the past with the introduction of sealed bearings. Although better in a lot of ways, sealed bearings also need periodic inspection and replacement.
Tapered roller bearings were used 1973 thru 1999. Distance collar length & shims determines end play. These bearings should be replaced every 10,000 miles or every spring. To properly set end play on tapered roller bearings. The bearings must be clean, (No Grease). The step washer is made to ride on the inner race of the roller bearing and the shims go between the step washer and the outer spacer. Always put the thicker shim to the step washer side.
 
 End Play Specification
1973 - 1991 - .004 in. - .018 in. End play
1992 - 1999 - .002 in. - .006 in. End play
2000 to Present - .002 in. End play

Sealed bearings have special installation and removal tools - no shims are used with these bearings. To check end play the motorcycle must be raised off the ground for the wheel being checked. Mount a magnetic base dial indicator to the brake disc with the dials contact point on the end of the axle. Turn wheel through several rotations. Then move wheel from side to side to check for lateral end play. If end play is less than the service limit, bearing passes. If endplay exceeds the service wear limit or feels rough, remove wheel and replace bearings.
Remember how much is riding on your wheel bearings, mainly you and your whole motorcycle. Preventive maintenance will keep you and your bearings rolling.