2008-2010 Kawasaki KFX450R Factory Service Manual, Page 279Get this manual
CRANKSHAFTTRANSMISSION 9-31 BearingsOil Seals
Check the needle bearingnormally wear very little, The rollers in needle bearing
and wear is difficult to measureInstead of measuring, inspect the bearing for abrasion, color change, or other damageIf there is any doubt as to the condition of needle bearing, replace it