1998-2001 Honda Fourtrax Foreman TRX450S, TRX450ES Factory Service Manual, Page 303Get this manual
FRONT DRIVING MECHANISM PiNION Measure the pinion gear I.Dand pin ion s11aft O.DSERVICiE LIMITS: PIINION GEAR to 1205 mm (0.414 in) PINIONSHAfTO.D 11.7S lm (0.463 Ifll Check the side washer for wea'r dama.ge
DlFFER.ENnAt HOUSING Check the slots fo ea Or damage
DI FFER ENTIAL HOUSI'NG