1998-2001 Honda Fourtrax Foreman TRX450S, TRX450ES Factory Service Manual, Page 269Get this manual
BRAKE SYSTEM Measure the brake drum LDSERVICE UMrr: 161
mm (6.34 inl
Remove the following:Wheel huba'nd O-ringDlu stseal For front brake waterproof seal inspectionreplacementsee pag'e 14 '1 ,
Measure the brake .ining thicknessI
SERVlCE LIMIT: 2.0 mm (0.08 inl For brake panel inspectionsee page 14 10