2006-2012 Honda TRX90 TRX90EX/X Service Manual, Page 267Get this manual
ELECTRIC STARTER Check the bllshing in the motor case for wear or damageBUSHING
Turn the outer race of the bearing on the armature shaft with your fingerThe bearings shou ld turn smoothly and quietlyAlso check that the bearing inner race fits tightly on the armature shaftDo not use emery or sand paper on the commutator