2006-2012 Honda TRX90 TRX90EX/X Service Manual, Page 163Get this manual
ALTERNATORSTARTER CLUTCHCAM CHAIN TENSIONER Remove 'the three clutch outer mounting screws
Remove the starter clutch outer, side plate and dowel pin
DOWEL PIN
Check the starter driven sprocket for wear or dam ageInspect the starter driven sprocket boss for excessive wear or damageCheck the oil seal for wear or damage and replace it if necessary