1985-1986 Honda Fourtrax 125 TRX125 Shop Manual, Page 125Get this manual
RECOIL STARTER ALTERNATOR CAM CHAIN TENSIONER
INSPECTION
Measure the 1.0and 0.0of the drive sprocket
bush ingsSERVICE LIMITS ;
0 .0 21.90 mm fO.B62 inl 1.0: 19.94 mm 10.185 in)
For drive sprocket inspeciton, see page 314SPROCKET
DRIVE SPROCKET INSTALLATION