Yamaha YZ125(P)/LC Owner's Service Manual page 378

FRONT WHEEL AND REAR WHEEL
8. Install:
9
Chain puller (right) 1
9
Plain washer 2
9
Nut (wheel axle) 3
NOTE:
Temporarily tighten the nut (wheel axle) at this
point.
9. Adjust:
9
Drive chain slack a
Drive chain slack :
40~50 mm (1.6~2.0 in)
Refer to "DRIVE CHAIN SLACK ADJUSTMENT"
section in the CHAPTER 3.
10. Tighten:
9
Nut (wheel axle) 1
9
Locknut 2
5-9
CHAS
125 Nm (12.5 m•kg, 90 ft•lb)