Yamaha WR250F Manuel D'atelier page 238

DRIVE CHAIN SLACK ADJUSTMENT
3 - 35
EC36A060
DRIVE CHAIN SLACK ADJUSTMENT
1. Elevate the rear wheel by placing the
suitable stand under the engine.
2. Check:
Drive chain slack a
G
Above the seal guard installation bolt.
Out of specification → Adjust.
Drive chain slack:
40 ~ 50 mm (1.6 ~ 2.0 in)
NOTE:
Before checking and/or adjusting, rotate the
rear wheel through several revolutions and
check the slack several times to find the tight-
est point. Check and/or adjust the drive chain
slack with the rear wheel in this "tight chain"
position.
3. Adjust:
Drive chain slack
G
Drive chain slack adjustment steps:
Loosen the axle nut 1 and locknuts 2.
G
Adjust the drive chain slack by turning the
G
adjusters 3.
To tighten → Turn the adjuster 3 coun-
terclockwise.
To loosen → Turn the adjuster 3 clock-
wise and push wheel forward.
Turn each adjuster exactly the same
G
amount to maintain correct axle alignment.
(There are marks a on each side of the
drive chain puller alignment.)
NOTE:
Turn the adjuster so that the drive chain is in
line with the sprocket, as viewed from the rear.
CAUTION:
Too small drive chain slack will overload
the engine and other vital parts; keep the
slack within the specified limits.
Tighten the axle nut while pushing down
G
the drive chain.
Axle nut:
125 Nm (12.5 m • kg, 90 ft • lb)
Tighten the locknuts.
G
INSP
ADJ