Adjusting The Drive Chain Slack; Checking The Front Fork; Cleaning The Front Fork Oil Seal And Dust Seal - Yamaha WR450F(Y) 2009 Owner's Service Manual

6. Install:
• Chain joint "1"
• O-ring "2"
• Drive chain "3"
• Link plate "4"
When installing the drive chain, apply
the lithium soap base grease on the
chain joint and O-rings.
7. Install:
• Link plate
• Press the link plate onto the chain
joint using a drive chain riveter "5".
• Rivet the end of the chain joint us-
ing a drive chain riveter.
• After riveting the chain joint, make
sure its movement is smooth.
8. Lubricate:
• Drive chain
Drive chain lubricant:
SAE 10W-30 motor oil
or suitable chain lubri-
cants
ADJUSTING THE DRIVE CHAIN
SLACK
1. Elevate the rear wheel by placing
the suitable stand under the en-
gine.
2. Check:
• Drive chain slack "a"
Above the seal guard installation
bolt.
Out of specification → Adjust.
Drive chain slack:
48–58 mm (1.9–2.3 in)
Before checking and/or adjusting, ro-
tate the rear wheel through several
revolutions and check the slack sev-
eral times to find the tightest point.
Check and/or adjust the drive chain
slack with the rear wheel in this "tight
chain" position.
3. Adjust:
• Drive chain slack
Drive chain slack adjustment
steps:
a. Loosen the axle nut "1" and lock-
nuts "2".
b. Adjust the drive chain slack by
turning the adjusters "3".
To tighten→Turn the adjuster "3"
counterclockwise.
To loosen→Turn the adjuster "3"
clockwise and push wheel for-
ward.
c. Turn each adjuster exactly the
same amount to maintain correct
axle alignment. (There are marks
"a" on each side of the drive chain
puller alignment.) NOTICE: Im-
proper drive chain slack will
overload the engine as well as
other vital parts of the motorcy-
cle and can lead to chain slip-
page or breakage. To prevent
this from occurring, keep the
drive chain slack within the
specified limits.
Turn the adjuster so that the drive
chain is in line with the sprocket, as
viewed from the rear.
3-23
CHASSIS
d. Tighten the axle nut while pushing
down the drive chain.
Axle nut:
125 Nm (12.5 m•kg, 90
ft•lb)
e. Tighten the locknuts.
Locknut:
19 Nm (1.9 m•kg, 13
ft•lb)

CHECKING THE FRONT FORK

1. Inspect:
• Front fork smooth action
Operate the front brake and
stroke the front fork.
Unsmooth action/oil leakage →
Repair or replace.
CLEANING THE FRONT FORK OIL
SEAL AND DUST SEAL
1. Remove:
• Protector
• Dust seal "1"
Use a thin screw driver, and be care-
ful not to damage the inner fork tube
and dust seal.
2. Clean:
• Dust seal "a"
• Oil seal "b"
• Clean the dust seal and oil seal af-
ter every run.
• Apply the lithium soap base grease
on the inner tube.