Yamaha YZ450FX 2023, Owner'S Manual

Page: 70 / 164

CHASSIS
3-22
j. Pour brake fluid to the reservoir up to the
specified level.
Refer to “CHECKING THE BRAKE FLUID
LEVEL” on page 3-19.
WARNING
EWA13110
After bleeding the hydraulic brake system,
check the brake operation.
EAM30481
DRIVE CHAIN SLACK
NOTICE
ECA13550
A drive chain that is too tight will overload
the engine and other vital parts, and one that
is too loose can skip and damage the swing-
arm or cause an accident. Therefore, keep
the drive chain slack within the specified lim-
its.
Checking the drive chain slack
1. Use a maintenance stand to raise the rear
wheel off the ground.
WARNING
EWA13120
Securely support the vehicle so that there is
no danger of it falling over.
2. Shift the transmission into the neutral posi-
tion.
3. Pull the drive chain up above the drive chain
guide installation bolt with a force of about 50
N (5.0 kgf, 37 lbf).
4. Check:
• Drive chain slack “a”
Out of specification

Regulate.
TIP
Measure drive chain slack between the drive
chain guide and the bottom of the chain as
shown.
Adjusting the drive chain slack
WARNING
EWA13120
Securely support the vehicle so that there is
no danger of it falling over.
1. Adjust:
•
Drive chain slack
a. Loosen the wheel axle nut “1”.
b. Loosen both locknuts “2”.
c. Turn the adjusting bolt “3” until the speci-
fied drive chain slack is obtained.
TIP
•
To maintain the proper wheel alignment, adjust
both sides evenly.
•
Push the rear wheel forward to make sure that
there is no clearance between the swingarm
end plates and the ends of the swingarm.
d. Tighten the wheel axle nut.
e. Tighten the drive chain puller locknut.
EAM30251
LUBRICATING THE DRIVE CHAIN
The drive chain consists of many interacting
parts. If the drive chain is not maintained proper-
ly, it will wear out quickly. Therefore, the drive
chain should be serviced, especially when the
vehicle is used in dusty areas.
This vehicle has a drive chain with small rubber
O-rings between each side plate. Steam clean-
ing, high-pressure washing, certain solvents,
and the use of a coarse brush can damage
these O-rings. Therefore, use only kerosene to
Bleed screw
5 N·m (0.5 kgf·m, 3.7 lb·ft)
T
R
.
.
a a
Drive chain slack (Maintenance
Stand)
50.0–60.0 mm (1.97–2.36 in)
Wheel axle nut
125 N·m (12.5 kgf·m, 92 lb·ft)
Drive chain puller locknut
21 N·m (2.1 kgf·m, 15 lb·ft)
1
3 2
T
R
.
.
T
R
.
.