Yamaha Wr 450 F Owners Manual

 
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CHASSIS/BRAKE SYSTEM AIR BLEEDING 
EC360000 
CHASSIS 
EC361012 
BRAKE SYSTEM AIR BLEEDING
WARNING
 
Bleed the brake system if: 
 
The system has been disassembled. 
 
A brake hose has been loosened or
removed. 
 
The brake fluid is very low. 
 
The brake operation is faulty.
A dangerous loss of braking performance
may occur if the brake system is not prop- 
erly bled. 
1. Remove: 
 
Master cylinder cap 
 
Diaphragm 
 
Protector (rear brake)
2. Bleed: 
 
Brake fluid 
Å 
Front...

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FRONT BRAKE ADJUSTMENT
3. Install:
Protector (rear brake)
Diaphragm
Master cylinder cap
NOTE:
If bleeding is difficult, it may be necessary to
let the brake fluid system stabilize for a few
hours. Repeat the bleeding procedure when
the tiny bubbles in the system have disap-
peared.
j. Add brake fluid to the level line on the
reservoir.
WARNING
Check the operation of the brake after
bleeding the brake system.
EC362040
FRONT BRAKE ADJUSTMENT
1. Check:
Brake lever position a 
Brake lever...

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INSP
ADJREAR BRAKE ADJUSTMENT/
FRONT BRAKE PAD INSPECTION AND REPLACEMENT
EC364002
REAR BRAKE ADJUSTMENT
1. Check:
Brake pedal height a 
Out of specification → Adjust.
Brake pedal height a:
5 mm (0.20 in)
2. Adjust:
Brake pedal height
Pedal height adjustment steps:
Loosen the locknut 1.
Turn the adjusting nut 2 until the pedal
height a is within specified height.
Tighten the locknut.
WARNING
Adjust the pedal height between the
maximum Å and the minimum ı as
shown. (In this adjustment, the...

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FRONT BRAKE PAD INSPECTION AND REPLACEMENT
Loosen the pad pin 2.
Remove the brake hose holder 3 and cal-
iper 4 from the front fork.
Remove the pad pin and brake pads 5.
Connect the transparent hose 6 to the
bleed screw 7 and place the suitable con-
tainer under its end.
Loosen the bleed screw and push the cali-
per piston in.
CAUTION:
Do not reuse the drained brake fluid.
Tighten the bleed screw.
T R..
Bleed screw:
6 Nm (0.6 m • kg, 4.3 ft • lb)
Install the brake pads 8 and pad...

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REAR BRAKE PAD INSPECTION AND REPLACEMENT
3. Inspect:
Brake fluid level
Refer to “BRAKE FLUID LEVEL
INSPECTION” section.
4. Check:
Brake lever operation
A softy or spongy feeling → Bleed
brake system.
Refer to “BRAKE SYSTEM AIR
BLEEDING” section.
Install the pad pin plug B.
T R..
Pad pin plug:
3 Nm (0.3 m • kg, 2.2 ft • lb)
EC366060
REAR BRAKE PAD INSPECTION AND 
REPLACEMENT
1. Inspect:
Brake pad thickness a 
Out of specification → Replace as a
set.
2. Replace:
Brake pad
Brake pad...

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REAR BRAKE PAD INSPECTION AND REPLACEMENT
Remove the pad pin 6 and brake pads 7.
Connect the transparent hose 8 to the
bleed screw 9 and place the suitable con-
tainer under its end.
Loosen the bleed screw and push the cali-
per piston in.
CAUTION:
Do not reuse the drained brake fluid.
Tighten the bleed screw.
T R..
Bleed screw:
6 Nm (0.6 m • kg, 4.3 ft • lb)
Install the brake pad 0 and pad pin A.
NOTE:
Install the brake pads with their projec-
tions a into the caliper recesses b....

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INSP
ADJREAR BRAKE PAD INSULATOR INSPECTION/
BRAKE FLUID LEVEL INSPECTION
3. Inspect:
Brake fluid level
Refer to “BRAKE FLUID LEVEL
INSPECTION” section.
4. Check:
Brake pedal operation
A softy or spongy feeling → Bleed
brake system.
Refer to “BRAKE SYSTEM AIR
BLEEDING” section.
EC36b000
REAR BRAKE PAD INSULATOR 
INSPECTION
1. Remove:
Brake pad
Refer to “REAR BRAKE PAD INSPEC-
TION AND REPLACEMENT” section.
2. Inspect:
Rear brake pad insulator 1 
Damage → Replace.
EC367001
BRAKE FLUID LEVEL...

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SPROCKETS INSPECTION/DRIVE CHAIN INSPECTION
EC368000
SPROCKETS INSPECTION
1. Inspect:
Sprocket teeth a 
Excessive wear → Replace.
NOTE:
Replace the drive, driven sprockets and drive
chain as a set.
DRIVE CHAIN INSPECTION
1. Remove:
Drive chain 1 
NOTE:
Remove the drive chain using a chain cutter
2.
2. Clean:
Drive chain
Brush off as much dirt as possible.
Then clean the chain using the chain
cleaner.
CAUTION:
This machine has a drive chain with small
rubber O-rings 1 between the side...

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DRIVE CHAIN INSPECTION
5. Check:
Drive chain stiffness a 
Clean and oil the chain and hold as
illustrated.
Stiff → Replace the drive chain.
6. Install:
Joint 1 
O-ring 2 
Drive chain 3 
NOTE:
When installing the drive chain, apply the lith-
ium soap base grease on the joint and O-rings.
7. Install:
Link plate 4 
NOTE:
Press the link plate onto the joint using a
chain riveter 5.
Rivet the end of the joint using a chain riv-
eter.
After riveting the joint, make sure its move-
ment...

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DRIVE CHAIN SLACK ADJUSTMENT
DRIVE CHAIN SLACK ADJUSTMENT
1. Elevate the rear wheel by placing the
suitable stand under the engine.
2. Check:
Drive chain slack a 
Above the seal guard installation bolt.
Out of specification → Adjust.
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 chain slack
with the rear wheel in this “tight chain” position.
Drive chain...