2001 YAMAHA YZ426F brake

3 - 26
INSP
ADJREAR BRAKE ADJUSTMENT/
FRONT BRAKE PAD INSPECTION AND REPLACEMENT
EC364002
REAR BRAKE ADJUSTMENT
1. Check:
lBrake pedal height a
Out of specification ® Adjust.
Brake pedal height a:
5 mm (0.20 in)
2. Adjust:
lBrake pedal height
Pedal height adjustment steps:
lLoosen the locknut 1.
lTurn the adjusting nut 2 until the pedal
height a is within specified height.
lTighten the locknut.
WARNING
lAdjust the pedal height between the
maximum and the minimum õ as
shown. (In this adjustment the bolt 3
end b should protrude out of the lower
adjusting nut 4 but not be less than
2 mm (0.08 in) c away from the brake
pedal 5).
lAfter the pedal height adjustment, make
sure that the rear brake does not drag.

õ
EC365080
FRONT BRAKE PAD INSPECTION AND
REPLACEMENT
1. Inspect:
lBrake pad thickness a
Out of specification ® Replace as a
set.
2. Replace:
lBrake pad
Brake pad thickness a:
Standard
4.4 mm (0.17 in) 1.0 mm (0.04 in)
Brake pad replacement steps:
lRemove the pad pin plug 1.

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INSP
ADJ
FRONT BRAKE PAD INSPECTION AND REPLACEMENT
lLoosen the pad pin 2.
lRemove the brake hose holder 3 and cal-
iper 4 from the front fork.
lRemove the pad pin and brake pads 5.
lConnect the transparent hose 6 to the
bleed screw 7 and place the suitable con-
tainer under its end.
lLoosen the bleed screw and push the cali-
per piston in.
CAUTION:
Do not reuse the drained brake fluid.
lTighten the bleed screw.
T R..
Bleed screw:
6 Nm (0.6 m • kg, 4.3 ft • lb)
lInstall the brake pads 8 and pad pin.
NOTE:
lInstall the brake pads with their projec-
tions a into the caliper recesses b.
lTemporarily tighten the pad pin at this
point.
lInstall the brake hose holder 9 and cali-
per 0 and tighten the pad pin A.
NOTE:
Fit the brake hose holder cut c over the
projection d on the front fork and clamp the
brake hose.
T R..
Bolt (caliper):
23 Nm (2.3 m • kg, 17 ft • lb)
Pad pin:
18 Nm (1.8 m • kg, 13 ft • lb)

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INSP
ADJ
REAR BRAKE PAD INSPECTION AND REPLACEMENT
3. Inspect:
lBrake fluid level
Refer to “BRAKE FLUID LEVEL
INSPECTION” section.
4. Check:
lBrake lever operation
A softy or spongy feeling ® Bleed
brake system.
Refer to “BRAKE SYSTEM AIR
BLEEDING” section.
lInstall 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:
lBrake pad thickness a
Out of specification ® Replace as a
set.
2. Replace:
lBrake pad
Brake pad thickness a:
Standard
6.4 mm (0.25 in) 1.0 mm (0.04 in)
Brake pad replacement steps:
lRemove the protector 1 and pad pin plug
2.
lLoosen the pad pin 3.
lRemove the rear wheel 4 and caliper 5.
Refer to “FRONT WHEEL AND REAR
WHEEL” section in the CHAPTER 5.

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INSP
ADJ
REAR BRAKE PAD INSPECTION AND REPLACEMENT
lRemove the pad pin 6 and brake pads 7.
lConnect the transparent hose 8 to the
bleed screw 9 and place the suitable con-
tainer under its end.
lLoosen the bleed screw and push the cali-
per piston in.
CAUTION:
Do not reuse the drained brake fluid.
lTighten the bleed screw.
T R..
Bleed screw:
6 Nm (0.6 m • kg, 4.3 ft • lb)
lInstall the brake pad 0 and pad pin A.
NOTE:
lInstall the brake pads with their projec-
tions a into the caliper recesses b.
lTemporarily tighten the pad pin at this
point.
lInstall the caliper B and rear wheel C.
Refer to “FRONT WHEEL AND REAR
WHEEL” section in the CHAPTER 5.
lTighten the pad pin D.
T R..
Pad pin:
18 Nm (1.8 m • kg, 13 ft • lb)
lInstall the pad pin plug E and protector F.
T R..
Pad pin plug:
3 Nm (0.3 m • kg, 2.2 ft • lb)
Bolt (protector):
7 Nm (0.7 m • kg, 5.1 ft • lb)

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INSP
ADJREAR BRAKE PAD INSULATOR INSPECTION/
BRAKE FLUID LEVEL INSPECTION
3. Inspect:
lBrake fluid level
Refer to “BRAKE FLUID LEVEL
INSPECTION” section.
4. Check:
lBrake 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:
lBrake pad
Refer to “REAR BRAKE PAD INSPEC-
TION AND REPLACEMENT” section.
2. Inspect:
lRear brake pad insulator 1
Damage ® Replace.
EC367001
BRAKE FLUID LEVEL INSPECTION
1. Place the master cylinder so that its top is
in a horizontal position.
2. Inspect:
lBrake fluid level
Fluid at lower level ® Fill up.
aLower level
Front
õRear
WARNING
lUse only designated quality brake fluid to
avoid poor brake performance.
lRefill with same type and brand of brake
fluid; mixing fluids could result in poor
brake performance.
lBe sure that water or other contaminants
do not enter master cylinder when refill-
ing.
lClean up spilled fluid immediately to
avoid erosion of painted surfaces or plas-
tic parts.
Recommended brake fluid:
DOT #4

õ

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INSP
ADJ
FRONT FORK INSPECTION
3. Adjust:
lDrive chain slack
Drive chain slack adjustment steps:
lLoosen the axle nut 1 and locknuts 2.
lAdjust chain slack by turning the adjusters
3.
To tighten ® Turn adjuster 3 counter-
clockwise.
To loosen ® Turn adjuster 3 clockwise
and push wheel forward.
lTurn each adjuster exactly the same
amount to maintain correct axle alignment.
(There are marks a on each side of chain
puller alignment.)
NOTE:
Turn the adjuster so that the chain is in line
with the sprocket, as viewed from the rear.
CAUTION:
Too small chain slack will overload the
engine and other vital parts; keep the
slack within the specified limits.
lTighten the axle nut while pushing down
the drive chain.
T R..
Axle nut:
125 Nm (12.5 m • kg, 90 ft • lb)
lTighten the locknuts.
EC36C000
FRONT FORK INSPECTION
1. Inspect:
lFront fork smooth action
Operate the front brake and stroke the
front fork.
Unsmooth action/oil leakage ® Repair
or replace.

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INSP
ADJ
LUBRICATION
LUBRICATION
To ensure smooth operation of all compo-
nents, lubricate your machine during setup,
after break-in, and after every race.
1All control cable
2Clutch lever pivot
3Shift pedal pivot
4Footrest pivot
5Throttle-to-handlebar contact
6Drive chain
7Tube guide cable winding portion
8Throttle cable end
9Clutch cable end
0Decompression cable endUse Yamaha cable lube or equivalent on these
areas.
õUse SAE 10W-30 motor oil or suitable chain
lubricants.
‚Lubricate the following areas with high quality,
lightweight lithium-soap base grease.
CAUTION:
Wipe off any excess grease, and avoid get-
ting grease on the brake discs.
AAA
AAB
CC

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ENG

CLUTCH
CLUTCH
CLUTCH
Extent of removal:
1
Push rod and push lever removal
2
Push pod 1 disassembly
3
Friction plate and clutch plate removal
4
Clutch housing removal
Extent of removal Order Part name Q’ty Remarks
CLUTCH REMOVAL
Preparation for removal Drain the engine oil. Refer to “ENGINE OIL REPLACEMENT”
section in the CHAPTER 3.
Brake pedal Refer to “ENGINE REMOVAL” section.
Clutch cable Disconnect at engine side.
1 Clutch cover 1
2 Gasket 1
3 Dowel pin 2
4 Clutch spring 6
5 Pressure plate 1
6 Push rod 1 1
7 Circlip 1
8 Plain washer 1
9 Bearing 1
10 Ball 1
11Push rod 2
1
41
2
3
1