2003 YAMAHA YZ450F brake

5 - 5
CHAS

FRONT WHEEL AND REAR WHEEL
EC595000
ASSEMBLY AND INSTALLATION
Front wheel
1. Install:

Bearing (left)
1


Spacer
2


Bearing (right)
3


Oil seal
4

NOTE:


Apply the lithium soap base grease on the
bearing and oil seal lip when installing.

Use a socket that matches the outside diam-
eter of the race of the bearing.

Left side of bearing shall be installed first.

Install the oil seal with its manufacture’s
marks or numbers facing outward.
ACHTUNG:CAUTION:

Do not strike the inner race of the bearing.
Contact should be made only with the outer
race.
2. Install:
Brake disc 1
Bolt (brake disc) 2
NOTE:
Tighten the bolts in stage, using a crisscross
pattern.
New
T R..12 Nm (1.2 m · kg, 8.7 ft · lb)
3. Install:
Collar 1
NOTE:
Apply the lithium soap base grease on the oil
seal lip.
Install the collars with their projections a
facing the wheel.
4. Install:
Wheel
NOTE:
Install the brake disc 1 between the brake
pads 2 correctly.

5 - 6
CHASFRONT WHEEL AND REAR WHEEL
5. Install:
Wheel axle 1
NOTE:
Apply the lithium soap base grease on the
wheel axle.
6. Install:
Nut (wheel axle) 1
T R..105 Nm (10.5 m · kg, 75 ft · lb)
7. Tighten:
Bolt (axle holder) 1
NOTE:
Before tightening the bolt, fit the wheel axle to
the axle holder by stroking the front fork sev-
eral times with the front brake applied.
8. Install:
Brake hose 1
To brake hose holder 2.
NOTE:
Before tightening the bolt (brake hose holder),
align the top a of the brake hose neck with the
brake hose holder bottom b. Then pass the
brake hose in front of the axle boss c and fit it
into the hose groove d so that the brake hose
does not contact the nut (wheel axle).
T R..23 Nm (2.3 m · kg, 17 ft · lb)
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)

5 - 7
CHASFRONT WHEEL AND REAR WHEEL
9. Install:
Hose cover 1
Plain washer 2
Bolt [hose cover (M8)] 3
Bolt [hose cover (M6)] 4
T R..16 Nm (1.6 m · kg, 11 ft · lb)
T R..7 Nm (0.7 m · kg, 5.1 ft · lb)
Rear wheel
1. Install:
Bearing (right) 1
Circlip 2
Spacer 3
Bearing (left) 4
Oil seal 5
NOTE:
Apply the lithium soap base grease on the
bearing and oil seal lip when installing.
Install the bearing with seal facing outward.
Use a socket that matches the outside diam-
eter of the race of the bearing.
Right side of bearing shall be installed first.
Install the oil seal with its manufacture’s
marks or numbers facing outward.
ACHTUNG:CAUTION:
Do not strike the inner race of the bearing.
Contact should be made only with the outer
race.
New
New
2. Install:
Brake disc 1
Bolt (brake disc) 2
NOTE:
Tighten the bolts in stage, using a crisscross
pattern.
T R..14 Nm (1.4 m · kg, 10 ft · lb)

5 - 8
CHAS
3. Install:
Driven sprocket 1
Bolt (driven sprocket) 2
Plain washer (driven sprocket) 3
Nut (driven sprocket) 4
NOTE:
Tighten the nuts in stage, using a crisscross
pattern.
T R..42 Nm (4.2 m · kg, 30 ft · lb)
FRONT WHEEL AND REAR WHEEL
4. Install:
Collar 1
NOTE:
Apply the lithium soap base grease on the oil
seal lip.
5. Install:
Wheel
NOTE:
Install the brake disc 1 between the brake
pads 2 correctly.
6. Install:
Drive chain 1
NOTE:
Push the wheel 2 forward and install the drive
chain.
7. Install:
Chain puller (left) 1
Wheel axle 2
NOTE:
Install the chain puller (left), and insert the
wheel axle from left side.
Apply the lithium soap base grease on the
wheel axle.

5 - 10
CHASFRONT BRAKE AND REAR BRAKE
EC5A0000
FRONT BRAKE AND REAR BRAKE
EC5A8000
FRONT BRAKE
Extent of removal:1 Brake hose removal2 Caliper removal
3 Master cylinder removal
Extent of removal Order Part name Q’ty Remarks
Preparation for removalFRONT BRAKE REMOVAL
Hold the machine by placing the
suitable stand under the engine.
Drain the brake fluid.
WARNING
Support the machine securely so there is nodanger of it falling over.
Refer to “REMOVAL POINTS”.
1 Hose cover 1
2 Brake hose holder 1
3 Bolt (brake hose holder) 2 Only loosening.
4 Union bolt 2
5 Brake hose 1
6 Pad pin plug 1 Remove when loosening the pad pin.
7 Pad pin 1 Loosen when disassembling the caliper.
8 Caliper 1
9 Brake lever 1
10 Master cylinder bracket 1
11 Master cylinder 1
2
3
1
3
2

5 - 11
CHAS
EC5A8100
REAR BRAKE
Extent of removal:1 Master cylinder removal2 Brake hose removal
3 Caliper removal
Extent of removal Order Part name Q’ty Remarks
Preparation for removalREAR BRAKE REMOVAL
Hold the machine by placing the
suitable stand under the engine.
WARNING
Support the machine securely so there is nodanger of it falling over.
Rear wheel Refer to “FRONT WHEEL AND REAR
WHEEL” section.
Drain the brake fluid. Refer to “REMOVAL POINTS”.
1 Brake pedal 1
2 Master cylinder 1
3 Brake hose holder 2
4 Union bolt 2
5 Brake hose 1
6 Pad pin plug 1 Remove when loosening the pad pin.
7 Pad pin 1 Loosen when disassembling the caliper.
8Caliper
1
3
1
321
FRONT BRAKE AND REAR BRAKE

5 - 12
CHAS
EC5A8200
CALIPER DISASSEMBLY
ÅFront
ıRear
Extent of removal:1 Front caliper disassembly2 Rear caliper disassembly
Extent of removal Order Part name Q’ty Remarks
CALIPER DISASSEMBLYAB
1 Pad pin 1 1
2 Brake pad 2 2
3 Pad support 1 1
4 Caliper piston 2 1 Refer to “REMOVAL POINTS”.
5 Dust seal 2 1
Refer to “REMOVAL POINTS”.
6 Piston seal 2 1
12
FRONT BRAKE AND REAR BRAKE

5 - 13
CHASFRONT BRAKE AND REAR BRAKE
EC5A8300
MASTER CYLINDER DISASSEMBLY
ÅFront
ıRear
Extent of removal:1 Front master cylinder disassembly2 Rear master cylinder disassembly
Extent of removal Order Part name Q’ty Remarks
MASTER CYLINDER DISAS-
SEMBLY
1 Master cylinder cap 1
2 Diaphragm 1
3 Master cylinder boot 1
4 Circlip 1 Use a long nose circlip pliers.
5 Plain washer 1
6 Push rod 1
7 Master cylinder kit
1
12
12