brake YAMAHA YZ85 2002 Owner's Guide

5 - 7
CHAS
2. Install:
lBrake disc 1
lBolt (brake disc) 2
NOTE:
Tighten the bolts (brake disc) in stage, using a
crisscross pattern.
5PA50160
T R..12 Nm (1.2 m · kg, 8.7 ft · lb)
3. Install:
lRear wheel sprocket 1
lBolt (rear wheel sprocket) 2
lWasher (rear wheel sprocket) 3
lNut (rear wheel sprocket) 4
NOTE:
Tighten the nuts (rear wheel sprocket) in
stage, using a crisscross pattern.5PA50170
T R..42 Nm (4.2 m · kg, 30 ft · lb)
4. Install:
lCollar 1
NOTE:
Apply the lithium soap base grease on the oil
seal lip.
5PA50180
5. Install:
lWheel
NOTE:
Install the brake disc 1 between the brake
pads 2 correctly.
5PA50190
6. Install:
lDrive chain 1
NOTE:
Push the wheel 2 forward and install the drive
chain.
5PA50200
FRONT WHEEL AND REAR WHEEL

5 - 9
CHASFRONT BRAKE AND REAR BRAKE
EC5A0000
FRONT BRAKE AND REAR BRAKE
EC5A8000
FRONT BRAKE
5PA50250
Extent of removal:
1 Brake hose removal
2 Brake caliper removal
3 Brake 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.
WARNING
Support the machine securely so there is no
danger of it falling over.
Drain the brake fluid. Refer to “REMOVAL POINTS”.
1 Protector 1
2 Brake hose holder 1
3 Union bolt 2
4 Brake hose 1
5 Brake caliper support bolt 1
6 Brake caliper 1 Refer to “REMOVAL POINTS”.
7Brake lever 1
8 Brake master cylinder bracket 1
9 Brake master cylinder 1
2
3
132

5 - 10
CHAS
EC5A8100
REAR BRAKE
5PA50260
Extent of removal:
1 Brake caliper removal
2 Brake hose removal
3 Brake master cylinder 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 no
danger of it falling over.
Drain the brake fluid. Refer to “REMOVAL POINTS”.
1 Protector 1
2 Pad pin 2 Loosen when disassembling the caliper.
3 Brake caliper 1
4 Brake hose holder 2
5 Union bolt 2
6 Brake hose 1
7 Brake pedal 1
8 Reservoir tank 1
9 Reservoir hose 1
10 Brake master cylinder 1
3
1
321
FRONT BRAKE AND REAR BRAKE

5 - 11
CHAS
BRAKE CALIPER DISASSEMBLY
5PA50270
ÈFront
ÉRear
Extent of removal:
1 Front brake caliper disassembly
2 Rear brake caliper disassembly
Extent of removal Order Part name Q’ty Remarks
BRAKE CALIPER DISASSEM-
BLY
1 Brake pad 2
2 Brake caliper bracket 1
3 Brake caliper piston 2 Refer to “REMOVAL POINTS”.
4 Dust seal 2
Refer to “REMOVAL POINTS”.
5 Piston seal 2
6 Pin boot 1
7 Sleeve boot 1
8 Pad pin 2
9 Brake pad 2
0 Brake caliper piston 1 Refer to “REMOVAL POINTS”.
A Dust seal 1
Refer to “REMOVAL POINTS”.
B Piston seal
1
2
1
FRONT BRAKE AND REAR BRAKE

5 - 12
CHAS
BRAKE MASTER CYLINDER DISASSEMBLY
5PA50280
ÈFront
ÉRear
Extent of removal:
1 Front brake master cylinder disassembly
2 Rear brake master cylinder disassembly
Extent of removal Order Part name Q’ty Remarks
BRAKE MASTER CYLINDER
DISASSEMBLY
1 Brake master cylinder cap 1
2 Diaphragm 1
3 Brake master cylinder boot 1
4 Circlip 1 Use a long nose circlip pliers.
5 Washer 1
6 Push rod 1
7 Brake master cylinder kit
1
12
21
FRONT BRAKE AND REAR BRAKE

5 - 13
CHAS
EC5A3000
REMOVAL POINTS
Brake fluid
1. Remove:
[Front]
lBrake master cylinder cap 1
[Rear]
lReservoir tank cap 1
NOTE:
Do not remove the diaphragm.
ÈFront
ÉRear
È
5PA50290
€
É
5PA50300
2. Connect the transparent hose 2 to the
bleed screw 1 and place a suitable con-
tainer under its end.
ÈFront
ÉRear
3. Loosen the bleed screw and drain the
brake fluid while pulling the lever in or
pushing down on the pedal.
CAUTION:
lDo not reuse the drained brake fluid.
lBrake fluid may erode painted surfaces or
plastic parts. Always clean up spilled
fluid immediately.
€
ÈÉ
5PA50310
Front brake caliper
1. Remove:
lBrake caliper 1
NOTE:
Turn the brake caliper counterclockwise and
pull out it from the guide pin 2 on the brake
caliper bracket.
€
5PA50320
FRONT BRAKE AND REAR BRAKE

5 - 14
CHAS
Brake caliper piston
1. Remove:
lBrake caliper piston
Use compressed air and proceed carefully.
WARNING
lCover piston with rag and use extreme
caution when expelling piston from cylin-
der.
lNever attempt to pry out piston.
ÈFront
ÉRear
Caliper piston removal steps:
lInsert a piece of rag into the brake caliper
to lock one brake caliper.
lCarefully force the piston out of the brake
caliper cylinder with compressed air.
È
5PA50330
€
5PA50340
Brake caliper piston seal kit
1. Remove:
lDust seal 1
lPiston seal 2
NOTE:
Remove the piston seals and dust seals by
pushing them with a finger.
CAUTION:
Never attempt to pry out piston seals and
dust seals.
WARNING
Replace the piston seals and dust seals
whenever a caliper is disassembled.
ÈFront
ÉRear
È
5PA50350
€
É
5PA50360
É
FRONT BRAKE AND REAR BRAKE

5 - 15
CHAS
EC5A4000
INSPECTION
Brake master cylinder
1. Inspect:
lBrake master cylinder inner surface a
Wear/scratches ® Replace master cylin-
der assembly.
Stains ® Clean.
WARNING
Use only new brake fluid.
ÈFront
ÉRear
2. Inspect:
lDiaphragm 1
Crack/damage ® Replace.
ÈFront
ÉRear
€ È
É
5PA50370
€
È
É
5PA50380
3. Inspect:
lBrake master cylinder piston 1
lBrake master cylinder cup 2
Wear/damage/score marks ® Replace
brake master cylinder kit.
ÈFront
ÉRear
€
É È
5PA50390
Brake caliper
1. Inspect:
lBrake caliper cylinder inner surface a
Wear/score marks ® Replace brake cali-
per assembly.
ÈFront
ÉRear
€
È
5PA50400
É
2. Inspect:
lBrake caliper piston 1
Wear/score marks ® Replace brake cali-
per piston assembly.
WARNING
Replace the piston seals and dust seals 2
whenever a caliper is disassembled.
5PA50410
FRONT BRAKE AND REAR BRAKE

5 - 16
CHAS
3. Inspect: (only front brake caliper)
lBrake caliper bracket 1
Cranks/damage ® Replace the brake cali-
per assembly.
lGuide pin 2
Rust/damage ® Replace the brake caliper
assembly.
lSleeve boot 3
lPin boot 4
Wear/damage ® Replace.5PA50420
4. Inspect: (only front brake caliper)
lBrake caliper support bolt 1
Scorches/rust/damage ® Replace.
5PA50430
EC534301
Brake hose
1. Inspect:
lBrake hose 1
Crack/damage ® Replace.
5PA50440
EC5A5000
ASSEMBLY AND INSTALLATION
WARNING
lAll internal parts should be cleaned in
new brake fluid only.
lInternal parts should be lubricated with
brake fluid when installed.
lReplace the piston seals and dust seals
whenever a caliper is disassembled.
Brake caliper piston
1. Clean:
lBrake caliper
lPiston seal
lDust seal
lBrake caliper piston
Clean them with brake fluid.
FRONT BRAKE AND REAR BRAKE

5 - 17
CHAS
2. Install:
lPiston seal 1
lDust seal 2
WARNING
Always use new piston seals and dust
seals.
NOTE:
Fit the piston seals and dust seals onto the slot
on brake caliper correctly.
ÈFront
ÉRear
È
5PA50450
É
5PA50460
3. Install:
lBrake caliper piston 1
NOTE:
Apply the brake fluid on the brake caliper pis-
ton wall.
CAUTION:
lFor the front brake caliper, install the pis-
ton with its shallow depressed side
a
facing the caliper. For the rear brake cali-
per, install the piston with its depressed
side
b facing the brake caliper.
lNever force to insert.
ÈFront
ÉRear
È
5PA50470
É
5PA50480
Front brake caliper
1. Install:
lSleeve boot 1
On brake caliper bracket 2.
5PA50490
FRONT BRAKE AND REAR BRAKE