2004 YAMAHA YZ85 warning

4 - 49
ENG
EC4M0000
ENGINE REMOVAL
5PA41490
Extent of removal Order Part name Q’ty Remarks
ENGINE REMOVAL
Preparation for removal Hold the machine by placing the
suitable stand under the frame.
WARNING
Support the machine securely so there is no
danger of it falling over.
Drain the coolant. Refer to “COOLANT REPLACEMENT”
section in the CHAPTER 3.
Seat and fuel tank Refer to “SEAT, FUEL TANK AND SIDE
COVERS” section.
Carburetor Refer to “CARBURETOR AND REED
VALVE” section.
Exhaust pipe and silencer Refer to “EXHAUST PIPE AND
SILENCER” section.
Clutch cable Disconnect at engine side.
Radiator hose 1 Disconnect at cylinder head side.
Radiator hose 2 Disconnect at water pump side.
Spark plug cap
Disconnect the CDI magneto
lead.
ENGINE REMOVAL

5 - 1
CHAS
EC500000
CHASSIS
EC590000
FRONT WHEEL AND REAR WHEEL
EC598000
FRONT WHEEL
FRONT WHEEL AND REAR WHEEL
Extent of removal:
1 Front wheel removal
2 Wheel bearing removal
3 Brake disc removal
Extent of removal Order Part name Q’ty Remarks
Preparation for removalFRONT WHEEL 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.
1 Nut (front wheel axle) 1
2 Front wheel axle 1
3 Front wheel 1
4 Collar 2
5 Oil seal 2
6 Bearing 2 Refer to “REMOVAL POINTS”.
7 Brake disc 1
2
31
3
5PA50010

5 - 2
CHAS
EC598100
REAR WHEEL
5PAR0012
Extent of removal:
1 Rear wheel removal
2 Wheel bearing removal
3 Brake disc removal
Extent of removal Order Part name Q’ty Remarks
Preparation for removalREAR WHEEL 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.
1 Nut (rear wheel axle) 1
2 Rear wheel axle 1
3 Drive chain puller 2
4 Rear wheel 1 Refer to “REMOVAL POINTS”.
5 Collar 2
6 Rear wheel sprocket 1
7 Oil seal 2
8 Circlip 1
9 Bearing 2 Refer to “REMOVAL POINTS”.
10Brake disc
1
2
31
3
FRONT WHEEL AND REAR WHEEL

5 - 4
CHAS
EC514200
Wheel axle
1. Measure:

Wheel axle bends
Out of specification → Replace.
Use the dial gauge 1.
NOTE:
The bending value is shown by one half of the
dial gauge reading.
WARNING
Do not attempt to straighten a bent axle.
Wheel axle bending limit:
0.5 mm (0.020 in)
5PA50070
Brake disc
1. Measure:

Brake disc deflection
Use the dial gauge 1.
Out of specification → Inspect wheel
runout.
If wheel runout is in good condition, replace
the brake disc.
2. Measure:

Brake disc thickness a
Out of limit → Replace.
Brake disc deflection limit:
0.15 mm (0.006 in)
Brake disc thickness:
3.0 mm (0.12 in)
: 2.5 mm (0.10 in)
5PA50080
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
5PAR0016
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 nodanger 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 - 14
CHAS
Brake caliper piston
1. Remove:

Brake caliper piston
Use compressed air and proceed carefully.
WARNING

Cover piston with rag and use extreme
caution when expelling piston from cylin-
der.

Never attempt to pry out piston.
ÈFront
ÉRear
Caliper piston removal steps:

Insert a piece of rag into the brake caliper
to lock one brake caliper.

Carefully force the piston out of the brake
caliper cylinder with compressed air.
È
5PA50330
5PA50340
Brake caliper piston seal kit
1. Remove:

Dust seal 1

Piston 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:

Brake master cylinder inner surface a
Wear/scratches → Replace master cylin-
der assembly.
Stains → Clean.
WARNING
Use only new brake fluid.
ÈFront
ÉRear
2. Inspect:

Diaphragm 1
Crack/damage → Replace.
ÈFront
ÉRear
È
É
5PA50370
È
É
5PA50380
3. Inspect: (only front brake master cylinder)

Reservoir float 1
Damage → Replace.
5PA50380
4. Inspect:

Brake master cylinder piston 1

Brake master cylinder cup 2
Wear/damage/score marks → Replace
brake master cylinder kit.
ÈFront
ÉRear
É È
5PA50390
Brake caliper
1. Inspect:

Brake caliper cylinder inner surface a
Wear/score marks → Replace brake cali-
per assembly.
ÈFront
ÉRear
È
5PA50400
É
FRONT BRAKE AND REAR BRAKE