2003 YAMAHA YZ85 clutch

SPEC
2 - 11
MAINTENANCE SPECIFICATIONS
Wheel:
Front wheel type Spoke wheel ----
Rear wheel type Spoke wheel ----
Front rim size/material 19 × 1.40/Aluminum ----
Rear rim size/material 16 × 1.85/Aluminum ----
Rim runout limit:
Radial ---- 2.0 mm (0.08 in)
Lateral ---- 2.0 mm (0.08 in)
Drive chain:
Type/manufacturer DID428DS/DAIDO ----
Number of links 123 links + joint ----
Chain slack 35 ~ 45 mm (1.4 ~ 1.8 in) ----
Chain length (10 links) ---- 122.1 mm (4.81 in)
Front disc brake:
Disc outside dia. × Thickness 220 × 3.0 mm (8.66 × 0.12 in) 220 × 2.5 mm
(8.66 × 0.10 in)
Deflection limit ---- 0.15 mm (0.006 in)
Pad thickness 4.0 mm (0.16 in) 0.8 mm (0.03 in)
Master cylinder inside dia. 11.0 mm (0.433 in) ----
Caliper cylinder inside dia. 22.22 mm (0.875 in) × 2 ----
Brake fluid type DOT #4 ----
Rear disc brake:
Disc outside dia. × Thickness 190 × 3.0 mm (7.84 × 0.12 in) 190 × 2.5 mm
(7.84 × 0.12 in)
Deflection limit ---- 0.15 mm (0.006 in)
Pad thickness 3.7 mm (0.15 in) 1.0 mm (0.04 in)
Master cylinder inside dia. 12.7 mm (0.500 in) ----
Caliper cylinder inside dia. 27.0 mm (1.063 in) × 1 ----
Brake fluid type DOT #4 ----
Brake lever and brake pedal:
Brake lever position 95 mm (3.74 in) ----
Brake pedal height
(vertical height above footrest top)4 ~ 10 mm (0.16 ~ 0.39 in) ----
Clutch lever free play (lever end) 10 ~ 15 mm (0.39 ~ 0.59 in) ----
Throttle grip free play 3 ~ 5 mm (0.12 ~ 0.20 in) ----Item Standard Limit

SPEC
2 - 12
MAINTENANCE SPECIFICATIONS
NOTE:
1. First, tighten the steering nut approximately 38 Nm (3.8 m  kg, 27 ft  lb) by using the steering
nut wrench, then loosen the steering nut one turn.
2. Retighten the steering nut 4 Nm (0.4 m  kg, 2.9 ft  lb). Part to be tightened Thread size Q’tyTightening torque
Nm m·kg ft·lb
Upper bracket and outer tube M8 × 1.25 2 22 2.2 16
Lower bracket and outer tube M8 × 1.25 4 20 2.0 14
Upper bracket and steering stem M22 × 1.0 1 125 12.5 90
Handlebar holder and upper bracket M8 × 1.25 4 27 2.7 19
Steering stem and steering ring nut M25 × 1.0 1 Refer to NOTE.
Front fork and front fork cap bolt M40 × 1.0 2 28 2.8 20
Front fork and base valve M22 × 1.0 2 55 5.5 40
Front fork cap bolt and damper rod M10 × 1.0 2 15 1.5 11
Front fork bleed screw and front fork cap bolt M5 × 0.8 2 1 0.1 0.7
Front fork and front fork protector M6 × 1.0 6 7 0.7 5.1
Front fork and brake hose guide M5 × 0.8 1 4 0.4 2.2
Front fork and brake hose holder M6 × 1.0 1 10 1.0 7.2
Throttle grip cap M5 × 0.8 2 4 0.4 2.2
Throttle cable cap M4 × 0.7 2 1 0.1 0.7
Front brake master cylinder M6 × 1.0 2 9 0.9 6.5
Brake lever mounting bolt M6 × 1.0 1 6 0.6 4.3
Brake lever mounting nut M6 × 1.0 1 6 0.6 4.3
Brake lever position locknut M6 × 1.0 1 5 0.5 3.6
Clutch lever holder M5 × 0.8 2 4 0.4 2.2
Front brake master cylinder cap M4 × 0.7 2 2 0.2 1.4
Front brake hose union bolt M10 × 1.25 2 26 2.6 19
Front fork and brake caliper bracket M8 × 1.25 2 30 3.0 22
Brake caliper support bolt M8 × 1.25 1 23 2.3 17
Front brake caliper and bleed screw M7 × 1.0 1 6 0.6 4.3
Rear brake caliper and brake caliper bracket M8 × 1.25 2 23 2.3 17
Rear brake caliper and pad pin M10 × 1.0 2 18 1.8 13
Rear brake caliper and bleed screw M8 × 1.25 1 6 0.6 4.3
Front wheel axle and axle nut M12 × 1.25 1 70 7.0 50
Front brake disc M6 × 1.0 3 12 1.2 8.7
Rear brake disc M6 × 1.0 4 12 1.2 8.7
Rear brake master cylinder M6 × 1.0 2 10 1.0 7.2
Rear brake reservoir tank M6 × 1.0 1 10 1.0 7.2
Rear brake hose union bolt M10 × 1.25 2 26 2.6 19
Rear wheel axle and axle nut M14 × 1.5 1 90 9.0 65

2 - 16
SPEC
EC240000
CABLE ROUTING DIAGRAM
1Hose guide
2Brake hose
3Throttle cable
4Fuel tank breather hose
5Engine stop switch lead
6CDI magneto lead
7Clamp
8Carburetor breather hose
9Carburetor overflow hose
0Transmission oil breather hose
ARadiator breather hose
BClutch cable
CSpark plug leadDCable guide
EBrake hose holder
ÈPass the fuel tank breather hose between the
handlebar and tension bar, then insert its end
into the hole of the steering stem.
ÉFasten the ground lead together with the ignition
coil.
ÊClamp the brake hose with the brake hose
holder.
ËFit the brake hose into the guides of the protec-
tor.
CABLE ROUTING DIAGRAM

2 - 17
SPEC
1Sub-wire harness
2CDI unit
3Ignition coil
4Clutch cable
5Cable guide
6Transmission oil breather hose
7CDI unit band
8Clamp
9Brake hose
0Brake hose holder
AHose guide
BReservoir hose
CReservoir tank
DBrake master cylinderÈPass the transmission oil breather hose through
the hose guide.
ÉClamp the sub-wire harness at the tape on it
within the arrow mark.
ÊPass the sub-wire harness on the left of the CDI
unit.
ËPass the reservoir hose between the brake hose
and swingarm bracket.
ÌPass the reservoir hose through the hose guides.
ÍInstall the brake hose so that its pipe portion
directs as shown and lightly touches the projec-
tion on the brake master cylinder.
CABLE ROUTING DIAGRAM

2 - 18
SPEC
1Throttle cable
2Clutch cable
3Clamp
4Engine stop switch lead
5Brake hose
6Hose guideÈFasten the engine stop switch lead to the han-
dlebar with the plastic band.
ÉPass the brake hose in front of the number plate.
ÊCross the clutch cable and throttle cable over
the number plate boss.
CABLE ROUTING DIAGRAM

3 - 1
INSP
ADJ
MAINTENANCE INTERVALS
EC300000
REGULAR INSPECTION AND ADJUSTMENTS
MAINTENANCE INTERVALS
The following schedule is intended as a general guide to maintenance and lubrication. Bear in mind
that such factors as weather, terrain, geographical location, and individual usage will alter the
required maintenance and lubrication intervals. If you are a doubt as to what intervals to follow in
maintaining and lubricating your machine, consult your Yamaha dealer.
ItemAfter
break-inEvery
raceEvery
third
raceEvery
fifth
raceAs re-
quiredRemarks
PISTON
Inspect and clean
Replace







Inspect crack
Inspect carbon deposits
and eliminate them
PISTON RING
Inspect
Replace





Check ring end gap
PISTON PIN, SMALL END BEARING
Inspect
Replace




CYLINDER HEAD
Inspect and clean
Retighten







Inspect carbon deposits
and eliminate them
Check gasket
CYLINDER
Inspect and clean
Replace




Inspect score marks
Inspect wear
CLUTCH
Inspect and adjust
Replace





Inspect housing, friction
plate, clutch plate and
spring
TRANSMISSION
Replace oil
Inspect
Replace bearing






Yamalube 4 (10W-30) or
SAE 10W-30 SE motor oil
SHIFT FORK, SHIFT CAM, GUIDE BAR
Inspect

Inspect wear
ROTOR NUT
Retighten




KICK SHAFT
Inspect idle gear
Replace




EXHAUST PIPE, SILENCER
Inspect
Clean





CRANK
Inspect and clean



CARBURETOR
Inspect, adjust and clean



SPARK PLUG
Inspect and clean
Replace





DRIVE CHAIN
Lubricate, slack, alignment
Replace




Chain slack: 35 ~ 45 mm
(1.4 ~ 1.8 in)

3 - 4
INSP
ADJ
PRE-OPERATION INSPECTION AND MAINTENANCE
EC320000
PRE-OPERATION INSPECTION AND MAINTENANCE
Before riding for break-in operation, practice or a race, make sure the machine is in good operating
condition.
Before using this machine, check the following points.
GENERAL INSPECTION AND MAINTENANCE
Item Routine Page
CoolantCheck that coolant is filled up to the radiator cap.
Check the cooling system for leakage.P.3-5 ~ 9
FuelCheck that a fresh mixture of oil and gasoline is filled in the fuel
tank. Check the fuel line for leakage.P.1-12
Transmission oilCheck that the oil level is correct. Check the crankcase for leak-
age.P.3-12 ~ 13
Gear shifter and clutchCheck that gears can be shifted correctly in order and that the
clutch operates smoothly.P.3-9
Throttle grip/HousingCheck that the throttle grip operation and free play are correctly
adjusted. Lubricate the throttle grip and housing, if necessary.P.3-10
Brakes Check the play of front brake and effect of front and rear brake. P.3-16 ~ 21
Drive chainCheck drive chain slack and alignment. Check that the drive
chain is lubricated properly.P.3-22 ~ 24
WheelsCheck for excessive wear and tire pressure. Check for loose
spokes and have no excessive play.P.3-31 ~ 32
SteeringCheck that the handlebar can be turned smoothly and have no
excessive play.P.3-32 ~ 34
Front forks and rear shock
absorberCheck that they operate smoothly and there is no oil leakage. P.3-24 ~ 30
Cables (wires)Check that the clutch and throttle cables move smoothly. Check
that they are not caught when the handlebars are turned or
when the front forks travel up and down.—
Exhaust pipe and silencerCheck that the exhaust pipe is tightly mounted and has no
cracks.P.4-2
Rear wheel sprocket Check that the rear wheel sprocket tightening bolt is not loose. P.3-22
Lubrication Check for smooth operation. Lubricate if necessary. P.3-35
Bolts and nuts Check the chassis and engine for loose bolts and nuts. P.1-16
Lead connectorsCheck that the CDI magneto, CDI unit, and ignition coil are con-
nected tightly.P.1-6
SettingsIs the machine set suitably for the condition of the racing course
and weather or by taking into account the results of test runs
before racing? Are inspection and maintenance completely
done?P.7-1 ~ 19

3 - 9
INSP
ADJ
CLUTCH ADJUSTMENT
CAUTION:

Do not apply pressure more than speci-
fied pressure.

Radiator should be filled fully.
4. Inspect:

Pressure
Impossible to maintain the specified pres-
sure for 10 seconds → Repair.

Radiator 1

Radiator hose joint 2
Coolant leakage → Repair or replace.

Radiator hose 3
Swelling → Replace.
5PA30080
CLUTCH ADJUSTMENT
1. Check:

Clutch lever free play a
Out of specification → Adjust.
Clutch lever free play
a:
10 ~ 15 mm (0.39 ~ 0.59 in)
5PA30090
2. Adjust:

Clutch lever free play
NOTE:

Make minute adjustment on the lever side.

After adjustment, check proper operation of
clutch lever. Clutch lever free play adjustment steps:

Loosen the locknut 1.

Turn the adjuster 2 until free play a is
within the specified limits.

Tighten the locknut.
5PA30100