torque YAMAHA YZ85 2002 Owners Manual

EC0A0000
CONTENTS
CHAPTER 1
GENERAL INFORMATION
DESCRIPTION
........................................... 1-1
MACHINE IDENTIFICATION
..................... 1-2
IMPORTANT INFORMATION
.................... 1-3
CHECKING OF CONNECTION
................. 1-6
SPECIAL TOOLS
...................................... 1-7
CONTROL FUNCTIONS
............................ 1-9
FUEL AND ENGINE MIXING OIL
............ 1-12
STARTING AND BREAK-IN
.................... 1-13
TORQUE-CHECK POINTS
...................... 1-16
CLEANING AND STORAGE
................... 1-17
CHAPTER 2
SPECIFICATIONS
GENERAL SPECIFICATIONS
................... 2-1
MAINTENANCE SPECIFICATIONS
.......... 2-4
ENGINE
................................................... 2-4
CHASSIS
................................................. 2-8
YZ85
..................................................... 2-8
YZ85LW
.............................................. 2-10
ELECTRICAL
........................................ 2-14
GENERAL TORQUE
SPECIFICATIONS
................................... 2-15
DEFINITION OF UNITS
........................... 2-15
CABLE ROUTING DIAGRAM
................. 2-16

1 - 15
GEN
INFO
STARTING AND BREAK-IN
CAUTION:
lAfter the break-in or before each race,
you must check the entire machine for
loose fittings and fasteners as per
“TORQUE-CHECK POINTS”.
Tighten all such fasteners as required.
lWhen any of the following parts have
been replaced, they must be broken in.
CYLINDER AND CRANKSHAFT:
About one hour of break-in operation is
necessary.
PISTON, RING AND GEARS:
These parts require about 30 minutes of
break-in operation at half-throttle or less.
Observe the condition of the engine care-
fully during operation.

GEN
INFO
1 - 16
TORQUE-CHECK POINTS
TORQUE-CHECK POINTS
Frame construction
Combined seat and fuel tank
Engine mounting
Steering Steering stem to
handlebar
Suspension Front Steering stem to front
fork
Rear For link type
Rear Installation of rear
shock absorber
Rear Installation of swin-
garm
Wheel Installation of wheel Front
Rear
Brake Front
Rear
Fuel systemFrame to rear frame
Fuel tank to frame
Frame to engine
Steering stem to upper bracket
Upper bracket to handlebar
Front fork to upper bracket
Front fork to lower bracket
Assembly of links
Link to frame
Link to rear shock absorber
Link to swingarm
Rear shock absorber to frame
Tightening of pivot shaft
Tightening of wheel axle
Tightening of wheel axle
Wheel to rear wheel sprocket
Brake caliper to front fork
Brake disc to wheel
Tightening of union bolt
Brake master cylinder to handlebar
Tightening of bleed screw
Brake caliper to bracket
Brake disc to wheel
Tightening of union bolt
Brake master cylinder to frame
Tightening of bleed screw
Fuel tank to fuel cock
NOTE:
Concerning the tightening torque, refer to
“MAINTENANCE SPECIFICATIONS” section
in the CHAPTER 2.

SPEC
2 - 7
MAINTENANCE SPECIFICATIONS
Part to be tightened Thread size Q’tyTightening torque
Nm m·kg ft·lb
Spark plug M14 ´ 1.25 1 20 2.0 14
Cylinder head (nut) M8 ´ 1.25 4 30 3.0 22
(stud bolt) M8 ´ 1.25 4 13 1.3 9.4
Cylinder (nut) M8 ´ 1.25 4 28 2.8 20
(stud bolt) M8 ´ 1.25 4 13 1.3 9.4
Impeller M8 ´ 1.25 1 14 1.4 10
Coolant drain bolt M6 ´ 1.0 1 10 1.0 7.2
Water pump housing M6 ´ 1.0 2 10 1.0 7.2
Air filter element M6 ´ 1.0 1 2 0.2 1.4
Carburetor joint M6 ´ 1.0 4 8 0.8 5.8
Reed valve M3 ´ 0.5 4 1 0.1 0.7
Exhaust pipe M6 ´ 1.0 2 12 1.2 8.7
Exhaust pipe stay M6 ´ 1.0 1 12 1.2 8.7
Silencer M6 ´ 1.0 1 12 1.2 8.7
Fiber (silencer) M6 ´ 1.0 2 10 1.0 7.2
Crankcase M6 ´ 1.0 11 8 0.8 5.8
Left crankcase cover M6 ´ 1.0 4 5 0.5 3.6
Right crankcase cover M6 ´ 1.0 4 10 1.0 7.2
Right crankcase cover M6 ´ 1.0 1 10 1.0 7.2
Clutch cover M6 ´ 1.0 6 10 1.0 7.2
Transmission oil drain bolt M8 ´ 1.25 1 10 1.0 7.2
Kickstarter crank M6 ´ 1.0 1 10 1.0 7.2
Primary drive gear M12 ´ 1.0 1 79 7.9 57
Clutch boss M12 ´ 1.0 1 70 7.0 50
Clutch spring M5 ´ 0.8 5 6 0.6 4.3
Drive sprocket M16 ´ 1.0 1 60 6.0 43
Crankcase bearing stopper M6 ´ 1.0 2 8 0.8 5.8
Shift pedal M6 ´ 1.0 1 10 1.0 7.2

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 1 115 11.5 85
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 1 110 11.0 80

SPEC
2 - 13
MAINTENANCE SPECIFICATIONS
NOTE:
- marked portion shall be checked for torque tightening after break-in or before each race.Part to be tightened Thread size Q’tyTightening torque
Nm m·kg ft·lb
Nipple (spoke) — 64 3 0.3 2.2
Rear wheel sprocket M8 ´ 1.25 4 42 4.2 30
Rear brake caliper protector M6 ´ 1.0 1 10 1.0 7.2
Engine mounting:
Engine and frame (front) M10 ´ 1.25 1 69 6.9 50
Engine and frame (lower) M10 ´ 1.25 1 69 6.9 50
Pivot shaft and nut M12 ´ 1.25 1 63 6.3 45
Relay arm and frame M10 ´ 1.25 1 54 5.4 39
Relay arm and connecting rod M12 ´ 1.25 1 53 5.3 38
Connecting rod and swingarm M12 ´ 1.25 1 53 5.3 38
Rear shock absorber and frame M10 ´ 1.25 1 36 3.6 25
Rear shock absorber and relay arm M10 ´ 1.25 1 36 3.6 25
Rear frame (upper) M8 ´ 1.25 1 26 2.6 19
Rear frame (lower) M8 ´ 1.25 2 16 1.6 11
Swingarm and brake hose holder M5 ´ — 4 4 0.4 2.9
Drive chain tensioner (upper) M8 ´ 1.25 1 23 2.3 17
Drive chain tensioner (lower) M6 ´ 1.0 1 10 1.0 7.2
Drive chain case M8 ´ 1.25 2 11 1.1 8
Seal guard and swingarm M6 ´ 1.0 2 10 1.0 7.2
Fuel tank M6 ´ 1.0 2 7 0.7 5.1
Fuel cock M6 ´ 1.0 2 4 0.4 2.9
Fuel tank bracket and fuel tank M6 ´ 1.0 4 7 0.7 5.1
Seat set bracket and fuel tank M6 ´ 1.0 1 7 0.7 5.1
Radiator cover M6 ´ 1.0 3 4 0.4 2.9
Front fender M6 ´ 1.0 4 7 0.7 5.1
Rear fender M6 ´ 1.0 4 7 0.7 5.1
Flap guard M6 ´ 1.0 2 7 0.7 5.1
Side cover M6 ´ 1.0 2 7 0.7 5.1
Seat M6 ´ 1.0 2 7 0.7 5.1
Number plate M6 ´ 1.0 1 7 0.7 5.1

SPEC
2 - 14
MAINTENANCE SPECIFICATIONS
EC212300
ELECTRICAL
Item Standard Limit
Ignition system:
Ignition timing (B.T.D.C.) 0.9 mm (0.035 in) ----
Advancer type Electrical ----
CDI:
Magneto-model (stator)/manufac-
turer5PA-00/YAMAHA ----
Charging coil 1 resistance (color) 720 ~ 1,080 W at 20 °C (68 °F)
(Green/White – Black/Red)----
Charging coil 2 resistance (color) 44 ~ 66 W at 20 °C (68 °F)
(Black – Green/Blue)----
Pickup coil resistance (color) 248 ~ 372 W at 20 °C (68 °F)
(White/Blue – White/Red)----
CDI unit-model/manufacturer 5PA-00/YAMAHA ----
Ignition coil:
Model/manufacturer 5PA-00/YAMAHA ----
Minimum spark gap 6 mm (0.24 in) ----
Primary coil resistance 0.18 ~ 0.28 W at 20 °C (68 °F) ----
Secondary coil resistance 6.3 ~ 9.5 kW at 20 °C (68 °F) ----
Part to be tightened Thread size Q’tyTightening torque
Nm m·kg ft·lb
Stator M6 ´ 1.0 2 8 0.8 5.8
Rotor M10 ´ 1.25 1 33 3.3 24
Ignition coil M6 ´ 1.0 2 7 0.7 5.1

2 - 15
SPEC
EC220001
GENERAL TORQUE SPECIFICATIONS
This chart specifies torque for standard fasten-
ers with standard I.S.O. pitch threads. Torque
specifications for special components or
assemblies are included in the applicable sec-
tions of this book. To avoid warpage, tighten
multi-fastener assemblies in a crisscross fash-
ion, in progressive stages, until full torque is
reached. Unless otherwise specified, torque
specifications call for clean, dry threads. Com-
ponents should be at room temperature.
A: Distance between flats
B: Outside thread diameter
EC230000
DEFINITION OF UNITS
A
(Nut)B
(Bolt)TORQUE
SPECIFICATION
Nm m•kg ft•lb
10 mm
12 mm
14 mm
17 mm
19 mm
22 mm6 mm
8 mm
10 mm
12 mm
14 mm
16 mm6
15
30
55
85
1300.6
1.5
3.0
5.5
8.5
134.3
11
22
40
61
94
5PA20050
Unit Read Definition Measure
mm
cmmillimeter
centimeter10
-3 meter
10-2 meterLength
Length
kg kilogram 10
3 gram Weight
N Newton 1 kg
´ m/sec
2 Force
Nm
m • kgNewton meter
Meter kilogramN
´ m
m
´ kgTorque
Torque
Pa Pascal N/m
2Pressure
N/mm Newton per millimeter N/mm Spring rate
L
cm
3 Liter
Cubic centimeter—
—Volume or capacity
Volume or capacity
r/min Revolution per minute — Engine speed
GENERAL TORQUE SPECIFICATIONS/
DEFINITION OF UNITS

3 - 33
INSP
ADJ
STEERING HEAD INSPECTION AND ADJUSTMENT
lTighten the steering ring nut 3 using
steering nut wrench 4.
NOTE:
Set the torque wrench to the steering nut
wrench so that they form a right angle.
Steering nut wrench:
YU-33975/90890-01403
T R..
Steering ring nut (initial tighten-
ing):
38 Nm (3.8 m • kg, 27 ft • lb)
lLoosen the steering ring nut one turn.
lRetighten the steering ring nut using the
steering nut wrench.
WARNING
Avoid over-tightening.
T R..
Steering ring nut (final tighten-
ing):
4 Nm (0.4 m • kg, 2.9 ft • lb)
lCheck the steering stem by turning it lock
to lock. If there is any binding, remove the
steering stem assembly and inspect the
steering bearings.
lInstall the upper bracket 5, steering stem
nut 6, handlebar 7, handlebar upper
holder 8 and number plate 9.
NOTE:
lThe upper handlebar holder should be
installed with the punched mark a for-
ward.
lInsert the end of fuel breather hose 0 into
the hole of the steering stem.
CAUTION:
First tighten the bolts on the front side of
the handlebar holder, and then tighten
the bolts on the rear side.
T R..
Steering stem nut:
115 Nm (11.5 m • kg, 85 ft • lb)
Handlebar upper holder:
27 Nm (2.7 m • kg, 19 ft • lb)
Pinch bolt (upper bracket):
22 Nm (2.2 m • kg, 16 ft • lb)
Number plate:
7 Nm (0.7 m • kg, 5.1 ft • lb)
5PA30750
5PA30760

5 - 38
CHAS
25. Loosen:
lRebound damping adjuster 1
NOTE:
lLoosen the rebound damping adjuster finger
tight.
lRecord the set position of the adjuster (the
amount of turning out the fully turned in posi-
tion).
5PA51170
26. Install:
lFront fork cap bolt 1
Fully tighten the front fork cap bolt onto the
damper rod by hand.
NOTE:
Make sure that there is a clearance a of Zero
~ 1 mm (Zero ~ 0.04 in) between the front fork
cap bolt and locknut 2.
5PA51180
27. Tighten:
lFront fork cap bolt (locknut) 1
NOTE:
Hold the locknut 2 and tighten the front fork
cap bolt with specified torque.
5PA51190
T R..15 Nm (1.5 m · kg, 11 ft · lb)
28. Install:
lFront fork cap bolt 1
To outer tube.
NOTE:
Temporarily tighten the cap bolt.
5PA51200
29. Install:
lProtector guide 1
5PA51210
FRONT FORK