2005 YAMAHA YZ85 radiator

CHAPTER 3
REGULAR INSPECTION
AND ADJUSTMENTS
MAINTENANCE INTERVALS................... 3-1
PRE-OPERATION INSPECTION
AND MAINTENANCE................................ 3-4
ENGINE...................................................... 3-5
CHASSIS................................................. 3-16
ELECTRICAL........................................... 3-36
CHAPTER 4
ENGINE
SEAT, FUEL TANK
AND SIDE COVERS.................................. 4-1
EXHAUST PIPE AND SILENCER............. 4-2
RADIATOR................................................ 4-3
CARBURETOR AND REED VALVE......... 4-6
CYLINDER HEAD, CYLINDER
AND PISTON........................................... 4-15
CLUTCH AND PRIMARY
DRIVEN GEAR........................................ 4-26
KICK SHAFT, SHIFT SHAFT
AND PRIMARY DRIVE GEAR................. 4-33
WATER PUMP......................................... 4-41
CDI MAGNETO........................................ 4-45
ENGINE REMOVAL................................. 4-49
CRANKCASE AND CRANKSHAFT........ 4-53
TRANSMISSION, SHIFT CAM
AND SHIFT FORK................................... 4-59

GEN
INFO
1 - 1
DESCRIPTION
EC100000
GENERAL INFORMATION
EC110000
DESCRIPTION
1Clutch lever
2Engine stop switch
3Front brake lever
4Throttle grip
5Fuel tank cap
6Radiator cap
7Kickstarter crank
8Fuel tank
9Coolant drain bolt
0Rear brake pedal
ARadiator
BValve joint
CFuel cock
DAir filter
EDrive chain
FShift pedal
GStarter knob
HFront forkNOTE:

The machine you have purchased may differ
slightly from those shown in the following.

Designs and specifications are subject to
change without notice.
5PA10020
5PA10010
5PAR0001

GEN
INFO
1 - 7
SPECIAL TOOLS
EC140002
SPECIAL TOOLS
The proper special tools are necessary for complete and accurate tune-up and assembly. Using the
correct special tool will help prevent damage caused by the use of improper tools or improvised
techniques. The shape and part number used for the special tool differ by country, so two types are
provided. Refer to the list provided to avoid errors when placing an order.
NOTE:

For U.S.A. and Canada, use part number starting with “YM-”, “YU-” or “ACC-”.

For others, use part number starting with “90890-”.
Part number Tool name/How to use Illustration
YU-1135-A, 90890-01135 Crankcase separating tool
This tool is used to split the crankcase as well as
remove the crankshaft from either case.YU-1135-A 90890-01135
YM-1189, 90890-01189 Flywheel puller
This tool is used to remove the flywheel magneto.YM-1189 90890-01189
YU-1235, 90890-01235 Rotor holding tool
This tool is used when loosening or tightening the fly-
wheel magneto securing nut.YU-1235 90890-01235
YU-3097, 90890-01252
YU-1256Dial gauge and stand
Stand
These tools are used to check each part for runout or
bent.YU-3097
YU-125690890-01252
YU-90050, 90890-01274
YU-90050, 90890-01275
YM-1277, 90890-01277Crankshaft installing tool
Crankshaft installing pot
Crankshaft installing bolt
Adapter (M10)
These tools are used to install the crankshaft.YU-90050
YM-127790890-01274
90890-01275
90890-01277
YU-1304, 90890-01304 Piston pin puller set
This tool is used to remove the piston pin.YU-1304 90890-01304
YU-24460-01, 90890-01325
YU-33984, 90890-01352Radiator cap tester
Radiator cap tester adapter
These tools are used for checking the cooling sys-
tem.YU-24460-01
YU-3398490890-01325
90890-01352
5PA102105PA10210
5PA102205PA10220
5PA10240
5PA102505PA10260
5PA102705PA10270
5PA102805PA10290

SPEC
2 - 6
MAINTENANCE SPECIFICATIONS
Reed valve:
Thickness “T”0.42 mm (0.017 in) ----
Valve stopper height 7.4 ~ 7.8 mm (0.291 ~ 0.307 in) ----
Valve bending limit ---- 0.2 mm
(0.008 in)
Cooling:
Radiator core size
Width 117.8 mm (4.64 in) ----
Height 240 mm (9.45 in) ----
Thickness 32 mm (1.26 in) ----
Radiator cap opening pressure 95 ~ 125 kPa (0.95 ~ 1.25 kg/cm
2,
13.5 ~ 17.8 psi)----
Radiator capacity 0.32 L (0.28 Imp qt, 0.34 US qt) ----
Water pump
Type Single-suction centrifugal pump ----Item Standard Limit

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
Radiator hose clamp M6 × 1.0 4 1 0.1 0.7
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 12 1.2 8.7
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
Crankcase oil seal holder M8 × 1.25 1 20 2.0 14
Shift pedal M6 × 1.0 1 10 1.0 7.2

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
Drive chain puller adjust bolt and locknut M8 × 1.25 2 16 1.6 11
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 × 0.8 4 1 0.1 0.7
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 support M8 × 1.25 2 16 1.6 11
Drive chain support cover M6 × 1.0 1 7 0.7 5.1
Drive chain guide 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

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

3 - 2
INSP
ADJ
MAINTENANCE INTERVALS
COOLING SYSTEM
Check coolant level and leakage
Check radiator cap operation
Replace coolant
Inspect hoses








Every two years
OUTSIDE NUTS AND BOLTS
Retighten



AIR FILTER
Clean and lubricate
Replace




Use foam air-filter oil or
equivalent oil
FRAME
Clean and inspect



FUEL TANK, COCK
Clean and inspect



BRAKES
Adjust lever position and pedal height
Lubricate pivot point
Check brake disc surface
Check fluid level and leakage
Retighten brake disc bolts, caliper
bolts, master cylinder bolts and union
bolts
Replace pads
Replace brake fluid























Every one year
FRONT FORKS
Inspect and adjust
Replace oil
Replace oil seal









Suspension oil “01”
FRONT FORK OIL SEAL AND DUST
SEAL
Clean and lube


Lithium base grease
REAR SHOCK ABSORBER
Inspect and adjust
Lube
Retighten







(After
rain ride)


Molybdenum disulfide
grease
DRIVE CHAIN GUIDE, ROLLERS AND
SUPPORT
Inspect


SWINGARM
Inspect and retighten
Lube







Molybdenum disulfide
grease
RELAY ARM, CONNECTING ROD
Inspect and retighten
Lube







Molybdenum disulfide
grease
STEERING HEAD
Inspect free play and retighten
Clean and lube
Replace bearing







Lithium base grease ItemAfter
break-inEvery
raceEvery
third
raceEvery
fifth
raceAs re-
quiredRemarks


3