2006 YAMAHA WR 450F fork

2 - 29
SPECCABLE ROUTING DIAGRAM
ÒPass the speed sensor lead
through the guide on the out-
side of the front fork.
ÓPass the start switch lead and
multi-function display lead (on
the wire harness side) above
the multi-function display lead
(on the side of the multi-func-
tion display lead) and speed
sensor lead, and then to the
right of the chassis.
4
5
Î
Ê Ó
A
B
F-FE-E
C
D
A
D
7
7
Ò ËA
12
È32
É
6
Ê
6
8
Ì0
9
ËÑ C
BÏ
2
Ð 8
8
1Í
4
5
4
5B2
C
DC BB A
F F
EE
EE
Ë
2

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
race
Every
third
(or
500 km)Every
fifth
(or
1,000 km)As re-
quiredRemarks
ENGINE OIL
Replace
VALVES
The engine must be cold.
Check the valve seats
and valve stems for wear. Check the valve clearances
Inspect
Replace
VALVE SPRINGS
Check the free length and
the tilt. Inspect
Replace
VALVE LIFTERS
Check for scratches and
wear. Inspect
Replace
CAMSHAFTS Inspect the camshaft sur-
face.
Inspect the decompres-
sion system Inspect
Replace
CAMSHAFT SPROCKETS
Check for wear on the
teeth and for damage. Inspect
Replace
PISTON
Inspect crack
Inspect carbon deposits
and eliminate them. Inspect
Clean
Replace
PISTON RING
Check ring end gap Inspect
Replace
PISTON PIN
Inspect
Replace
CYLINDER HEAD Inspect carbon deposits
and eliminate them.
Change gasket Inspect and clean
CYLINDER
Inspect and clean
Inspect score marks
Inspect wear
Replace
CLUTCH
Inspect housing, friction
plate, clutch plate and
spring Inspect and adjust
Replace
TRANSMISSION
Inspect
Replace bearing
SHIFT FORK, SHIFT CAM, GUIDE BAR
InspectInspect wear

3 - 3
INSP
ADJ
MAINTENANCE INTERVALS
* marked: For USA
FRONT FORKS
Inspect and adjust
Replace oil Suspension oil “S1”
Replace oil seal
FRONT FORK OIL SEAL AND DUST
SEAL
Clean and lube Lithium base grease
PROTECTOR GUIDE
Replace
REAR SHOCK ABSORBER
(After
rain ride)
Inspect and adjust
Lube
Molybdenum disulfide
grease
Retighten
DRIVE CHAIN GUARD AND ROLL-
ERS
Inspect
DRIVE CHAIN STOPPER
Inspect
SWINGARM
Molybdenum disulfide
grease
Inspect, lube and retighten
RELAY ARM, CONNECTING ROD
Molybdenum disulfide
grease
Inspect, lube and retighten
SIDESTAND
Lubricate Lithium base grease
STEERING HEAD
Inspect free play and retighten
Clean and lube Lithium base grease
Replace bearing
TIRE, WHEELS
Inspect air pressure, wheel run-out,
tire wear and spoke looseness
Retighten sprocket bolt
Inspect bearings
Replace bearings
Lubricate Lithium base grease
THROTTLE, CONTROL CABLE
Yamaha cable lube or
SAE 10W-30 motor oil Check routing and connection
Lubricate
HOT STARTER, CLUTCH LEVER
Inspect free play
BATTERY
Check terminal for looseness and
corrosionItemAfter
break-inEvery
race
Every
third
(or
500 km)Every
fifth
(or
1,000 km)As re-
quiredRemarks

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 filler cap.
Check the cooling system for leakage.P.3-5 ~ 9
FuelCheck that a fresh gasoline is filled in the fuel tank. Check the
fuel line for leakage.P.1-21
Engine oilCheck that the oil level is correct. Check the crankcase and
frame oil line for leakage.P.3-14 ~ 18
Gear shifter and clutchCheck that gears can be shifted correctly in order and that the
clutch operates smoothly.P.3-10
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 ~ 11
Brakes Check the play of front brake and effect of front and rear brake. P.3-25 ~ 31
ChainCheck chain slack and alignment. Check that the chain is lubri-
cated properly.P.3-32 ~ 35
WheelsCheck for excessive wear and tire pressure. Check for loose
spokes and have no excessive play.P.3-43 ~ 44
SteeringCheck that the handlebar can be turned smoothly and have no
excessive play.P.3-44 ~ 46
Front forks and rear shock
absorberCheck that they operate smoothly and there is no oil leakage. P.3-35 ~ 42
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.—
Muffler Check that the muffler is tightly mounted and has no cracks.—
Sprocket Check that the driven sprocket tightening bolt is not loose. P.3-32
Lubrication Check for smooth operation. Lubricate if necessary. P.3-47
Bolts and nuts Check the chassis and engine for loose bolts and nuts. P.1-26
Lead connectorsCheck that the AC 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 ~ 20

3 - 28
INSP
ADJ
FRONT BRAKE PAD INSPECTION AND REPLACEMENT
Loosen the pad pin 2.
Remove the caliper 3 from the front fork.
Remove the pad pin and brake pads 4.
Connect the transparent hose 5 to the
bleed screw 6 and place the suitable con-
tainer under its end.
Loosen the bleed screw and push the cali-
per piston in.
CAUTION:
Do not reuse the drained brake fluid.
Tighten the bleed screw.
T R..
Bleed screw:
6 Nm (0.6 m  kg, 4.3 ft  lb)
Install the brake pads 7 and pad pin.
NOTE:
Install the brake pads with their projections
a into the caliper recesses b.
Temporarily tighten the pad pin at this
point.
Install the caliper 8 and tighten the pad
pin 9.
T R..
Bolt (caliper):
23 Nm (2.3 m  kg, 17 ft  lb)
Pad pin:
18 Nm (1.8 m  kg, 13 ft  lb)

3 - 35
INSP
ADJDRIVE CHAIN STOPPER INSPECTION/FRONT FORK INSPECTION/
FRONT FORK OIL SEAL AND DUST SEAL CLEANING
Tighten the axle nut while pushing down
the drive chain.
T R..
Axle nut:
125 Nm (12.5 m  kg, 90 ft  lb)
Tighten the locknuts.
T R..
Locknut:
16 Nm (1.6 m  kg, 11 ft  lb)
DRIVE CHAIN STOPPER INSPECTION
1. Inspect:
Drive chain stopper 1
Wear indicator groove a has almost dis-
appeared → Replace.
2. Replace:
Drive chain stopper
1
1a
T R..7 Nm (0.7 m · kg, 5.1 ft · lb)
EC36C000
FRONT FORK INSPECTION
1. Inspect:
Front fork smooth action
Operate the front brake and stroke the
front fork.
Unsmooth action/oil leakage → Repair or
replace.
EC36D001
FRONT FORK OIL SEAL AND DUST SEAL
CLEANING
1. Remove:
Protector
Dust seal 1
NOTE:
Use a thin screw driver, and be careful not to
damage the inner fork tube and dust seal.
2. Clean:
Dust seal a
Oil seal b
NOTE:
Clean the dust seal and oil seal after every
run.
Apply the lithium soap base grease on the
inner tube.

3 - 36
INSP
ADJFRONT FORK INTERNAL PRESSURE RELIEVING/
FRONT FORK REBOUND DAMPING FORCE ADJUSTMENT
FRONT FORK INTERNAL PRESSURE
RELIEVING
NOTE:
If the front fork initial movement feels stiff dur-
ing a run, relieve the front fork internal pres-
sure.
1. Elevate the front wheel by placing a suit-
able stand under the engine.
2. Remove the air bleed screw 1 and release
the internal pressure from the front fork.
3. Install:
Air bleed screw
T R..1 Nm (0.1 m · kg, 0.7 ft · lb)
EC36H002
FRONT FORK REBOUND DAMPING FORCE
ADJUSTMENT
1. Adjust:
Rebound damping force
By turning the adjuster 1.
Stiffer a →Increase the rebound damp-
ing force. (Turn the adjuster
1 in.)
Softer b →Decrease the rebound damp-
ing force. (Turn the adjuster
1 out.)
Extent of adjustment:
Maximum Minimum
Fully turned in
position20 clicks out (from
maximum position)

3 - 37
INSP
ADJFRONT FORK COMPRESSION DAMPING FORCE
ADJUSTMENT
STANDARD POSITION:
This is the position which is back by the spe-
cific number of clicks from the fully turned-in
position.
* For EUROPE
** For AUS, NZ and ZA
CAUTION:
Do not force the adjuster past the minimum
or maximum extent of adjustment. The
adjuster may be damaged.
WARNING
Always adjust each front fork to the same
setting. Uneven adjustment can cause poor
handling and loss of stability.
EC36J001
FRONT FORK COMPRESSION DAMPING
FORCE ADJUSTMENT
1. Remove:
Rubber cap
2. Adjust:
Compression damping force
By turning the adjuster 1.
Standard position:
10 clicks out
* 11 clicks out
** 13 clicks out
Stiffer
a
→Increase the compression
damping force. (Turn the
adjuster
1 in.)
Softer
b
→Decrease the compression
damping force. (Turn the
adjuster
1 out.)
Extent of adjustment:
Maximum Minimum
Fully turned in
position20 clicks out (from
maximum position)