2003 YAMAHA WR 450F light

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SPECCABLE ROUTING DIAGRAM
1Starter motor lead
2Negative battery lead
3Wire harness
4Clamp
5Taillight lead
6Coolant reservoir tank
breather hose
7Coolant reservoir hose
8Positive battery lead
9Starting circuit cut-off
relay
0BatteryÅPosition the starter motor lead,
negative battery lead and wire
harness in the tank damper slit.
ıFasten the wire harness to the
frame with a plastic locking tie and
cut off the tie end.
ÇDo not allow the taillight lead to
slacken.
ÎPass the starter motor lead and
negative battery lead over the car-
buretor.
‰Fasten the coolant reservoir tank
breather hose, coolant reservoir
hose and rectifier/regulator lead to
the frame with a plastic band.ÏFasten the coolant reservoir tank
breather hose and coolant reser-
voir hose to the frame with a plas-
tic band.
ÌPass the coolant reservoir hose
on the outside of the coolant res-
ervoir tank breather hose.

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SPECCABLE ROUTING DIAGRAM
1Throttle cable
2Brake hose
3Clamp
4Lights switch lead
5Hot starter cable
6Clutch cable
7Hose guide
8Clutch switch lead
9“ENGINE STOP” button
lead
0Trip meter cable
AMain switch lead
BTrip meter
CMain switch
DLights switch
EStart switch leadÅFasten the start switch lead and
lights switch lead to the handlebar
with a plastic band.
ıFasten the “ENGINE STOP” but-
ton lead and clutch switch lead to
the handlebar with the plastic
bands.
ÇPass the brake hose through the
hose guide.
ÎPass the start switch lead in front
of the main switch lead.
‰Fasten the start switch lead to the
handlebar with a plastic band.
ÏPass the hot starter cable and
lights switch lead between the
handle crown and coupler
bracket.ÌPass the throttle cables and clutch
cable between the handle crown
and trip meter.

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INSP
ADJ
ENGINE OIL LEVEL INSPECTION
ENGINE OIL LEVEL INSPECTION
1. Stand the motorcycle on a level surface.
NOTE:
When checking the oil level make sure that
the motorcycle is upright.
Place the motorcycle on a suitable stand.
WARNING
Never remove the oil tank cap just after
high speed operation. The heated oil could
spurt out. causing danger. Wait until the oil
cools down to approximately 70 ˚C (158 ˚F).
2. Idle the engine more than 3 minutes
while keeping the motorcycle upright.
Then stop the engine and inspect the oil
level.
3. Remove:
Oil tank cap 1
1
4. Inspect:
Oil level
Oil level should be between maximum
a and minimum b marks.
Oil level low → Add oil to proper level.
NOTE:
When inspecting the oil level, do not screw the
oil level gauge into the oil tank.
Insert the gauge lightly.
a
b

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INSP
ADJ
PILOT SCREW ADJUSTMENT
12. Check:
Oil pressure
Checking steps:
Slightly loosen the oil gallery bolt 1.
Start the engine and keep it idling until oil
starts to seep from the oil gallery bolt. If no
oil comes out after one minute, turn the
engine off so it will not seize.
Check oil passages, oil filter and oil pump
for damage or leakage.
Start the engine after solving the prob-
lem(s) and recheck the oil pressure.
Tighten the oil gallery bolt to specification.
T R..
Oil gallery bolt:
10 Nm (1.0 m • kg, 7.2 ft • lb)
PILOT SCREW ADJUSTMENT
1. Adjust:
Pilot screw 1
* Except for USAAdjusting steps:
NOTE:
To optimize the fuel flow at a smaller throttle
opening, each machine’s pilot screw has
been individually set at the factory. Before
adjusting the pilot screw, turn it in fully and
count the number of turns. Record this num-
ber as the factory-set number of turns out.
Turn in the pilot screw until it is lightly
seated.
Turn out the pilot screw by the factory-set
number of turns.
Pilot screw:
1-3/4 turns out (example)
*1-1/2 turns out (example)

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INSP
ADJ
SPARK ARRESTER CLEANING (For USA)
WARNING
Be sure the exhaust pipe and muffler are
cool before cleaning the spark arrester.
Do not start the engine when cleaning the
exhaust system.
1. Remove:
Bolt (spark arrester) 1 1
1
2. Remove:
Spark arrester 1
Pull the spark arrester out of the muf-
fler.
1
3. Clean:
Spark arrester
Tap the spark arrester lightly, then use
a wire brush to remove any carbon
deposits.
4. Install:
Spark arrester
Insert the spark arrester into the muffler
and align the bolt holes.
Bolt (spark arrester)
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
SPARK ARRESTER CLEANING (For USA)

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INSP
ADJ
STEERING HEAD INSPECTION AND ADJUSTMENT
2. Inspect:
Bearing free play
Exist play → Replace.
STEERING HEAD INSPECTION AND
ADJUSTMENT
1. Elevate the front wheel by placing a suit-
able stand under the engine.
2. Check:
Steering shaft
Grasp the bottom of the forks and gen-
tly rock the fork assembly back and
forth.
Free play → Adjust steering head.
3. Check:
Steering smooth action
Turn the handlebar lock to lock.
Unsmooth action → Adjust steering ring
nut.
4. Adjust:
Steering ring nut
Steering ring nut adjustment steps:
Remove the headlight.
Remove the handlebar and handle crown.
Loosen the ring nut 1 using the ring nut
wrench 2.
Ring nut wrench:
YU-33975/90890-01403

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INSP
ADJ
STEERING HEAD INSPECTION AND ADJUSTMENT
Tighten the ring nut 3 using ring nut
wrench 4.
NOTE:
Set the torque wrench to the ring nut wrench
so that they form a right angle.
Ring nut wrench:
YU-33975/90890-01403
T R..
Ring nut (initial tightening):
38 Nm (3.8 m • kg, 27 ft • lb)
Loosen the ring nut one turn.
Retighten the ring nut using the ring nut
wrench.
WARNING
Avoid over-tightening.
T R..
Ring nut (final tightening):
7 Nm (0.7 m • kg, 5.1 ft • lb)
Check the steering shaft by turning it lock
to lock. If there is any binding, remove the
steering shaft assembly and inspect the
steering bearings.
Install the plain washer 5, handle crown
6, plain washer 7, steering shaft nut 8,
steering shaft cap 9, handlebar 0, han-
dlebar holder A and headlight B.
NOTE:
The handlebar holder should be installed
with the punched mark a forward.
Insert the end of the fuel breather hose C
into the hole in the steering shaft cap.
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 shaft nut:
145 Nm (14.5 m • kg, 105 ft • lb)
Handlebar holder:
28 Nm (2.8 m • kg, 20 ft • lb)
Pinch bolt (handle crown):
23 Nm (2.3 m • kg, 17 ft • lb)
Headlight (left and right):
10 Nm (1.0 m • kg, 7.2 ft • lb)
Headlight (lower):
7 Nm (0.7 m • kg, 5.1 ft • lb)

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INSP
ADJ
LUBRICATION
LUBRICATION
To ensure smooth operation of all compo-
nents, lubricate your machine during setup,
after break-in, and after every race.
1All control cable
2Clutch lever pivot
3Shift pedal pivot
4Footrest pivot
5Throttle-to-handlebar contact
6Drive chain
7Tube guide cable winding portion
8Throttle cable end
9Clutch cable end
0Hot starter cable endÅUse Yamaha cable lube or equivalent on these
areas.
ıUse SAE 10W-30 motor oil or suitable chain
lubricants.
ÇLubricate the following areas with high quality,
lightweight lithium-soap base grease.
CAUTION:
Wipe off any excess grease, and avoid get-
ting grease on the brake discs.
AAA
AAB
CC