2003 YAMAHA WR 450F engine oil

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INSP
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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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ENGINE OIL LEVEL INSPECTION
(For USA and CDN)
CAUTION:
Do not add any chemical additives.
Engine oil also lubricates the clutch and
additives could cause clutch slippage.
Do not allow foreign material to enter the
crankcase.
(Except for USA and CDN)
CAUTION:
Do not add any chemical additives or use
oils with a grade of CD a or higher.
Do not use oils labeled “ENERGY CON-
SERVING II” b or higher. Engine oil also
lubricates the clutch and additives could
cause clutch slippage.
Do not allow foreign materials to enter the
crankcase.
5. Start the engine and let it warm up for
several minutes.
CAUTION:
When the oil tank is empty, never start the
engine.
Recommended oil:
At 5 ˚C (40 ˚F) or higher Å
Yamalube 4 (20W-40) or SAE
20W-40 type SG motor oil
(Non-Friction modified)
At 15 ˚C (60 ˚F) or lower ı
Yamalube 4 (10W-30) or SAE
10W-30 type SG motor oil
(Non-Friction modified)
and/or
Yamalube 4-R (15W-50)
(Non-Friction modified)
Recommended oil:
Refer to the following chart for
selection of oils which are suited
to the atmospheric temperatures.
Recommended engine oil classi-
fication:
API STANDARD:
API “SG” or higher grade
(Designed primarily for motor-
cycles)-20
-4-10
140
3010
5020
6830
8640 50
104
122°CTemp.
°F
10W-30
10W-40
20W-40
20W-50
15W-40
a
b

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ENGINE OIL REPLACEMENT
6. Idle the engine more than 10 seconds
while keeping the motorcycle upright.
Then stop the engine and add the oil to
the maximum level.
7. Install:
Oil tank cap
ENGINE OIL REPLACEMENT
1. Start the engine and let it warm up for
several minutes.
2. Stop the engine and place an oil pan
under the drain bolt.
3. Remove:
Oil tank plug 1
Oil filler cap 2
Drain bolt (with gasket) 3
Oil filter drain bolt (O-ring) 4
Drain bolt (with gasket) 5
Drain bolt (with gasket) 6
Drain the crankcase and oil tank
(frame) of its oil.
4. Remove:
Engine skid plate
Engine oil hose clamp 1
Bolt (engine oil hose) 2
Engine oil hose 3
Oil strainer (frame) 4
5. Clean:
Oil strainer (frame)

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INSP
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ENGINE OIL REPLACEMENT
6. If the oil filter is to be replaced during this
oil change, remove the following parts
and reinstall them.
7. Install:
Plain washer 1
Oil strainer (frame) 2
Engine oil hose 3
Bolt (engine oil hose) 4
Engine oil hose clamp 5
Engine skid plate
8. Install:
Gaskets
Oil filter drain bolt
Drain bolt (crankcase rear)
Drain bolt (crankcase left)
Drain bolt (frame)
9. Fill:
Crankcase
10. Install:
Oil filler plug
11. Inspect:
Engine (for oil leaks)
Oil level
Refer to “ENGINE OIL LEVEL INSPEC-
TION”. Replacement steps:
Remove the exhaust pipe.
Remove the oil filter cover 1 and oil filter
element 2.
Check the O-rings 3, if cracked or dam-
aged, replace them with a new one.
Install the oil filter element and oil filter
cover.
T R..
Oil filter cover:
10 Nm (1.0 m • kg, 7.2 ft • lb)
Oil quantity:
Total amount:
1.2 L (1.06 Imp qt, 1.27 US qt)
Periodic oil change:
1.0 L (0.88 Imp qt, 1.06 US qt)
With oil filter replacement:
1.1 L (0.97 Imp qt, 1.16 US qt)
New
T R..90 Nm (9.0 m · kg, 65 ft · lb)
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
T R..2 Nm (0.2 m · kg, 1.4 ft · lb)
New
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
T R..20 Nm (2.0 m · kg, 14 ft · lb)
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
T R..23 Nm (2.3 m · kg, 17 ft · lb)

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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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Round off the last digit of the installed pad
number to the nearest increment.
Last digit of pad
numberRounded value
0, 1 or 2 0
4, 5 or 6 5
8 or 9 10
EXAMPLE:
Installed pad number = 148
Rounded off value = 150
NOTE:
Pads can only be selected in 0.05 mm incre-
ments.
Locate the rounded-off value and the
measured valve clearance in the chart
“PAD SELECTION TABLE”. The field
where these two coordinates intersect
shows the new pad number to use.
NOTE:
Use the new pad number only as a guide
when verifying the valve clearance adjust-
ment.
Install the new pads 6 and the valve lift-
ers 7.
NOTE:
Apply the engine oil on the valve lifters.
Apply the molybdenum disulfide oil on the
valve stem ends.
Valve lifter must turn smoothly when
rotated with a finger.
Be careful to reinstall valve lifters and
pads in their original place.
Install the camshafts (exhaust and intake),
the timing chain and the camshaft caps.
Refer to “CAMSHAFTS” section in the
CHAPTER 4.
T R..
Bolt (camshaft cap):
10 Nm (1.0 m • kg, 7.2 ft • lb)
VALVE CLEARANCE ADJUSTMENT

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IGNITION TIMING CHECK
IGNITION TIMING CHECK
1. Remove:
Timing plug 1
1
2. Attach:
Timing light
Inductive tachometer
To the ignition coil lead (orange lead
1).
3. Check:
Ignition timing
Timing light:
YM-33277-A/90890-03141
Inductive tachometer:
YU-8036-B
Engine tachometer:
90890-03113
Checking steps:
Start the engine and let it warm up. Let the
engine run at the specified speed.
Adjust the engine idling speed.
Refer to “IDLE SPEED ADJUSTMENT”
section.
Visually check the stationary pointer a is
within the firing range b on the rotor.
Incorrect firing range → Check rotor and
pickup assembly.
1
4. Install:
Timing plug

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ENGCAMSHAFTS
CAMSHAFTS
CYLINDER HEAD COVER
Extent of removal:1 Cylinder head cover removal
Extent of removal Order Part name Q’ty Remarks
CYLINDER HEAD COVER
REMOVAL
Preparation for removal Seat and fuel tank Refer to “SEAT, FUEL TANK AND SIDE
COVERS” section.
Carburetor Refer to “CARBURETOR” section.
1 Spark plug 1
2 Engine upper bracket (right) 1
3 Engine upper bracket (left) 1
4 Cylinder head breather hose 1
5 Oil tank breather hose 1
6 Bolt (cylinder head cover) 2
7 Cylinder head cover 1
8 Gasket 1
9 Timing chain guide (upper) 1
1