2007 YAMAHA WR 450F check oil

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INSP
ADJ
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).
Timing light:
YM-33277-A/90890-03141
1
3. Adjust:
Engine idling speed
Refer to “IDLE SPEED ADJUSTMENT”.
4. Check:
Ignition timing
Visually check the stationary pointer a is
within the firing range b on the rotor.
Incorrect firing range → Check rotor and
pickup assembly.
5. Install:
Timing plug

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ENGCAMSHAFTS
Decompression system
1. Check:
Decompression system
Checking steps:
Check that the decompressor cam 1
moves smoothly.
Check that the decompressor lever pin 2
projects from the camshaft.
Timing chain tensioner
1. Check:
While pressing the tensioner rod lightly
with fingers, use a thin screwdriver 1
and wind the tensioner rod up fully clock-
wise.
When releasing the screwdriver by press-
ing lightly with fingers, make sure that the
tensioner rod will come out smoothly.
If not, replace the tensioner assembly.
ASSEMBLY AND INSTALLATION
1. Install:
Exhaust camshaft 1
Intake camshaft 2
Installation steps:
Turn the crankshaft counterclockwise until
the “I” mark a on the rotor is aligned with
the stationary pointer b on the crankcase
cover.
NOTE:
Apply the molybdenum disulfide oil on the
camshafts.
Apply the engine oil on the decompression
system.

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ENGCLUTCH
3. Bend the lock washer 1 tab.
4. Install:
Friction plate 1
Clutch plate 1
[t = 2.0 mm (0.079 in)] 2
Clutch plate 2
[t = 1.6 mm (0.063 in)] 3
NOTE:
Install the clutch plates and friction plates
alternately on the clutch boss, starting with a
friction plate and ending with a friction plate.
Apply the engine oil on the friction plates and
clutch plates.
Check the clutch plate for thickness and
install 4 thicker ones a on the engine side
and 3 thinner ones b on the outside.
ab
5. Install:
Bearing 1
Plain washer 2
Circlip 3
To push rod 1 4.
NOTE:
Apply the engine oil on the bearing and plain
washer.
New
6. Install:
Push rod 2 1
Ball 2
Push rod 1 3
NOTE:
Apply the engine oil on the push rod 1, 2 and
ball.

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ENGOIL PUMP
INSPECTION
Oil pump
1. Inspect:
Oil pump drive gear
Oil pump driven gear
Rotor housing
Oil pump cover
Cracks/wear/damage → Replace.
2. Measure:
Tip clearance a
Between the inner rotor 1 and the outer
rotor 2.
Tip clearance b
Between the outer rotor 2 and the rotor
housing 3.
Out of specification → Replace the oil
pump.
3. Check:
Unsmooth → Repeat steps #1 and #2 or
replace the defective parts.
ASSEMBLY AND INSTALLATION
Oil pump
1. Install:
Oil pump drive shaft 1
Washer 2
Pin 3
Inner rotor 1 4
NOTE:
Apply the engine oil on the oil pump drive
shaft and inner rotor 1.
Fit the pin into the groove in the inner rotor 1.
Tip clearance
a:
0.12 mm or less
(0.0047 in or less)
: 0.20 mm (0.008 in)
Tip clearance
b:
0.09 ~ 0.17 mm
(0.0035 ~ 0.0067 in)
: 0.24 mm (0.009 in)
Side clearance
c:
0.03 ~ 0.10 mm
(0.0012 ~ 0.0039 in)
: 0.17 mm (0.007 in)

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ENGCRANKCASE AND CRANKSHAFT
NOTE:
Hold the connecting rod at top dead center
with one hand while turning the nut of the
installing tool with the other. Operate the
installing tool until the crankshaft bottoms
against the bearing.
Before installing the crankshaft, clean the
contacting surface of crankcase.
CAUTION:
Do not use a hammer to drive in the crank-
shaft.
2. Check:
Shifter operation
Transmission operation
Unsmooth operation → Repair.
3. Install:
Oil strainer 1
Bolt (oil strainer) 2
4. Apply:
Sealant
On the crankcase (right).
NOTE:
Clean the contacting surface of crankcase (left
and right) before applying the sealant.
YAMAHA Bond No. 1215
(ThreeBond® No. 1215):
90890-85505
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)

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ENGCRANKCASE AND CRANKSHAFT
5. Install:
Dowel pin 1
O-ring 2
Crankcase (right)
To crankcase (left).
NOTE:
Fit the crankcase (right) onto the crankcase
(left). Tap lightly on the case with soft ham-
mer.
When installing the crankcase, the connect-
ing rod should be positioned at TDC (top
dead center).
New
6. Tighten:
Hose guide 1
Clutch cable holder 2
Bolt (clutch cable holder)
Bolt (crankcase)
NOTE:
Tighten the crankcase tightening bolts in
stage, using a crisscross pattern.
7. Install:
Timing chain
Timing chain guide (rear)
Bolt (timing chain guide)
8. Remove:
Sealant
Forced out on the cylinder mating surface.
9. Apply:
Engine oil
To the crank pin, bearing and oil delivery
hole.
10. Check:
Crankshaft and transmission operation.
Unsmooth operation → Repair.
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
T R..12 Nm (1.2 m · kg, 8.7 ft · lb)
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)

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ENGTRANSMISSION, SHIFT CAM AND SHIFT FORK
6. Install:
Transmission assembly 1
To crankcase (left) 2.
NOTE:
Apply the engine oil on the bearings and guide
bars.
7. Check:
Shifter operation
Transmission operation
Unsmooth operation → Repair.

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CHASFRONT FORK
13. Check:
Inner tube smooth movement
Tightness/binding/rough spots → Repeat
the steps 2 to 12.
14. Compress the front fork fully.
15. Fill:
Front fork oil
Until outer tube top surface with recom-
mended fork oil 1.
CAUTION:
Be sure to use recommended fork oil. If
other oils are used, they may have an
excessively adverse effect on the front
fork performance.
Never allow foreign materials to enter the
front fork.
Recommended oil:
Suspension oil “S1”
16. After filling, pump the damper rod 1 slowly
up and down more than 10 times to distrib-
ute the fork oil.
17. Fill:
Front fork oil
Until outer tube top surface with recom-
mended fork oil once more.
18. After filling, pump the outer tube 1 slowly
up and down (about 200 mm (7.9 in)
stroke) to distribute the fork oil once more.
NOTE:
Be careful not to excessive full stroke. A stroke
of 200 mm (7.9 in) or more will cause air to
enter. In this case, repeat the steps 15 to 18.