2007 YAMAHA WR 450F engine

4 - 73
ENGOIL PUMP
2. Install:
Outer rotor 1 1
NOTE:
Apply the engine oil on the outer rotor 1.
3. Install:
Oil pump cover 1
Screw (oil pump cover) 2
Pin 3
Inner rotor 2 4
Circlip 5
NOTE:
Apply the engine oil on the oil pump drive
shaft end and inner rotor 2.
Fit the pin into the groove in the inner rotor 2.
T R..2 Nm (0.2 m · kg, 1.4 ft · lb)
New
4. Install:
Outer rotor 2 1
Dowel pin 2
Oil pump assembly 3
Bolt (oil pump assembly) 4
NOTE:
Apply the engine oil on the outer rotor 2.
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
5. Install:
Oil pump drive gear 1
Plain washer 2
Circlip 3
NOTE:
Apply the engine oil on the oil pump drive gear
inner circumference.
New

4 - 78
ENGKICK AXLE AND SHIFT SHAFT
EC4C5000
ASSEMBLY AND INSTALLATION
Segment
1. Install:
Segment 1
Bolt (segment)
NOTE:
Align the notch a on the segment with the pin
b on the shift cam.
CAUTION:
If the segment gets an impact, it may be
damaged. Take care not to give an impact
to the segment when tightening the bolt.
T R..30 Nm (3.0 m · kg, 22 ft · lb)
EC4B5111
Stopper lever
1. Install:
Torsion spring 1
Plain washer 2
Stopper lever 3
Bolt (stopper lever) 4
NOTE:
Align the stopper lever roller with the slot on
segment.
Shift guide and shift lever assembly
1. Install:
Spring 1
Pawl pin 2
Pawl 3
To shift lever 4.
NOTE:
Apply the engine oil on the springs, pawl pins
and pawls.
2. Install:
Shift lever assembly 1
To shift guide 2.
1
2
4
3T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
1
2

4 - 79
ENGKICK AXLE AND SHIFT SHAFT
3. Install:
Shift lever assembly 1
Shift guide 2
NOTE:
The shift lever assembly is installed at the
same time as the shift guide.
Apply the engine oil on the bolt (segment)
shaft.
4. Install:
Bolt (shift guide) 1
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
EC4C5301
Shift shaft
1. Install:
Roller 1
Collar 2
Torsion spring 3
Plain washer 4
Shift shaft 5
NOTE:
Apply the engine oil on the roller and shift
shaft.
2. Install:
Shift pedal
Refer to “AC MAGNETO AND STARTER
CLUTCH” section.

4 - 81
ENGKICK AXLE AND SHIFT SHAFT
4. Install:
Kick axle assembly 1
Plain washer 2
NOTE:
Apply the molybdenum disulfide grease on
the contacting surfaces of the kick axle stop-
per a and ratchet wheel guide 3.
Apply the engine oil on the kick axle.
Slide the kick axle assembly into the crank-
case and make sure the kick axle stopper fits
into the ratchet wheel guide.
5. Hook:
Torsion spring 1
NOTE:
Turn the torsion spring clockwise and hook
into the proper hole a in the crankcase.
Kick idle gear
1. Install:
Kick idle gear 1
Plain washer 2
Circlip 3
NOTE:
Install the kick idle gear with its depressed
side a toward you.
Apply the engine oil on the kick idle gear
inner circumference.
New

4 - 82
ENGAC MAGNETO AND STARTER CLUTCH
AC MAGNETO AND STARTER CLUTCH
Extent of removal:
1 Starter clutch/wheel gear removal
2 Rotor removal
3 Pickup coil/stator removal
Extent of removal Order Part name Q’ty Remarks
AC MAGNETO AND STATOR
REMOVAL
Preparation for removal Drain the engine oil. Refer to “ENGINE OIL REPLACEMENT”
section in the CHAPTER 3.
Seat and fuel tank Refer to “SEAT, FUEL TANK AND SIDE
COVERS” section.
Disconnect the AC magneto lead.
1 Shift pedal 1
2 Cover (torque limiter) 1
3 Torque limiter 1 Do not disassemble.
4 Crankcase cover (left) 1
5 Gasket 1
6 Dowel pin 2
13

4 - 86
ENGAC MAGNETO AND STARTER CLUTCH
EC4L5000
ASSEMBLY AND INSTALLATION
AC magneto and starter clutch
1. Install:
Stator 1
Bolt (stator) 2
Pick-up coil 3
Holder 4
Bolt 5
NOTE:
Pass the AC magneto lead 5 under the pick-
up coil.
Pass the AC magneto lead 4 under the
holder as shown.
Take care not to catch the AC magneto lead
between crankcase cover ribs.
Tighten the bolt (stator) using the T25 bit.
Apply the sealant to the grommet of the AC
magneto lead.
YAMAHA Bond No. 1215
(ThreeBond® No. 1215):
90890-85505
T R..7 Nm (0.7 m · kg, 5.1 ft · lb)
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
2. Install:
Starter clutch drive gear 1
NOTE:
Apply the engine oil on the starter clutch drive
gear inner circumference.

4 - 88
ENG
7. Install:
Shaft 1
Bearing 2
Idle gear 2 3
NOTE:
Apply the engine oil on the shaft, bearing and
idle gear inner circumference.
8. Install:
Dowel pin
Gasket [crankcase cover (left)]
Crankcase cover (left) 1
Bolt [crankcase cover (left)]
NOTE:
Tighten the bolts in stage, using a crisscross
pattern.
New
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
9. Install:
Plain washer
Torque limiter 1
Plain washer
NOTE:
Apply the engine oil to the shaft and plain
washers.1
10. Install:
Cover (idle gear 1) 1
Bolt 2
NOTE:
Install the cover (idle gear 1) with its mark a
facing upward.
11. Connect:
AC magneto lead
Refer to “CABLE ROUTING DIAGRAM”
section in the CHAPTER 2.
12. Install:
Shift pedal 1
Bolt (shift pedal)
NOTE:
When installing the shift pedal onto the shift
shaft, be sure that the center of the shift pedal
is about 5.1 mm (0.2 in) a above the top of the
footrest.
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
T R..12 Nm (1.2 m · kg, 8.7 ft · lb)
AC MAGNETO AND STARTER CLUTCH

4 - 89
ENGENGINE REMOVAL
EC4M0000
ENGINE REMOVAL
Extent of removal Order Part name Q’ty Remarks
ENGINE REMOVAL
Preparation for removal Hold the machine by placing the
suitable stand under the frame.
WARNING
Support the machine securely so there is nodanger of it falling over.
Drain the engine oil Refer to “ENGINE OIL REPLACEMENT”
section in the CHAPTER 3.
Seat, fuel tank and side cover Refer to “SEAT, FUEL TANK AND SIDE
COVERS” section.
Radiator Refer to “RADIATOR” section.
Exhaust pipe and silencer Refer to “EXHAUST PIPE AND
SILENCER” section.
Air cut-off valve assembly Refer to “AIR INDUCTION SYSTEM”
section.
Clutch cable and guide Disconnect at the engine side.
Shift pedal Refer to “AC MAGNETO AND
STARTER CLUTCH” section.
Rear shock absorber Refer to “REAR SHOCK ABSORBER”
section in the CHAPTER 6
Carburetor Refer to “CARBURETOR” section.