engine YAMAHA WR 450F 2004 Repair Manual

YAMAHA WR 450F 2004 Repair Manual WR 450F 2004 YAMAHA YAMAHA https://www.carmanualsonline.info/img/51/52484/w960_52484-0.png YAMAHA WR 450F 2004 Repair Manual

Page 342 of 754

YAMAHA WR 450F 2004 Repair Manual 4 - 21
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

Page 352 of 754

YAMAHA WR 450F 2004 Repair Manual 4 - 26
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 c

Page 354 of 754

YAMAHA WR 450F 2004 Repair Manual 4 - 27
ENGCAMSHAFTS
Fit the timing chain 3 onto both camshaft
sprockets and install the camshafts on the
cylinder head.
NOTE:
The camshafts should be installed onto the
cylinder head so that the exha

Page 382 of 754

YAMAHA WR 450F 2004 Repair Manual 4 - 41
ENGVALVES AND VALVE SPRINGS
5. Install:
Adjusting pad 1 
Valve lifter 2 
NOTE:
Apply the engine oil on the valve lifters.
Apply the molybdenum disulfide oil on the
valve stem end.
Valve li

Page 392 of 754

YAMAHA WR 450F 2004 Repair Manual 4 - 46
ENGCYLINDER AND PISTON
Piston pin
1. Inspect:
Piston pin
Blue discoloration/grooves → Replace,
then inspect the lubrication system.
2. Measure:
Piston pin-to-piston clearance
ASSEMBLY AND I

Page 394 of 754

YAMAHA WR 450F 2004 Repair Manual 4 - 47
ENGCYLINDER AND PISTON
2. Position:
Top ring
2nd ring
Oil ring
Offset the piston ring end gaps as
shown.
aTop ring end
b2nd ring end
cOil ring end (upper)
dOil ring
eOil ring end (lower)
3.

Page 396 of 754

YAMAHA WR 450F 2004 Repair Manual 4 - 48
ENGCLUTCH
CLUTCH
CLUTCH
Extent of removal:1 Push rod and push lever removal2 Push pod 1 disassembly
3 Friction plate and clutch plate removal4 Clutch housing removal
Extent of removal Order Par

Page 404 of 754

YAMAHA WR 450F 2004 Repair Manual 4 - 52
ENGCLUTCH
EC4A5000
ASSEMBLY AND INSTALLATION
Push lever
1. Install:
Push lever 1 
Bolt (push lever)
NOTE:
Apply the lithium soap base grease on the oil
seal lip.
Apply the engine oil on the

Page 406 of 754

YAMAHA WR 450F 2004 Repair Manual 4 - 53
ENGCLUTCH
3. Bend the lock washer 1 tab.
4. Install:
Friction plate 1
Clutch plate 2
NOTE:
Install the clutch plates and friction plates
alternately on the clutch boss, starting with a
frict

Page 410 of 754

YAMAHA WR 450F 2004 Repair Manual 4 - 55
ENG
OIL FILTER, WATER PUMP AND CRANKCASE COVER
(RIGHT)
OIL FILTER, WATER PUMP AND CRANKCASE COVER (RIGHT)
OIL FILTER, WATER PUMP AND CRANKCASE COVER (RIGHT)
Extent of removal:1 Oil filter remov