Yamaha Wr 450 F Owners Manual

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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 Part name Q’ty Remarks
CLUTCH REMOVAL
Preparation for removal Drain the engine oil. Refer to “ENGINE OIL REPLACEMENT” 
section in the CHAPTER 3.
Brake pedal Refer to “ENGINE REMOVAL” section.
Clutch cable Disconnect at engine side.
1 Clutch cover 1
2 Gasket 1
3 Dowel pin 2
4 Clutch spring 6
5 Pressure plate 1
6 Push rod 1 1
7 Circlip 1
8 Plain washer 1
9 Bearing 1
10 Ball 1
11Push rod 2
1
41
2
3
1 
						

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ENGCLUTCH
Extent of removal Order Part name Q’ty Remarks
12 Clutch plate 8
13 Friction plate 9
14 Nut 1
Use special tool.
Refer to “REMOVAL POINTS”. 15 Look washer 1
16 Clutch boss 1
17 Thrust washer 1
18 Clutch housing 1
19Push lever
1
4
1
3 
						

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ENGCLUTCH
EC493000
REMOVAL POINTS
EC483211
Clutch boss
1. Remove:
Nut 1 
Lock washer 2 
Clutch boss 3 
NOTE:
Straighten the lock washer tab and use the
clutch holding tool 4 to hold the clutch boss.
ÅFor USA and CDN
ıExcept for USA and CDN
Clutch holding tool:
YM-91042/90890-04086
Å
ı
EC494000
INSPECTION
EC484100
Clutch housing and boss
1. Inspect:
Clutch housing 1 
Cracks/wear/damage → Replace.
Clutch boss 2 
Scoring/wear/damage → Replace.
EC484201
Primary driven gear
1. Check:
Circumferential play
Free play exists → Replace.
Gear teeth a 
Wear/damage → Replace.
EC484400
Clutch spring
1. Measure:
Clutch spring free length a 
Out of specification → Replace springs
as a set.
Clutch spring free length:
Standard 
48.4 mm (1.91 in) 47.4 mm (1.87 in) 
						

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ENGCLUTCH
EC484500
Friction plate
1. Measure:
Friction plate thickness
Out of specification → Replace friction
plate as a set.
Measure at all four points.
EC484600
Clutch plate
1. Measure:
Clutch plate warpage
Out of specification → Replace clutch
plate as a set.
Use a surface plate 1 and thickness
gauge 2.
Friction plate thickness:
2.92 ~ 3.08 mm
(0.115 ~ 0.121 in)
: 2.8 mm (0.110 in)
Warp limit:
0.1 mm (0.004 in)
Push lever
1. Inspect:
Push lever 1 
Wear/damage → Replace.
EC484810
Push rod
1. Inspect:
Push rod 1 1 
Bearing 2 
Plain washer 3 
Push rod 2 4 
Ball 5 
Wear/damage/bend → Replace. 
						

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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 push lever.
Fit the seat plate 2 in the groove a of the
push lever and tighten the bolt (seat plate).
2
1a
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
Clutch
1. Install:
Primary driven gear 1
Thrust washer 2
Clutch boss 3
NOTE:
Apply the engine oil on the primary driven gear
inner circumference.
2. Install:
Lock washer 1 
Nut (clutch boss) 2
NOTE:
Use the clutch holding tool 3 to hold the clutch
boss.
ÅFor USA and CDN
ıExcept for USA and CDN
Clutch holding tool:
YM-91042/90890-04086
New
T R..75 Nm (7.5 m · kg, 54 ft · lb)
Åı 
						

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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
friction plate and ending with a friction plate.
Apply the engine oil on the friction plates and
clutch plates.
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.
7. Install:
Pressure plate 1  
						

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ENGCLUTCH
8. Install:
Clutch spring
Bolt (clutch spring)
NOTE:
Tighten the bolts in stage, using a crisscross
pattern.
T R..8 Nm (0.8 m · kg, 5.8 ft · lb)
9. Install:
Gasket (clutch cover) 1 
Dowel pin 2 
New
10. Install:
Clutch cover 1 
Bolt (clutch cover)
NOTE:
Tighten the bolts in stage, using a crisscross
pattern.
T R..10 Nm (1.0 m · kg, 7.2 ft · lb) 
						

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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 removal2 Water pump removal
3 Crankcase cover (right) removal
Extent of removal Order Part name Q’ty Remarks
OIL FILTER, WATER PUMP 
AND CRANKCASE COVER 
(RIGHT) REMOVAL
Preparation for removal Drain the engine oil. Refer to “ENGINE OIL REPLACEMENT” 
section in the CHAPTER 3.
Drain the coolant. Refer to “COOLANT REPLACEMENT” 
section in the CHAPTER 3.
Exhaust pipe Refer to “EXHAUST PIPE AND 
SILENCER” section.
Brake pedal Refer to “ENGINE REMOVAL” section.
Clutch cover Refer to “CLUTCH” section.
1 Oil filter cover 1
2 Oil filter 1
3 Coolant pipe 2 1
4 Water pump housing 1
5 Pin 2
6 Oil delivery pipe 1
1
2
3 
						

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ENG
OIL FILTER, WATER PUMP AND CRANKCASE COVER
(RIGHT)
Extent of removal Order Part name Q’ty Remarks
7 Oil hose 1
8 Kickstarter 1
9 Crankcase cover (right) 1
10 Gasket 1
11 Dowel pin/O-ring 4/2
12 Impeller 1
Refer to “REMOVAL POINTS”. 13 Plain washer 1
14 Impeller shaft 1
15 Oil seal 1 1
16 Oil seal 2 1
17 Bearing 1
2
3
2 
						

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ENG
OIL FILTER, WATER PUMP AND CRANKCASE COVER
(RIGHT)
REMOVAL POINTS
EC4G3110
Impeller shaft
1. Remove:
Impeller 1 
Plain washer 2 
Impeller shaft 3 
NOTE:
Hold the impeller shaft on its width across the
flats a with spanners, etc. and remove the
impeller.
EC4G3210
Oil seal
NOTE:
It is not necessary to disassemble the water
pump, unless there is an abnormality such as
excessive change in coolant level, discolora-
tion of coolant, or milky transmission oil.
1. Remove:
Bearing 1 
Oil seal 2 
INSPECTION
EC444200
Impeller shaft
1. Inspect:
Impeller shaft 1 
Bend/wear/damage → Replace.
Fur deposits → Clean.