2001 YAMAHA WR 426F clutch

ENG
4 - 56
CLUTCH (WR400F)
Extent of removal Order Part name Q’ty Remarks
11 Friction plate 2 1
12 Clutch plate 7
13 Friction plate 1 7
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
19 Push lever 1
4
1
3

4 - 57
ENGCLUTCH (WR400F)
EC493000
REMOVAL POINTS
EC483211
Clutch boss
1. Remove:
lNut 1
lLock washer 2
lClutch boss 3
NOTE:
Straighten the lock washer tab and use the
clutch holding tool 4 to hold the clutch boss.
For USA and CDN
õExcept for USA and CDN
Clutch holding tool:
YM-91042/90890-04086
õ
EC494000
INSPECTION
EC484100
Clutch housing and boss
1. Inspect:
lClutch housing 1
Cracks/wear/damage ® Replace.
lClutch boss 2
Scoring/wear/damage ® Replace.
EC484201
Primary driven gear
1. Check:
lCircumferential play
Free play exists ® Replace.
lGear teeth a
Wear/damage ® Replace.
EC484400
Clutch spring
1. Measure:
lClutch spring free length a
Out of specification ® Replace springs
as a set.
Clutch spring free length:
Standard
44 mm (1.73 in) 43 mm (1.69 in)

4 - 58
ENGCLUTCH (WR400F)
EC484500
Friction plate
1. Measure:
lFriction plate thickness
Out of specification ® Replace friction
plate as a set.
Measure at all four points.
EC484600
Clutch plate
1. Measure:
lClutch plate warpage
Out of specification ® Replace clutch
plate as a set.
Use a surface plate 1 and thickness
gauge 2.
Friction plate thickness:
Friction plate 1 [ø112 mm (4.41 in)]:
2.72 ~ 2.88 mm
(0.107 ~ 0.113 in)
: 2.52 mm (0.099 in)
Friction plate 2 [ø116 mm (4.57 in)]:
2.92 ~ 3.08 mm
(0.115 ~ 0.121 in)
: 2.72 mm (0.107 in)
Warp limit:
0.1 mm (0.004 in)
Push lever
1. Inspect:
lPush lever 1
Wear/damage ® Replace.
EC484810
Push rod
1. Inspect:
lPush rod 1 1
lBearing 2
lPlain washer 3
lPush rod 2 4
Wear/damage/bend ® Replace.

4 - 59
ENGCLUTCH (WR400F)
EC4A5000
ASSEMBLY AND INSTALLATION
Push lever
1. Install:
lPush lever 1
lBolt (push lever)
NOTE:
lApply the lithium soap base grease on the oil
seal lip.
lApply the engine oil on the push lever.
lFit the seat plate 2 in the groove a of the
push lever 1 and tighten the bolt (seat
plate).
2
1
a
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
Clutch
1. Install:
lPrimary driven gear 1
lThrust washer 2
lClutch boss 3
NOTE:
Apply the engine oil on the primary driven gear
inner circumference.
2. Install:
lLock washer 1
lNut (clutch boss) 2
NOTE:
Use the clutch holding tool 3 to hold the clutch
boss.
For USA and CDN
õExcept for USA and CDN
Clutch holding tool:
YM-91042/90890-04086
New
T R..75 Nm (7.5 m · kg, 54 ft · lb)

õ

4 - 60
ENGCLUTCH (WR400F)
3. Bend the lock washer 1 tab.
4. Install:
lFriction plate 1 [d = ø112 mm (4.41 in)]
1
lClutch plate 2
lFriction plate 2 [d = ø116 mm (4.57 in)]
3
NOTE:
lInstall the clutch plates and friction plates
alternately on the clutch boss, starting with a
friction plate 1 and ending with a friction plate
2.
lApply the engine oil on the friction plates and
clutch plates.
5. Install:
lBearing 1
lPlain washer 2
lCirclip 3
To push rod 1 4.
NOTE:
Apply the engine oil on the bearing and plain
washer.
6. Install:
lPush rod 2 1
lPush rod 1 2
NOTE:
Apply the engine oil on the push rod 1, 2.
New
7. Install:
lPressure plate 1
NOTE:
Align the much mark a on the pressure plate
with the punched mark b on the clutch boss.

4 - 61
ENGCLUTCH (WR400F)
8. Install:
lClutch spring
lBolt (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:
lGasket (clutch cover) 1
lDowel pin 2
New
10. Install:
lClutch cover 1
lBolt (clutch cover)
NOTE:
Tighten the bolts in stage, using a crisscross
pattern.
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)

ENG
4 - 62
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

ENG
4 - 69
BALANCER
BALANCER
BALANCER
Extent of removal:1 Balancer drive gear2 Balancer
Extent of removal Order Part name Q’ty Remarks
BALANCER REMOVAL
Preparation for removal Clutch housing Refer to “CLUTCH” section.
Crankcase cover (right)Refer to “OIL FILTER, WATER PUMP AND
CRANKCASE COVER (RIGHT)” section.
Stator Refer to “CDI MAGNETO” section.
1 Nut (primary drive gear) 1
Refer to “REMOVAL POINTS”.
2 Nut (balancer) 1
3 Lock washer 1
4 Primary drive gear 1
5 Balancer drive gear 1
6 Lock washer 1
7 Balancer driven gear 1
8 Balancer 1 Refer to “REMOVAL POINTS”.
2
1
2