2002 YAMAHA WR 426F brake

4 - 90
ENGENGINE REMOVAL
EC4M3000
REMOVAL POINTS
EC4F3100
Drive sprocket
1. Remove:
Nut (drive sprocket) 1
Lock washer 2
NOTE:
Straighten the lock washer tab.
Loosen the nut while applying the rear brake.
2. Remove:
Drive sprocket 1
Drive chain 2
NOTE:
Remove the drive sprocket together with the
drive chain.
EC4M3301
Engine removal
1. Remove:
Pivot shaft 1
NOTE:
If the pivot shaft is pulled all the way out, the
swingarm will come loose. If possible, insert a
shaft of similar diameter into the other side of
the swingarm to support it.
2. Remove:
Engine 1
From right side.
NOTE:
Make sure that the couplers, hoses and cables
are disconnected.

4 - 91
ENGENGINE REMOVAL
EC4M5000
ASSEMBLY AND INSTALLATION
EC4M5160
Engine installation
1. Install:
Engine 1
Install the engine from right side.
Pivot shaft 2
Engine mounting bolt (lower) 3
Engine lower bracket 4
Bolt (engine bracket) 5
Engine mounting bolt (front) 6
Engine upper bracket (right) 7
Engine upper bracket (left) 8
Bolt (engine bracket) 9
Engine mounting bolt (upper) 0
EC4M5211
Brake pedal
1. Install:
Spring
Brake pedal 1
O-ring 2
Bolt (brake pedal) 3
Clip 4
NOTE:
Apply the lithium soap base grease on the
bolt, O-rings and brake pedal bracket.
Install the clip with its stopper portion a fac-
ing inward.
T R..85 Nm (8.5 m · kg, 61 ft · lb)
T R..69 Nm (6.9 m · kg, 50 ft · lb)
T R..34 Nm (3.4 m · kg, 24 ft · lb)
T R..69 Nm (6.9 m · kg, 50 ft · lb)
T R..34 Nm (3.4 m · kg, 24 ft · lb)
T R..55 Nm (5.5 m · kg, 40 ft · lb)
New
T R..26 Nm (2.6 m · kg, 19 ft · lb)
Drive sprocket
1. Install:
Drive sprocket 1
Drive chain 2
NOTE:
Install the drive sprocket together with the
drive chain.

4 - 92
ENGENGINE REMOVAL
2. Install:
Lock washer 1
Nut (drive sprocket) 2
NOTE:
Tighten the nut while applying the rear brake.
New
T R..75 Nm (7.5 m · kg, 54 ft · lb)
3. Bend the lock washer tab to lock the nut.
4. Install:
Chain guide
Chain cover 1
Screw (chain cover) 2
T R..8 Nm (0.8 m · kg, 5.8 ft · lb)
5. Install:
O-ring 1
Dowel pin 2
Oil hose 3
Bolt (oil hose) 4
NOTE:
Apply the lithium soap base grease on the O-
ring.
6. Install:
Spring 1
Pin 2
O-ring 3
Neutral switch 4
Screw (neutral switch) 5
NOTE:
Apply the lithium soap base grease on the O-
ring.
New
T R..10 Nm (1.0 m · kg, 7.2 ft · lb)
New
T R..4 Nm (0.4 m · kg, 2.9 ft · lb)

5 - 1
CHAS
EC500000
CHASSIS
EC590000
FRONT WHEEL AND REAR WHEEL
EC598000
FRONT WHEEL
Extent of removal:1 Front wheel removal2 Wheel bearing removal
3 Brake disc removal
Extent of removal Order Part name Q’ty Remarks
Preparation for removalFRONT WHEEL REMOVAL
Hold the machine by placing the
suitable stand under the engine.
WARNING
Support the machine securely so there is nodanger of it falling over.
1 Trip meter cable 1
2 Hose cover 1
3 Bolt (brake hose holder) 2 Only loosening.
4 Bolt (axle holder) 4 Only loosening.
5 Nut (front wheel axle) 1
6 Front wheel axle 1
7 Front wheel 1
8 Trip meter gear unit 1
9 Collar 1
10 Oil seal 1
11 Bearing 2 Refer to “REMOVAL POINTS”.
12 Brake disc 1
2
31
3
FRONT WHEEL AND REAR WHEEL

5 - 2
CHAS
EC598100
REAR WHEEL
Extent of removal:1 Rear wheel removal2 Wheel bearing removal
3 Brake disc removal
Extent of removal Order Part name Q’ty Remarks
Preparation for removalREAR WHEEL REMOVAL
Hold the machine by placing the
suitable stand under the engine.
WARNING
Support the machine securely so there is nodanger of it falling over.
1 Nut (rear wheel axle) 1
2 Rear wheel axle 1
3 Chain puller 2
4 Rear wheel 1 Refer to “REMOVAL POINTS”.
5 Collar 2
6 Driven sprocket 1
7 Oil seal 2
8 Circlip 1
9 Bearing 2 Refer to “REMOVAL POINTS”.
10Brake disc
1
2
31
3
FRONT WHEEL AND REAR WHEEL

5 - 4
CHASFRONT WHEEL AND REAR WHEEL
EC514200
Wheel axle
1. Measure:
Wheel axle bends
Out of specification → Replace.
Use the dial gauge 1.
NOTE:
The bending value is shown by one half of the
dial gauge reading.
WARNING
Do not attempt to straighten a bent axle.
Wheel axle bending limit:
0.5 mm (0.020 in)
EC594200
Brake disc
1. Measure:
Brake disc deflection (only rear brake
disc)
Use the dial gauge 1.
Out of specification → Inspect wheel
runout.
If wheel runout is in good condition,
replace the brake disc.
2. Measure:
Brake disc thickness a
Out of limit → Replace.
Disc deflection limit:
Standard
Rear—0.15 mm
(0.006 in)
Disc wear limit:
Standard
Front3.0 mm
(0.12 in)2.5 mm
(0.10 in)
Rear4.0 mm
(0.16 in)3.5 mm
(0.14 in)

5 - 5
CHASFRONT WHEEL AND REAR WHEEL
EC595000
ASSEMBLY AND INSTALLATION
Front wheel
1. Install:
Bearing (left) 1
Spacer 2
Bearing (right) 3
Oil seal 4
NOTE:
Apply the lithium soap base grease on the
bearing and oil seal lip when installing.
Use a socket that matches the outside diam-
eter of the race of the bearing.
Left side of bearing shall be installed first.
Install the oil seal with its manufacture’s
marks or numbers facing outward.
CAUTION:
Do not strike the inner race of the bearing.
Contact should be made only with the outer
race.
2. Install:
Brake disc 1
Bolt (brake disc) 2
NOTE:
Tighten the bolts in stage, using a crisscross
pattern.
New
T R..12 Nm (1.2 m · kg, 8.7 ft · lb)
3. Install:
Collar 1
NOTE:
Apply the lithium soap base grease on the oil
seal lip.
Install the collar with their projection a fac-
ing the wheel.
4. Install:
Trip meter gear unit 1
NOTE:
Make sure the two projections a in the wheel
hub are meshed with the two slots b in the trip
meter gear unit.b a1

5 - 6
CHASFRONT WHEEL AND REAR WHEEL
5. Install:
Wheel
NOTE:
Install the brake disc between the brake
pads correctly.
Make sure that the projections a in the trip
meter gear unit fits over the stopper b on
the front fork outer tube.
6. Install:
Wheel axle 1
NOTE:
Apply the lithium soap base grease on the
wheel axle.
7. Install:
Nut (wheel axle) 1
T R..105 Nm (10.5 m · kg, 75 ft · lb)
8. Tighten:
Bolt (axle holder) 1
NOTE:
Before tightening the bolt, fit the wheel axle to
the axle holder by stroking the front fork sev-
eral times with the front brake applied.
T R..23 Nm (2.3 m · kg, 17 ft · lb)