relay YAMAHA WR 426F 2002 Owners Manual

2 - 16
SPECMAINTENANCE SPECIFICATIONS (WR426F)
NOTE:
- marked portion shall be checked for torque tightening after break-in or before each race.Part to be tightened Thread size Q’tyTightening torque
Nm m·kg ft·lb
Rear wheel axle and nut M20 × 1.5 1 125 12.5 90
Driven sprocket and wheel hub M8 × 1.25 6 42 4.2 30
Nipple (spoke)—72 3 0.3 2.2
Disc cover and rear brake caliper M6 × 1.0 2 7 0.7 5.1
Protector and rear brake caliper M6 × 1.0 2 7 0.7 5.1
Engine mounting:
Engine bracket and frame M8 × 1.25 7 34 3.4 24
Engine and frame (front) M10 × 1.25 1 69 6.9 50
Engine and frame (upper) M10 × 1.25 1 55 5.5 40
Engine and frame (lower) M10 × 1.25 1 69 6.9 50
Engine guard (left and right) M8 × 1.25 2 23 2.3 17
Pivot shaft and nut M16 × 1.5 1 85 8.5 61
Relay arm and swingarm M14 × 1.5 1 80 8.0 58
Relay arm and connecting rod M14 × 1.5 1 80 8.0 58
Connecting rod and frame M14 × 1.5 1 80 8.0 58
Rear shock absorber and frame M10 × 1.25 1 56 5.6 40
Rear shock absorber and relay arm M10 × 1.25 1 53 5.3 38
Rear frame and frame M8 × 1.25 3 29 2.9 21
Swingarm and brake hose holder M5 × 0.8 4 1 0.1 0.7
Swingarm and patch M4 × 0.7 4 2 0.2 1.4
Drive chain tensioner mounting (upper) M8 × 1.25 1 19 1.9 13
Drive chain tensioner mounting (lower) M8 × 1.25 1 20 2.0 14
Chain support and swingarm M6 × 1.0 3 7 0.7 5.1
Seal guard and swingarm M5 × 0.8 4 6 0.6 4.3
Fuel tank mounting M6 × 1.0 2 10 1.0 7.2
Fuel tank and fuel cock M6 × 1.0 2 7 0.7 5.1
Fuel tank and seat set bracket M6 × 1.0 1 7 0.7 5.1
Fuel tank and hooking screw (fitting band) M6 × 1.0 1 7 0.7 5.1
Fuel tank and fuel tank bracket M6 × 1.0 4 7 0.7 5.1
Seat mounting M8 × 1.25 2 23 2.3 17
Side cover mounting M6 × 1.0 2 7 0.7 5.1
Air scoop and fuel tank M6 × 1.0 4 4 0.4 2.9
Air scoop and radiator panel (lower) M6 × 1.0 2 4 0.4 2.9
Front fender mounting M6 × 1.0 4 7 0.7 5.1
Rear fender and air filter case M6 × 1.0 2 7 0.7 5.1
Rear fender and frame (right) M6 × 1.0 1 10 1.0 7.2
Headlight stay (lower) and under bracket M8 × 1.25 2 7 0.7 5.1
Headlight (left and right) M6 × 1.0 2 10 1.0 7.2
Headlight (lower) M6 × 1.0 1 7 0.7 5.1
Tail light M6 × 1.0 3 4 0.4 2.9
Tail light lead clamp and rear fender M4 × 1.59 2 1 0.1 0.7
Coolant reservoir tank (front) M6 × 1.0 1 7 0.7 5.1
Coolant reservoir tank (rear) M6 × 1.0 1 11 1.1 8.0
Sidestand bracket and frame M10 × 1.25 2 66 6.6 48
Sidestand mounting M10 × 1.25 1 64 6.4 46

2 - 33
SPECMAINTENANCE SPECIFICATIONS (WR400F)
NOTE:
- marked portion shall be checked for torque tightening after break-in or before each race.Part to be tightened Thread size Q’tyTightening torque
Nm m·kg ft·lb
Rear wheel axle and nut M20 × 1.5 1 125 12.5 90
Driven sprocket and wheel hub M8 × 1.25 6 42 4.2 30
Nipple (spoke)—72 3 0.3 2.2
Disc cover and rear brake caliper M6 × 1.0 2 7 0.7 5.1
Protector and rear brake caliper M6 × 1.0 2 7 0.7 5.1
Engine mounting:
Engine bracket and frame M8 × 1.25 7 34 3.4 24
Engine and frame (front) M10 × 1.25 1 69 6.9 50
Engine and frame (upper) M10 × 1.25 1 55 5.5 40
Engine and frame (lower) M10 × 1.25 1 69 6.9 50
Engine guard (left and right) M8 × 1.25 2 23 2.3 17
Pivot shaft and nut M16 × 1.5 1 85 8.5 61
Relay arm and swingarm M14 × 1.5 1 80 8.0 58
Relay arm and connecting rod M14 × 1.5 1 80 8.0 58
Connecting rod and frame M14 × 1.5 1 80 8.0 58
Rear shock absorber and frame M10 × 1.25 1 56 5.6 40
Rear shock absorber and relay arm M10 × 1.25 1 53 5.3 38
Rear frame and frame M8 × 1.25 3 29 2.9 21
Swingarm and brake hose holder M5 × 0.8 4 1 0.1 0.7
Swingarm and patch M4 × 0.7 4 2 0.2 1.4
Drive chain tensioner mounting (upper) M8 × 1.25 1 19 1.9 13
Drive chain tensioner mounting (lower) M8 × 1.25 1 20 2.0 14
Chain support and swingarm M6 × 1.0 3 7 0.7 5.1
Seal guard and swingarm M5 × 0.8 4 6 0.6 4.3
Fuel tank mounting M6 × 1.0 2 10 1.0 7.2
Fuel tank and fuel cock M6 × 1.0 2 7 0.7 5.1
Fuel tank and seat set bracket M6 × 1.0 1 7 0.7 5.1
Fuel tank and hooking screw (fitting band) M6 × 1.0 1 7 0.7 5.1
Fuel tank and fuel tank bracket M6 × 1.0 4 7 0.7 5.1
Seat mounting M8 × 1.25 2 23 2.3 17
Side cover mounting M6 × 1.0 2 7 0.7 5.1
Air scoop and fuel tank M6 × 1.0 4 4 0.4 2.9
Air scoop and radiator panel (lower) M6 × 1.0 2 4 0.4 2.9
Front fender mounting M6 × 1.0 4 7 0.7 5.1
Rear fender and air filter case M6 × 1.0 2 7 0.7 5.1
Rear fender and frame (right) M6 × 1.0 1 10 1.0 7.2
Headlight stay (lower) and under bracket M8 × 1.25 2 7 0.7 5.1
Headlight (left and right) M6 × 1.0 2 10 1.0 7.2
Headlight (lower) M6 × 1.0 1 7 0.7 5.1
Tail light M6 × 1.0 3 4 0.4 2.9
Tail light lead clamp and rear fender M4 × 1.59 2 1 0.1 0.7
Coolant reservoir tank (front) M6 × 1.0 1 7 0.7 5.1
Coolant reservoir tank (rear) M6 × 1.0 1 11 1.1 8.0
Sidestand bracket and frame M10 × 1.25 2 66 6.6 48
Sidestand mounting M10 × 1.25 1 64 6.4 46

3 - 3
INSP
ADJ
MAINTENANCE INTERVALS
* marked: For USAFRONT FORKS
Inspect and adjust
Replace oil
Replace oil seal
●
●●
●
●
Suspension oil “01”
FRONT FORK OIL SEAL AND DUST
SEAL
Clean and lube
●●Lithium base grease
REAR SHOCK ABSORBER
Inspect and adjust
Lube
Retighten
●
●●
●●(After
rain ride)
●Molybdenum disulfide
grease
CHAIN GUARD AND ROLLERS
Inspect
●●
SWINGARM
Inspect, lube and retighten
●●
Molybdenum disulfide
grease
RELAY ARM, CONNECTING ROD
Inspect, lube and retighten
●●
Molybdenum disulfide
grease
STEERING HEAD
Inspect free play and retighten
Clean and lube
Replace bearing
●●
●
●Lithium base grease
TIRE, WHEELS
Inspect air pressure, wheel run-out,
tire wear and spoke looseness
Retighten sprocket bolt
Inspect bearings
Replace bearings
Lubricate
●
●●
●
●
●●
Lithium base grease
THROTTLE, CONTROL CABLE
Check routing and connection
Lubricate
Inspect and clean (throttle cable)
●
●
●●
●
●Yamaha cable lube or
SAE 10W-30 motor oil
Inspect dirt and wear on
the throttle cable on the
carburetor side. ItemAfter
break-inEvery
race
Every
third
or
500 km
(300 mi)Every
fifth
or
1,000 km
(600 mi)
As re-
quiredRemarks

5 - 53
CHASSWINGARM
EC570000
SWINGARM
Extent of removal:1 Swingarm removal
Extent of removal Order Part name Q’ty Remarks
SWINGARM REMOVAL
WARNING
Support the machine securely so there is no
danger of it falling over.
Preparation for removal Hold the machine by placing the
suitable stand under the engine.
Brake hose holder
Rear caliper
Bolt (brake pedal)
Drive chainRefer to “FRONT BRAKE AND REAR
BRAKE” section.
Shift the brake pedal backward.
1 Chain support 1
2 Chain tensioner (lower) 1
3 Bolt (rear shock absorber-relay
arm)1 Hold the swingarm.
4 Bolt (connecting rod) 1
5 Pivot shaft 1
6Swingarm
1
1

5 - 54
CHASSWINGARM
EC578000
SWINGARM DISASSEMBLY
Extent of removal:1 Swingarm disassembly2 Connecting rod removal and disassembly
3 Relay arm removal and disassembly
Extent of removal Order Part name Q’ty Remarks
SWINGARM DISASSEMBLY
1 Cap 2
2 Relay arm 1
3 Connecting rod 1
4 Collar 2
5 Oil seal 2
6 Thrust bearing 2
7 Bush 2
8 Oil seal 8
9 Bearing 8 Refer to “REMOVAL POINTS”.
1
3
2
23

5 - 55
CHASSWINGARM
EC573000
REMOVAL POINTS
EC573200
Bearing
1. Remove:
Bearing 1
NOTE:
Remove the bearing by pressing its outer race.
EC574010
INSPECTION
Wash the bearings, bushes, collars, and cov-
ers in a solvent.
EC574111
Swingarm
1. Inspect:
Bearing 1
Bush 2
Free play exists/unsmooth revolution/
rust → Replace bearing and bush as a
set.
2. Inspect:
Oil seal 3
Damage → Replace.
EC574210
Relay arm
1. Inspect:
Bearing 1
Collar 2
Free play exists/unsmooth revolution/
rust → Replace bearing and collar as a
set.
2. Inspect:
Oil seal 3
Damage → Replace.
EC574310
Connecting rod
1. Inspect:
Bearing 1
Collar 2
Free play exists/unsmooth revolution/
rust → Replace bearing and collar as a
set.
2. Inspect:
Oil seal 3
Damage → Replace.

5 - 56
CHASSWINGARM
EC575000
ASSEMBLY AND INSTALLATION
EC575201
Bearing and oil seal
1. Install:
Bearing 1
Oil seal 2
To swingarm.
NOTE:
Apply the molybdenum disulfide grease on
the bearing when installing.
Install the bearing by pressing it on the side
having the manufacture’s marks or numbers.
First install the outer and then the inner bear-
ings to a specified depth from inside.
Installed depth of bearings:
Outer a: Zero mm (Zero in)
Inner b: 8.5 mm (0.33 in)
2. Install:
Bearing 1
Oil seal 2
To relay arm.
NOTE:
Apply the molybdenum disulfide grease on
the bearing when installing.
Install the bearing by pressing it on the side
having the manufacture’s marks or numbers.
3. Install:
Bearing 1
Oil seal 2
To connecting rod.
NOTE:
Apply the molybdenum disulfide grease on
the bearing when installing.
Install the bearing by pressing it on the side
having the manufacture’s marks or numbers.
Installed depth of bearings a:
5 mm (0.20 in)
Installed depth of bearings a:
5 mm (0.20 in)

5 - 57
CHASSWINGARM
EC5751B1
Swingarm
1. Install:
Bush 1
Thrust bearing 2
Oil seal 3
Collar 4
To swingarm 5.
NOTE:
Apply the molybdenum disulfide grease on the
bushes, thrust bearings and oil seal lips.
2. Install:
Collar 1
To relay arm 2.
NOTE:
Apply the molybdenum disulfide grease on the
collars, bearings and oil seal lips.
3. Install:
Collar 1
To connecting rod 2.
NOTE:
Apply the molybdenum disulfide grease on the
collar, bearings and oil seal lips.
4. Install:
Connecting rod 1
Bolt (connecting rod) 2
Plain washer 3
Nut (connecting rod) 4
To relay arm 5.
NOTE:
Apply the molybdenum disulfide grease on the
bolt.
T R..80 Nm (8.0 m · kg, 58 ft · lb)

5 - 58
CHASSWINGARM
5. Install:
Relay arm 1
Bolt (relay arm) 2
Plain washer 3
Nut (relay arm) 4
To swingarm.
NOTE:
Apply the molybdenum disulfide grease on
the bolt.
Do not tighten the nut yet.
6. Install:
Swingarm 1
Pivot shaft 2
NOTE:
Apply the molybdenum disulfide grease on
the pivot shaft.
Insert the pivot shaft from right side.
T R..85 Nm (8.5 m · kg, 61 ft · lb)
7. Check:
Swingarm side play a
Free play exists → Replace thrust bear-
ing.
Swingarm up and down movement b
Unsmooth movement/binding/rough
spots → Grease or replace bearings,
bushes and collars.
8. Install:
Bolt (connecting rod) 1
Plain washer 2
Nut (connecting rod) 3
NOTE:
Apply the molybdenum disulfide grease on
the bolt.
Do not tighten the nut yet.
9. Install:
Bolt (rear shock absorber-relay arm) 1
Nut (rear shock absorber-relay arm) 2
NOTE:
Apply the molybdenum disulfide grease on the
bolt.
T R..53 Nm (5.3 m · kg, 38 ft · lb)

5 - 59
CHASSWINGARM
10. Tighten:
Nut (connecting rod) 1
T R..80 Nm (8.0 m · kg, 58 ft · lb)
11. Tighten:
Nut (relay arm) 1
T R..80 Nm (8.0 m · kg, 58 ft · lb)
12. Install:
Cap 1
NOTE:
Install the cap (right) with its mark a facing
forward.
13. Install:
Bolt [chain tensioner (lower)] 1
Plain washer 2
Collar 3
Chain tensioner 4
Nut [chain tensioner (lower)] 5
T R..20 Nm (2.0 m · kg, 14 ft · lb)
14. Install:
Chain support 1
Support cover 2
Bolt {chain support [r= 50 mm (1.97 in)]}
3
Nut (chain support) 4
Bolt {support cover [r= 10 mm (0.39 in)]}
5
T R..7 Nm (0.7 m · kg, 5.1 ft · lb)
T R..7 Nm (0.7 m · kg, 5.1 ft · lb)