relay YAMAHA YZ426F 2000 Owners Manual

SPEC
2 - 16
MAINTENANCE SPECIFICATIONS
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 brake reservoir tank and frame M6 ´ 1.0 1 10 1.0 7.2
Rear brake hose union bolt (caliper) M10 ´ 1.25 1 30 3.0 22
Rear brake hose union bolt (master cylinder)M10 ´ 1.25 1 30 3.0 22
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
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 26 2.6 19
Swingarm and brake hose holder M5 ´ – 4 4 0.4 2.9
Drive chain tensioner mounting M8 ´ 1.25 2 19 1.9 13
Chain support and swingarm M6 ´ 1.0 3 7 0.7 5.1
Seal guard and swingarm M5 ´ 0.8 4 4 0.4 2.9
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
Rear fender mounting M6 ´ 1.0 4 7 0.7 5.1

3 - 3
INSP
ADJ

MAINTENANCE INTERVALS
FRONT FORK OIL SEAL AND DUST
SEAL
Clean and lube
cc
Lithium base grease
REAR SHOCK ABSORBER
Inspect and adjust
Lube and retighten
c
cc
c
Lithium base grease
CHAIN GUARD AND ROLLERS
Inspect
cc
SWINGARM
Inspect and retighten
cc
RELAY ARM, CONNECTING ROD
Inspect and lube
cc
Lithium base grease
STEERING HEAD
Inspect free play and retighten
Clean and lube
Replace bearing
cc
c
c
Lithium base grease
TIRE, WHEELS
Inspect air pressure, wheel run-out,
tire wear and spoke looseness
Retighten sprocket bolt
Inspect bearings
Replace bearings
Lubricate
c
cc
c
c
cc
Lithium base grease
THROTTLE, CONTROL CABLE
Check routing and connection
Lubricate
c
cc
c
Yamaha cable lube or
SAE 10W-30 motor oil ItemAfter
break-inEvery
race
Every
third
(or
500 km)Every
fifth
(or
1,000 km)
As re-
quiredRemarks

5 - 51
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
2
2
3
3

5 - 50
CHASSWINGARM
EC570000
SWINGARM
Extent of removal:1 Swingarm removal
Extent of removal Order Part name Q’ty Remarks
STEERING REMOVAL
Refer to “FRONT BRAKE AND REAR
BRAKE” section.
Shift the brake pedal backward. Preparation for removal Hold the machine by placing the
suitable stand under the engine.
Brake hose holder
Rear caliper
Bolt (brake pedal)
Drive chain
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
6 Swingarm 1
WARNING
Support the machine securely so there is nodanger of it falling over.
1

5 - 52
CHASSWINGARM
EC573000
REMOVAL POINTS
EC573200
Bearing
1. Remove:
lBearing 1
NOTE:
Install the bearing by pressing its outer race.
EC574010
INSPECTION
Wash the bearings, bushes, collars, and cov-
ers in a solvent.
EC574111
Swingarm
1. Inspect:
lBearing 1
lBush 2
Free play exists/unsmooth revolution/
rust ® Replace bearing and bush as a
set.
2. Inspect:
lOil seal 3
Damage ® Replace.
EC574210
Relay arm
1. Inspect:
lBearing 1
lCollar 2
Free play exists/unsmooth revolution/rust
® Replace bearing and collar as a set.
2. Inspect:
lOil seal 3
Damage ® Replace.
EC574310
Connecting rod
1. Inspect:
lBearing 1
lCollar 2
Free play exists/unsmooth revolution/rust
® Replace bearing and collar as a set.
2. Inspect:
lOil seal 3
lDamage ® Replace.

5 - 53
CHASSWINGARM
EC575000
ASSEMBLY AND INSTALLATION
EC575201
Bearing and oil seal
1. Install:
lBearing 1
lOil seal 2
To swingarm.
NOTE:
lApply the molybdenum disulfide grease on
the bearing when installing.
lInstall the bearing by pressing it on the side
having the manufacture’s marks or numbers.
lFirst 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:
lBearing 1
lOil seal 2
To relay arm.
NOTE:
lApply the molybdenum disulfide grease on
the bearing when installing.
lInstall the bearing by pressing it on the side
having the manufacture’s marks or numbers.
3. Install:
lBearing 1
lOil seal 2
To connecting rod.
NOTE:
lApply the molybdenum disulfide grease on
the bearing when installing.
lInstall 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 - 54
CHASSWINGARM
EC5751A0
Swingarm
1. Install:
lBush 1
lThrust bearing 2
lCollar 3
To swingarm 4.
NOTE:
Apply the molybdenum disulfide grease on the
bushes, thrust bearings and oil seal lips.
2. Install:
lCollar 1
To relay arm 2.
NOTE:
Apply the molybdenum disulfide grease on the
collars, bearings and oil seal lips.
3. Install:
lCollar 1
To connecting rod 2.
NOTE:
Apply the molybdenum disulfide grease on the
collar, bearings and oil seal lips.
4. Install:
lConnecting rod 1
lBolt (connecting rod) 2
lPlain washer 3
lNut (connecting rod) 4
To relay arm 5.
T R..80 Nm (8.0 m · kg, 58 ft · lb)
NOTE:
Apply the molybdenum disulfide grease on the
bolt.
ACHTUNG:CAUTION:
Install the nut on the left side of the chas-
sis. If you make a mistake in its installation
position, the nut contacts the swingarm
when stroking the rear shock absorber.

5 - 55
CHASSWINGARM
5. Install:
lRelay arm 1
lBolt (relay arm) 2
lPlain washer 3
lNut (relay arm) 4
To swingarm.
NOTE:
lApply the molybdenum disulfide grease on
the bolt.
lDo not tighten the nut yet.
6. Install:
lSwingarm 1
lPivot shaft 2
NOTE:
lApply the molybdenum disulfide grease on
the pivot shaft.
lInsert the pivot shaft from right side.
T R..85 Nm (8.5 m · kg, 61 ft · lb)
7. Check:
lSwingarm side play a
Free play exists ® Replace thrust bear-
ing.
lSwingarm up and down movement b
Unsmooth movement/binding/rough
spots ® Grease or replace bearings,
bushes and collars.
8. Install:
lBolt (connecting rod) 1
lPlain washer 2
lNut (connecting rod) 3
NOTE:
lApply the molybdenum disulfide grease on
the bolt.
lDo not tighten the nut yet.
9. Install:
lPlain washer 1
lBolt (rear shock absorber-relay arm) 2
NOTE:
lApply the molybdenum disulfide grease on
the bolt.
lInsert the bolt from right side.
T R..53 Nm (5.3 m · kg, 38 ft · lb)

5 - 56
CHASSWINGARM
10. Tighten:
lNut (connecting rod) 1
T R..80 Nm (8.0 m · kg, 58 ft · lb)
11. Tighten:
lNut (relay arm) 1
T R..80 Nm (8.0 m · kg, 58 ft · lb)
12. Install:
lCap 1
NOTE:
Install the cap with its mark a facing forward.
13. Install:
lBolt [chain tensioner (lower)] 1
lPlain washer 2
lCollar 3
lChain tensioner 4
lNut [chain tensioner (lower)] 5
T R..19 Nm (1.9 m · kg, 13 ft · lb)
14. Install:
lChain support 1
lSupport cover 2
lBolt {chain support [r= 50 mm (1.97 in)]}
3
lNut (chain support) 4
lBolt {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)

5 - 57
CHASREAR SHOCK ABSORBER
EC580000
REAR SHOCK ABSORBER
Extent of removal:1 Rear shock absorber removal2 Rear shock absorber disassembly
Extent of removal Order Part name Q’ty Remarks
Preparation for removalREAR SHOCK ABSORBER
REMOVAL
Hold the machine by placing the
suitable stand under the engine.
Seat and fitting band Refer to “SAET, FUEL TANK AND SIDE
COVERS” section.
Silencer Refer to “EXHAUST PIPE AND
SILENCER” section.
1 Bolt (reservoir tank) 1
2 Clamp (air cleaner joint) 1Only loosening.
3 Rear frame 1
4 Bolt (rear shock absorber-relay
arm)1 Hold the swingarm.
5 Bolt (rear shock absorber-frame) 1
6 Rear shock absorber 1
7 Locknut 1Only loosening.
8 Adjuster 1Only loosening.
9 Spring guide (lower) 1
WARNING
Support the machine securely so there is nodanger of it falling over.
1
2