2003 YAMAHA YZ250F relay

SPEC
2 - 15
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
Nipple (spoke)—72 3 0.3 2.2
Rear wheel sprocket M8 × 1.25 6 42 4.2 30
Rear brake disc cover M6 × 1.0 2 7 0.7 5.1
Rear brake caliper protector M6 × 1.0 2 7 0.7 5.1
Drive chain puller adjust bolt and locknut M8 × 1.25 2 16 1.6 11
Engine mounting:
Engine and engine bracket (front) M10 × 1.25 1 69 6.9 50
Engine and frame (lower) M10 × 1.25 1 69 6.9 50
Engine bracket and frame M8 × 1.25 6 34 3.4 24
Engine and engine bracket (upper) M10 × 1.25 1 55 5.5 40
Lower engine guard M6 × 1.0 3 10 1.0 7.2
Right engine guard M8 × 1.25 2 23 2.3 17
CDI unit bracket M6 × 1.0 1 10 1.0 7.2
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 (upper) M8 × 1.25 1 32 3.2 23
Rear frame (lower) M8 × 1.25 2 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
Upper drive chain tensioner M8 × 1.25 1 19 1.9 13
Lower drive chain tensioner M8 × 1.25 1 20 2.0 14
Drive chain support M6 × 1.0 3 7 0.7 5.1
Seal guard and swingarm M5 × 0.8 4 6 0.6 4.3
Fuel tank M6 × 1.0 2 10 1.0 7.2
Fuel cock M6 × 1.0 2 7 0.7 5.1
Seat set bracket and fuel tank M6 × 1.0 1 7 0.7 5.1
Hooking screw (fitting band) and fuel tank M6 × 1.0 1 7 0.7 5.1
Radiator cover M6 × 1.0 6 4 0.4 2.9
Front fender M6 × 1.0 4 7 0.7 5.1
Rear fender (front) M6 × 1.0 2 7 0.7 5.1
Rear fender (rear) M6 × 1.0 2 10 1.0 7.2
Side cover M6 × 1.0 2 7 0.7 5.1
Seat M8 × 1.25 2 23 2.3 17
Number plate M6 × 1.0 1 7 0.7 5.1

3 - 3
INSP
ADJ
MAINTENANCE INTERVALS
FRONT 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
DRIVE CHAIN GUIDE 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.
HOT STARTER, CLUTCH LEVER
Inspect free play
●
ItemAfter
break-inEvery
race
Every
third
(or
500 km)Every
fifth
(or
1,000 km)As re-
quiredRemarks

5 - 50
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 brake caliper
Bolt (brake pedal)
Drive chainRefer to “FRONT BRAKE AND REAR
BRAKE” section.
Shift the brake pedal backward.
1 Drive chain support 1
2 Lower chain tensioner 1
3 Bolt (rear shock absorber-relay
arm)1 Hold the swingarm.
4 Bolt (connecting rod) 1
5 Pivot shaft 1
6 Swingarm 1
1

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 Bushing 2
8 Oil seal 8
9 Bearing 8 Refer to “REMOVAL POINTS”.
1
2
32
3

5 - 52
CHASSWINGARM
EC573000
REMOVAL POINTS
EC573200
Bearing
1. Remove:
Bearing 1
NOTE:
Remove the bearing by pressing its outer race.
INSPECTION
Wash the bearings, bushings, collars, and cov-
ers in a solvent.
Swingarm
1. Inspect:
Bearing 1
Bushing 2
Free play exists/unsmooth revolution/
rust → Replace bearing and bushing as
a set.
2. Inspect:
Oil seal 3
Damage → Replace.
EC574210
Relay arm
1. Inspect:
Bearing (polylube bearing) 1
Collar 2
Free play exists/unsmooth revolution/rust
→ Replace bearing and collar as a set.
2. Inspect:
Bearing (polylube bearing) 1
Loss of solid lubrication → Replace.
Oil seal 3
Damage → Replace.
NOTE:
Polylube bearings, with solid lubrication, have
been adopted with the intent to make the nee-
dle bearings, used in this model, maintenance
free. With polylube bearings, no grease nipple
and regular lubrication is necessary. However,
grease should be applied to all oil seals and
collars when removed or installed.

5 - 54
CHASSWINGARM
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)
Swingarm
1. Install:
Bushing 1
Thrust bearing 2
Oil seal 3
Collar 4
To swingarm 5.
NOTE:
Apply the molybdenum disulfide grease on the
bushings, thrust bearings and oil seal lips.
2. Install:
Collar 1
To relay arm 2.
NOTE:
Apply the molybdenum disulfide grease on the
collars and oil seal lips.

5 - 55
CHASSWINGARM
3. Install:
Collar 1
To connecting rod 2.
NOTE:
Apply the molybdenum disulfide grease on the
collar and oil seal lips.
4. Install:
Connecting rod 1
Bolt (connecting rod) 2
Washer 3
Nut (connecting rod) 4
To relay arm 5.
NOTE:
Apply the molybdenum disulfide grease on the
bolt.
5. Install:
Relay arm 1
Bolt (relay arm) 2
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.
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,
bushings and collars.
T R..80 Nm (8.0 m · kg, 58 ft · lb)
T R..85 Nm (8.5 m · kg, 61 ft · lb)

5 - 56
CHASSWINGARM
8. Install:
Bolt (connecting rod) 1
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)
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 right cap with its mark a facing for-
ward.