2010 YAMAHA YZ250F relay

2-13
TIGHTENING TORQUES
△Front brake disc M6 × 1.0 6 12 1.2 8.7
△ Rear brake disc M6 × 1.0 6 14 1.4 10
△ Footrest bracket and frame M10 × 1.25 4 55 5.5 40
△ Brake pedal M8 × 1.25 1 26 2.6 19
△ Rear brake master cylinder M6 × 1.0 2 10 1.0 7.2
Rear brake master cylinder cap M4 × 0.7 2 2 0.2 1.4
△ Rear brake hose union bolt M10 × 1.25 2 30 3.0 22
△ Rear wheel axle and axle nut M22 × 1.5 1 135 13.5 98
△ 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 10 1.0 7.2
△ Rear brake caliper protector M6 × 1.0 2 7 0.7 5.1
Drive chain puller adjust bolt and locknut M8 × 1.25 2 21 2.1 15
Engine mounting:
△ Engine and engine bracket (front) M10 × 1.25 1 53 5.3 38
△ Engine and frame (lower) M10 × 1.25 1 53 5.3 38
△ Upper engine bracket and frame M8 × 1.25 4 34 3.4 25
△ Front engine bracket and frame M8 × 1.25 4 34 3.4 25
△ Engine and engine bracket (upper) M10 × 1.25 2 55 5.5 40
Lower engine guard M6 × 1.0 3 10 1.0 7.2
CDI unit bracket M6 × 1.0 2 7 0.7 5.1
Cable guide and frame M6 × 1.0 2 7 0.7 5.1
△ Pivot shaft and nut M16 × 1.5 1 85 8.5 61
△ Relay arm and swingarm M14 × 1.5 1 70 7.0 50
△ 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 2 32 3.2 23
△ Rear frame (lower) M8 × 1.25 2 32 3.2 23
△ Swingarm and brake hose holder M5 × 0.8 4 3 0.3 2.2
Upper drive chain tensioner M8 × 1.25 1 16 1.6 11
Lower drive chain tensioner M8 × 1.25 1 16 1.6 11
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 1 9 0.9 6.5
△ Fuel cock M6 × 1.0 2 4 0.4 2.9
Seat set bracket and fuel tank M6 × 1.0 1 7 0.7 5.1
Fuel tank bracket and fuel tank M6 × 1.0 2 7 0.7 5.1
Side cover set bracket and fuel tank M6 × 1.0 2 7 0.7 5.1
Fitting band set screw and fuel tank M6 × 1.0 1 7 0.7 5.1
△ Air scoop and fuel tank M6 × 1.0 2 7 0.7 5.1
△ Air scoop and radiator guard M6 × 1.0 4 7 0.7 5.1
Air scoop and frame M6 × 1.0 2 7 0.7 5.1
Part to be tightened
Thread size Q'tyTightening torque
Nm m•kg ft•lb

3-4
MAINTENANCE INTERVALS
REAR SHOCK ABSORBERInspect and adjust ●●
Lube ●(After
rain
ride) ●Molybdenum disulfide grease
Replace spring seat ●Every one year
Retighten ●●
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 ●Lithium base grease
Replace bearing ●
TIRE, WHEELS Inspect air pressure, wheel run-
out, tire wear and spoke loose-
ness ●●
Retighten sprocket bolt ●●
Inspect bearings ●
Replace bearings ●
Lubricate ●Lithium base grease
THROTTLE, CONTROL CABLE Check routing and connection ●●
Lubricate ●● Yamaha cable lube or SAE 10W-40
motor oil
Inspect and clean (throttle ca-
ble) ●●
Inspect dirt and wear on the throttle
cable on the carburetor side.
HOT STARTER, CLUTCH LEVER Inspect free play ●
Item
After
break- in Every
race
(about 2.5
hours)
Every third
(about 7.5
hours) Every
fifth
(about 12.5
hours)
As re-
quired Remarks

5-31
SWINGARM
SWINGARM
REMOVING THE SWINGARMOrder Part name Q'ty Remarks Hold the machine by placing the suitable stand
under the engine. Refer to "HANDLING NOTE".
Brake hose holder Refer to "FRONT BRAKE AND REAR
BRAKE" section.
Rear brake caliper Refer to "FRONT BRAKE AND REAR
BRAKE" section.
Bolt (brake pedal) Shift the brake pedal backward.
Drive chain
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

5-32
SWINGARM
DISASSEMBLING THE SWINGARMOrder Part name Q'ty Remarks1 Relay arm 1
2 Connecting rod 1
3 Collar 2
4 Oil seal 2
5 Thrust bearing 2
6 Bushing 2
7 Oil seal 8
8 Bearing 10 Refer to removal section.

5-33
SWINGARM
HANDLING NOTE
Support the machine securely so
there is no danger of it falling over.
REMOVING THE BEARING
1. Remove:• Bearing "1"
Remove the bearing by pressing its
outer race.
CHECKING THE SWINGARM
1. Inspect:• Bearing "1"
• Bushing "2"
Free play exists/unsmooth revolu-
tion/rust →Replace bearing and
bushing as a set.
2. Inspect: • Oil seal "3"Damage →Replace.
CHECKING THE RELAY ARM
1. 5294Inspect: • Bearing "1"
•Collar "2"
Free play exists/unsmooth revolu-
tion/rust → Replace bearing and
collar as a set.
2. Inspect: • Oil seal "3"Damage →Replace. CHECKING THE CONNECTING
ROD
1. Inspect:
•Bearing "1"
• Collar "2"Free play exists/unsmooth revolu-
tion/rust → Replace bearing and
collar as a set.
2. Inspect: • Oil seal "3"
Damage →Replace.
INSTALLING THE BEARING AND
OIL SEAL
1. Install: •Bearing "1"
• Oil seal "2"To swingarm.
• Apply the molybdenum disulfide
grease on the bearing when install-
ing.
• Install the bearing by pressing it on
the side having the manufacture's
marks or numbers.
• First install the outer and then the
inner bearings to a specified depth
from inside.
2. Install: • Bearing "1"
• Washer "2"
• Oil seal "3"To relay arm.
• Apply the molybdenum disulfide grease on the bearing when install-
ing.
• Install the bearing by pressing it on the side having the manufacture's
marks or numbers.
• Apply the molybdenum disulfide grease on the washer.
3. Install:• Bearing "1"
• Oil seal "2"To connecting rod.
• Apply the molybdenum disulfide grease on the bearing when install-
ing.
• Install the bearing by pressing it on the side having the manufacture's
marks or numbers.
Installed depth of bear-
ings:
Outer "a": Zero mm
(Zero in)
Inner "b": 6.5 mm (0.26
in)
Installed depth of bear-
ings "a": Zero mm (Zero in)
Installed depth of bear-
ings "a": Zero mm (Zero in)

5-34
SWINGARM
INSTALLING THE SWINGARM
1. Install:• Bushing "1"
• Thrust bearing "2"
• Oil seal "3"
•Collar "4"To swingarm "5".
Apply the molybdenum disulfide
grease on the bushings, thrust bear-
ings, oil seal lips and contact surfaces
of the collar and thrust bearing.
2. Install:•Collar "1"
• Washer "2"
To relay arm "3".
Apply the molybdenum disulfide
grease on the collars and oil seal lips.
3. Install:•Collar "1"To connecting rod "2".
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".
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.
• Apply the molybdenum disulfide
grease on the bolt circumference
and threaded portion.
• Do not tighten the nut yet.
6. Install: • Swingarm "1"
• Pivot shaft "2"
• 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
bearing.
• Swingarm up and down move- ment "b"
Unsmooth movement/binding/
rough spots →Grease or replace
bearings, bushings and collars. 8. Install:
• Bolt (connecting rod) "1"
• Washer "2"
• Nut (connecting rod) "3"
• 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"
Apply the molybdenum disulfide
grease on the bolt.
10. Tighten:• Nut (connecting rod) "1"
Nut (connecting rod): 80 Nm (8.0 m•kg, 58
ft•lb)
Pivot shaft:85 Nm (8.5 m•kg, 61
ft•lb)
Nut (rear shock absorb-
er-relay arm): 53 Nm (5.3 m•kg, 38
ft•lb)
Nut (connecting rod): 80 Nm (8.0 m•kg, 58
ft•lb)

5-35
SWINGARM
11. Tighten:• Nut (relay arm) "1"
12. Install: • Bolt (lower chain tensioner) "1"
• Washer "2"
•Collar "3"
• Lower chain tensioner "4"
• Nut (lower chain tensioner) "5"
13. Install: • Drive chain support "1"
• Drive chain support cover "2"
• Bolt {drive chain support [L = 50 mm (1.97 in)]} "3"
• Nut (drive chain support) "4"
• Bolt {drive chain support cover [L
= 10 mm (0.3 9 in)]} "5"
Nut (relay arm):
70 Nm (7.0 m•kg, 50
ft•lb)
Nut (lower chain tension-
er): 16 Nm (1.6 m•kg, 11
ft•lb)
Nut (drive chain sup-
port): 7 Nm (0.7 m•kg, 5.1
ft•lb)
Bolt (drive chain support
cover): 7 Nm (0.7 m•kg, 5.1
ft•lb)

5-36
REAR SHOCK ABSORBER
REAR SHOCK ABSORBER
REMOVING THE REAR SHOCK ABSORBEROrder Part name Q'ty Remarks Hold the machine by placing the suitable stand
under the engine. Refer to "HANDLING NOTE".
Seat Refer to "SEAT, FUEL TANK AND SIDE
COVERS" section in the CHAPTER 4.
Silencer Refer to "EXHAUST PIPE AND SILENCER"
section in the CHAPTER 4.
1 Clamp (air filter joint) 1 Only loosening.
2Rear frame 1
3 Bolt (rear shock absorber-relay arm) 1 Hold the swingarm.
4 Bolt (rear shock absorber-frame) 1
5 Rear shock absorber 1
6 Locknut 1 Only loosening.
7 Adjuster 1 Only loosening.
8 Lower spring guide 1
9 Upper spring guide 1
10 Spring (rear shock absorber) 1
11 Bearing 2 Refer to removal section.
B2
9
8
10
11
11