2008 YAMAHA YZ450F wheel torque

CONTENTS
CHAPTER 1
GENERAL INFOR-
MATION
DESCRIPTION ................. 1-1
MACHINE
IDENTIFICATION ............ 1-2
INCLUDED PARTS .......... 1-2
IMPORTANT
INFORMATION................. 1-2
CHECKING OF CONNEC-
TION ................................. 1-3
SPECIAL TOOLS ............. 1-4
CONTROL FUNCTIONS .. 1-8
STARTING AND
BREAK-IN ........................ 1-8
TORQUE-CHECK
POINTS........................... 1-11
CLEANING AND
STORAGE ...................... 1-12
CHAPTER 2
SPECIFICATIONS
GENERAL SPECIFICA-
TIONS ............................... 2-1
MAINTENANCE SPECIFICA-
TIONS ............................... 2-3
TIGHTENING
TORQUES ...................... 2-10
LUBRICATION
DIAGRAMS .................... 2-16
CABLE ROUTING
DIAGRAM ....................... 2-18
CHAPTER 3
REGULAR INSPEC-
TION AND AD-
JUSTMENTS
MAINTENANCE
INTERVALS...................... 3-1PRE-OPERATION
INSPECTION AND MAINTE-
NANCE ............................. 3-4
ENGINE ............................ 3-5
CHASSIS ........................ 3-13
ELECTRICAL ................. 3-22
CHAPTER 4
ENGINE
SEAT, FUEL TANK AND
SIDE COVERS.................. 4-1
EXHAUST PIPE AND
SILENCER ........................ 4-3
RADIATOR ....................... 4-5
CARBURETOR................. 4-7
CAMSHAFTS.................. 4-14
CYLINDER HEAD........... 4-19
VALVES AND VALVE
SPRINGS ........................ 4-22
CYLINDER AND
PISTON ........................... 4-26
CLUTCH ......................... 4-29
OIL FILTER ELEMENT
AND WATER PUMP ....... 4-33
BALANCER .................... 4-37
OIL PUMP ....................... 4-39
KICK SHAFT AND SHIFT
SHAFT ............................ 4-42
CDI MAGNETO............... 4-47
ENGINE REMOVAL ....... 4-49
CRANKCASE AND CRANK-
SHAFT ............................ 4-53
TRANSMISSION, SHIFT
CAM AND SHIFT FORK. 4-59
CHAPTER 5
CHASSIS
FRONT WHEEL AND REAR
WHEEL ............................. 5-1
FRONT BRAKE AND REAR
BRAKE ............................. 5-6
FRONT FORK................. 5-16
HANDLEBAR ................. 5-24STEERING ......................5-28
SWINGARM ....................5-32
REAR SHOCK
ABSORBER ....................5-37
CHAPTER 6
ELECTRICAL
ELECTRICAL COMPO-
NENTS AND WIRING DIA-
GRAM ...............................6-1
IGNITION SYSTEM...........6-2
THROTTLE POSITION SEN-
SOR SYSTEM ...................6-5
CHAPTER 7
TUNING
ENGINE.............................7-1
CHASSIS ..........................7-6

1-11
TORQUE-CHECK POINTS
TORQUE-CHECK POINTS
Concerning the tightening torque, refer to "TIGHTENING TORQUES" section in the CHAPTER 2.
Frame construction Frame to rear frame
Combined seat and fuel tank Fuel tank to frame
Exhaust system Silencer to rear frame
Engine mounting Frame to engine
Engine bracket to engine
Engine bracket to frame
Steering Steering stem to handlebar Steering stem to frame
Steering stem to upper bracket
Upper bracket to handlebar
Suspension Front Steering stem to front fork Front fork to upper bracket
Front fork to lower bracket
Rear For link type Assembly of links
Link to frame
Link to rear shock absorber
Link to swingarm
Installation of rear shock absorber Rear shock absorber to frame
Installation of swingarm Tightening of pivot shaft
Wheel Installation of wheel Front Tightening of wheel axle
Tightening of axle holder
Rear Tightening of wheel axle
Wheel to rear wheel sprocket
Brake Front Brake caliper to front fork
Brake disc to wheel
Tightening of union bolt
Brake master cylinder to handlebar
Tightening of bleed screw
Tightening of brake hose holder
Rear Brake pedal to frame
Brake disc to wheel
Tightening of union bolt
Brake master cylinder to frame
Tightening of bleed screw
Tightening of brake hose holder
Fuel system Fuel tank to fuel cock
Lubrication system Tightening of oil hose clamp

2-11
TIGHTENING TORQUES
Throttle cable (return) M12 × 1.0 1 11 1.1 8.0
Throttle cable cover M5 × 0.8 2 4 0.4 2.9
Hot starter plunger M12 × 1.0 1 2 0.2 1.4
Hot starter cable adjust bolt and locknut M6 × 0.75 1 4 0.4 2.9
Air filter element M6 × 1.0 1 2 0.2 1.4
Radiator stay M6 × 1.0 6 7 0.7 5.1
Radiator M6 × 1.0 4 10 1.0 7.2
Radiator hose clamp M6 × 1.0 8 2 0.2 1.4
Radiator pipe 1, 2 M6 × 1.0 2 10 1.0 7.2
Impeller M8 × 1.25 1 14 1.4 10
Water pump housing cover M6 × 1.0 3 10 1.0 7.2
Coolant drain bolt M6 × 1.0 1 10 1.0 7.2
Oil pump cover M4 × 0.7 1 2 0.2 1.4
Oil pump M6 × 1.0 2 10 1.0 7.2
Oil pump drive gear shaft M6 × 1.0 1 10 1.0 7.2
Oil filter element drain bolt M6 × 1.0 1 10 1.0 7.2
Oil filter element cover M6 × 1.0 2 10 1.0 7.2
Oil pressure check bolt M6 × 1.0 1 10 1.0 7.2
△Oil hose clamp — 2 2 0.2 1.4
Crankshaft end accessing screw M27 × 1.5 1 10 1.0 7.2
Timing mark accessing screw M14 × 1.5 1 6 0.6 4.3
Clutch cover M6 × 1.0 7 10 1.0 7.2
Right crankcase cover M6 × 1.0 8 10 1.0 7.2
Right crankcase cover M6 × 1.0 2 12 1.2 8.7
Left crankcase cover M6 × 1.0 8 10 1.0 7.2
Crankcase M6 × 1.0 12 12 1.2 8.7
Clutch cable holder M6 × 1.0 2 10 1.0 7.2
Oil drain bolt (right crankcase) M10 × 1.25 1 20 2.0 14
Oil drain bolt (left crankcase) M8 × 1.25 1 20 2.0 14
Oil check bolt (crankcase) M6 × 1.0 1 10 1.0 7.2
Oil strainer M6 × 1.0 1 10 1.0 7.2
Crankcase bearing stopper M6 × 1.0 8 10 1.0 7.2
Crankcase bearing stopper (crankshaft) M6 × 1.0 4 14 1.4 10
Drive axle oil seal stopper M6 × 1.0 2 10 1.0 7.2
Kick shaft ratchet wheel guide M6 × 1.0 2 12 1.2 8.7
Kickstarter crank M8 × 1.25 1 33 3.3 24
Screw (kickstarter crank) M6 × 1.0 1 7 0.7 5.1
Primary drive gear M20 × 1.0 1 110 11.0 80
Clutch boss M20 × 1.0 1 75 7.5 54
Clutch cable adjust bolt and locknut M6 × 0.75 1 4 0.4 2.9
Clutch spring M6 × 1.0 6 10 1.0 7.2
Balancer M10 × 1.0 1 45 4.5 32
Balancer shaft driven gear M14 × 1.0 1 50 5.0 36
Balancer weight M6 × 1.0 3 10 1.0 7.2Part to be tightened Thread size Q'tyTightening torque
Nm m•kg ft•lb

2-13
TIGHTENING TORQUES
△Front wheel axle and axle nut M16 × 1.5 1 105 10.5 75
△Front wheel axle holder M8 × 1.25 4 21 2.1 15
△Front brake disc and wheel hub M6 × 1.0 6 12 1.2 8.7
△Rear brake disc and wheel hub M6 × 1.0 6 14 1.4 10
△Footrest bracket and frame M10 × 1.25 4 55 5.5 40
△Brake pedal mounting M8 × 1.25 1 26 2.6 19
△Rear brake master cylinder and frame 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 (brake caliper) M10 × 1.25 1 30 3.0 22
△Rear brake hose union bolt (brake master cylinder) M10 × 1.25 1 30 3.0 22
△Rear wheel axle and axle 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 10 1.0 7.2
△Protector and rear brake caliper M6 × 1.0 2 7 0.7 5.1
Drive chain puller adjust bolt and locknut M8 × 1.25 2 19 1.9 13
Engine mounting:
△Upper engine bracket and frame M10 × 1.25 4 55 5.5 40
△Lower engine bracket and frame M8 × 1.25 4 34 3.4 24
△Engine and engine bracket (front) M10 × 1.25 1 53 5.3 38
△Engine and engine bracket (upper) M10 × 1.25 1 55 5.5 40
△Engine and frame (lower) M10 × 1.25 1 53 5.3 38
△Engine guard M6 × 1.0 1 10 1.0 7.2
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 CDI unit bracket M5 × 0.8 2 4 0.4 2.9
Cable guide and frame M5 × 0.8 1 5 0.5 3.6
△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 and frame (upper) M8 × 1.25 1 38 3.8 27
△Rear frame and frame (lower) M8 × 1.25 2 32 3.2 23
△Swingarm and brake hose holder M5 × 0.8 4 2 0.2 1.4
Swingarm and patch M4 × 0.7 4 2 0.2 1.4
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 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 boss and frame M10 × 1.25 1 20 2.0 14
△Fuel tank mounting M6 × 1.0 2 9 0.9 6.5
△Fuel tank and fuel cock M6 × 1.0 2 4 0.4 2.9Part to be tightened Thread size Q'tyTightening torque
Nm m•kg ft•lb