steering wheel YAMAHA YZ450F 2015 Owners Manual

TORQUE-CHECK POINTS
1-25
EAS1SL5049
TORQUE-CHECK POINTS
Frame construction Frame to rear frame
Frame to engine protector
Combined seat and fuel tank Fuel tank to frame
Engine mounting Frame to engine
Engine bracket to engine
Engine bracket to frame
Seat Seat 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 Link Assembly of links
Link to frame
Link to rear shock absorber
Link to swingarm
Mounting of rear shock absorber Rear shock absorber and frame
Mounting of swingarm Tightening of pivot shaft
Wheel (s) Mounting of wheel Front Tightening of wheel axle
Tightening of axle holder
Tightening of spoke nipple
Rear Tightening of wheel axle
Wheel to rear wheel sprocket
Tightening of spoke nipple
Brake(s) Front Brake caliper to front fork
Brake disc to wheel
Tightening of union bolt
Brake master cylinder to handle-
bar
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 pump to fuel tank
Plastic cover Tightening of number plate

TIGHTENING TORQUES
2-18
EAS1SL5059CHASSIS TIGHTENING TORQUES
TIP
- marked portion shall be checked for torque tightening after break-in or before each race.
ITEMThread
sizeQ’ty TIGHTENING TORQUES Remarks
Outer tube and upper bracket bolt M8 4 21 Nm (2.1 m·kgf, 15 ft·lbf)
Outer tube and lower bracket bolt M8 4 21 Nm (2.1 m·kgf, 15 ft·lbf)
Upper bracket and steering stem nut M24 1 145 Nm (14.5 m·kgf, 105 ft·lbf)
Upper handlebar holder bolt M8 4 28 Nm (2.8 m·kgf, 20 ft·lbf)
Lower handlebar holder nut M10 2 40 Nm (4.0 m·kgf, 29 ft·lbf)
Engine stop switch screw M3 1 0.5 Nm (0.05 m·kgf, 0.36 ft·lbf)
Lower ring nut M28 1 See TIP.
Outer tube and damper assembly M51 2 30 Nm (3.0 m·kgf, 22 ft·lbf)
Inner tube and adjuster M22 2 55 Nm (5.5 m·kgf, 40 ft·lbf)
Damper assembly and base valve M42 2 28 Nm (2.8 m·kgf, 20 ft·lbf)
Damper assembly adjuster M12 2 29 Nm (2.9 m·kgf, 21 ft·lbf)
Bleed screw (front fork) and base
valveM5 2 1.3 Nm (0.13 m·kgf, 0.94 ft·lbf)
Front fork protector bolt M6 6 5 Nm (0.5 m·kgf, 3.6 ft·lbf)
Front fork protector and brake hose
holder boltM6 2 9 Nm (0.9 m·kgf, 6.5 ft·lbf)
Throttle grip cap screw M5 2 3.8 Nm (0.38 m·kgf, 2.8 ft·lbf)
Clutch lever holder bolt M6 2 5 Nm (0.5 m·kgf, 3.6 ft·lbf)
Clutch lever nut M6 1 4.0 Nm (0.40 m·kgf, 2.9 ft·lbf)
Clutch lever position locknut M5 1
4.8 Nm (0.48 m·kgf, 3.5 ft·lbf)
Front brake master cylinder holder
boltM6 2 9 Nm (0.9 m·kgf, 6.5 ft·lbf)
Front brake master cylinder reser-
voir cap screwM4 2 1.5 Nm (0.15 m·kgf, 1.1 ft·lbf)
Front brake lever pivot bolt M6 1 6 Nm (0.6 m·kgf, 4.3 ft·lbf)
Front brake lever pivot nut M6 1 6 Nm (0.6 m·kgf, 4.3 ft·lbf)
Front brake lever position locknut M6 1 5 Nm (0.5 m·kgf, 3.6 ft·lbf)
Front brake hose holder and lower
bracket boltM6 1 9 Nm (0.9 m·kgf, 6.5 ft·lbf)
Front brake hose union bolt M10 2 30 Nm (3.0 m·kgf, 22 ft·lbf)
Front brake caliper bolt M8 2 28 Nm (2.8 m·kgf, 20 ft·lbf)
Front brake pad pin M10 1 17 Nm (1.7 m·kgf, 12 ft·lbf)
Front brake pad pin plug M10 1 2.5 Nm (0.25 m·kgf, 1.8 ft·lbf)
Front brake caliper bleed screw M8 1 6 Nm (0.6 m·kgf, 4.3 ft·lbf)
Front wheel axle nut M18 1 115 Nm (11.5 m·kgf, 83 ft·lbf)
Front wheel axle pinch bolt M8 4 21 Nm (2.1 m·kgf, 15 ft·lbf)
LT

LUBRICATION POINTS AND LUBRICANT TYPES
2-23
EAS1SL5062CHASSIS
Lubrication point Lubricant types
Upper bearings (steering head)
Upper bearings and bearing race cover (steering head)
Lower bearings and oil seal lip (steering head)
Steering stem threads and nut contacting surface
Pivot shaft bearing
Swingarm pivot portion (collar side surface and thrust bearing)
Swingarm pivot portion (collar outer surface)
Swingarm pivot portion (oil seal lip)
Pivot shaft outer surface
Relay arm bearing and oil seal lip
Relay arm thrust washer surface (both sides)
Relay arm collar outer surface and bolt outer surface
Relay arm bolt threads (swingarm side)
Connecting arm bearing and oil seal lip
Connecting arm collar outer surface and bolt outer surface
Rear shock absorber assembly collar outer surface and dust seal lip (upper
side)
Rear shock absorber assembly bearing and dust seal lip (lower side)
Brake pedal pivot portion (O-ring and bolt outer surface)
Front wheel oil seal lip
Front wheel axle outer surface
Rear wheel oil seal lip
Rear wheel axle outer surface
Push rod contacting portion (front brake master cylinder)
Front brake lever bolt outer surface
Clutch lever sliding surface and bolt outer surface
Clutch lever position adjuster end
Clutch lever adjuster rubber lip
Clutch cable end (clutch lever side)
Tube guide (throttle grip) inner surface and throttle cable end
Front brake caliper piston
Front brake caliper piston seal
Front brake caliper dust seal
Front brake caliper piston outer surface
Front brake caliper pin bolt and boot
Front brake master cylinder push rod end
Front brake master cylinder kit
Rear brake caliper piston
Rear brake caliper piston seal
LS
LS
LS
LS
M
M
M
M
M
M
M
M
M
M
M
M
M
LS
LS
LS
LS
LS
S
S
LS
LS
LS
LS
LS
S
S
S
S
S

CHECKING THE WHEEL BEARINGS ..................................................... 3-33
CHECKING AND ADJUSTING THE STEERING HEAD .......................... 3-33
LUBRICATING THE LEVERS .................................................................. 3-34
LUBRICATING THE PEDAL .................................................................... 3-34
ELECTRICAL SYSTEM.................................................................................. 3-35
CHECKING THE SPARK PLUG .............................................................. 3-35
CHECKING THE IGNITION TIMING ........................................................ 3-35

MAINTENANCE INTERVALS
3-5
Replace brake flu-
idEvery one year
SWINGARM
Inspect, lube and
retightenMolybdenum disulfide grease
RELAY ARM, CON-
NECTING ROD
Inspect, lube and
retightenMolybdenum disulfide grease
STEERING HEAD
Inspect free play
and retightenCheck for tightening torques.
Clean and lube After rain ride
Replace bearings
TIRE, WHEELS
Inspect air pres-
sure, wheel run-
out, tire wear and
spoke looseness
Retighten sprocket
bolt
Check the bearing
Replace bearings
Lubricate Lithium soap base grease
DRIVE CHAIN Use chain oil.
Clean, lubricate,
slack, alignment
Replace
DRIVE CHAIN
GUIDE
Inspect Inspect wear.
DRIVE CHAIN
GUIDE AND DRIVE
CHAIN SUPPORT
Replace
CABLES
Routing (Connec-
tion)
Check and grease
Check and clean
throttle cableCheck throttle cables on the
throttle body for dirt and wear. ITEMAfter
break-
inEvery
race
(about
2.5
hours)Every
third
(about
7.5
hours)Every
fifth
(about
12.5
hours)As re-
quiredRemarks

PRE-OPERATION INSPECTION AND MAINTENANCE
3-7
EAS1SL5068
PRE-OPERATION INSPECTION AND MAINTENANCE
Before riding for break-in operation, practice or a race, make sure the machine is in good operating
condition.
Before using this machine, check the following points.
EAS1SL5069GENERAL INSPECTION AND MAINTENANCE
TIP
Perform usual maintenance enough so that, in the race course, a confirmation of that and simple set-
ting adjustments may only be left, in order to get enough time to use effectively.ITEM inspect Page
CoolantCheck that coolant is filled up to the radiator cap.
Check the cooling system for leakage.3-8 – 10
FuelCheck that a fresh gasoline is filled in the fuel tank.
Check the fuel line for leakage.1-22
Engine oilCheck that the oil level is correct. Check the crank-
case and oil line for leakage.3-14 – 16
Gear shifter and clutchCheck that gears can be shifted correctly in order and
that the clutch operates smoothly.3-10 – 11
Throttle grip/HousingCheck that the throttle grip operation and free play
are correctly adjusted. Lubricate the throttle grip and
housing, if necessary.3-11 – 12
BrakesCheck the play of front brake and effect of front and
rear brake.3-21 – 27
Drive chainCheck drive chain slack and alignment. Check that
the drive chain is lubricated properly.3-27
4-64 – 65
WheelsCheck for excessive wear and tire pressure. Check
for loose spokes and have no excessive play.3-32 – 33
SteeringCheck that the handlebar can be turned smoothly and
have no excessive play.3-33 – 34
Front forks and rear
shock absorberCheck that they operate smoothly and there is no oil
leakage.3-28 – 32
Cables (wires)Check that the clutch and throttle cables move
smoothly. Check that they are not caught when the
handlebars are turned or when the front forks travel
up and down.—
Exhaust pipeCheck that the exhaust pipe is tightly mounted and
has no cracks.3-13 – 14
Rear wheel sprocketCheck that the rear wheel sprocket tightening bolt is
not loose.4-8 – 9
Lubrication Check for smooth operation. Lubricate if necessary. 3-12 , 3-34
Bolts and nutsCheck the chassis and engine for loose bolts and
nuts.1-25 – 26
Lead connectorsCheck that the AC magneto, ECU and ignition coil are
connected tightly.1-12 – 14
SettingsIs the machine set suitably for the condition of the rac-
ing course and weather or by taking into account the
results of test runs before racing? Are inspection and
maintenance completely done?10-1 – 8

CHASSIS
3-33
2. Tighten:
• Spokes
Use a spoke nipple wrench “1” for tighten-
ing.
TIP
• Do not give a half turn (180 °) or more for one
tightening.
• Make sure that tightening after a break-in is
done until the initial looseness in nipples dis-
appears.
• Make sure that tightening is done in stages,
not at a time.
EAS1SL5110CHECKING THE WHEELS
1. Check:
• Wheel (s)
Damage/out-of-round  Replace.
EWA13260
WARNING
Never attempt to make any repairs to the
wheel.
TIP
After replacing a tire or a wheel, always bal-
ance the wheel.
EAS1SL5111CHECKING THE WHEEL BEARINGS
1. Check:
• Wheel bearings
“CHECKING THE FRONT WHEEL” on page
4-4and “CHECKING THE REAR WHEEL”
on page 4-8.
EAS1SL5112
CHECKING AND ADJUSTING THE STEER-
ING HEAD
1. Use a suitable stand to raise the front wheel
off the ground.
EWA13120
WARNING
Securely support the vehicle so that there is
no danger of it falling over.
2. Check:
• Steering head
Grasp the bottom of the front fork legs and
gently rock the front fork.
Blinding/looseness  Adjust the steering
head.
3. Remove:
• Handlebar
Refer to “HANDLEBAR” on page 4-31.
• Upper bracket
Refer to “STEERING HEAD” on page 4-49.
4. Adjust:
• Steering head
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Remove the washer “1”.
b. After loosening the ring nut “2” with a steer-
ing nut wrench “3”, tighten it to the specified
torque.
TIP
• Set the torque wrench at a right angle to the
steering nut wrench.
• Move the steering to the left and right a couple
of times to check that it moves smoothly. Spoke nipple wrench (6–7)
90890-01521
YM-01521
Spokes
2.5 Nm (0.25 m·kgf, 1.8 ft·lbf)
1
T R..
1

HANDLEBAR................................................................................................. 4-31
REMOVING THE HANDLEBAR............................................................... 4-33
CHECKING THE HANDLEBAR ............................................................... 4-33
INSTALLING THE HANDLEBAR ............................................................. 4-33
FRONT FORK................................................................................................. 4-37
REMOVING THE FRONT FORK LEGS ................................................... 4-39
DISASSEMBLING THE FRONT FORK LEGS ......................................... 4-39
CHECKING THE FRONT FORK LEGS ................................................... 4-40
ASSEMBLING THE FRONT FORK LEGS ............................................... 4-41
INSTALLING THE FRONT FORK LEGS ................................................. 4-47
STEERING HEAD........................................................................................... 4-49
REMOVING THE LOWER BRACKET...................................................... 4-50
CHECKING THE STEERING HEAD ........................................................ 4-50
INSTALLING THE STEERING HEAD ...................................................... 4-50
REAR SHOCK ABSORBER ASSEMBLY..................................................... 4-53
HANDLING THE REAR SHOCK ABSORBER ......................................... 4-56
DISPOSING OF A REAR SHOCK ABSORBER ...................................... 4-56
REMOVING THE REAR SHOCK ABSORBER ASSEMBLY.................... 4-56
REMOVING THE BEARING..................................................................... 4-56
CHECKING THE REAR SHOCK ABSORBER ASSEMBLY .................... 4-57
CHECKING THE CONNECTING ARM AND RELAY ARM ...................... 4-57
INSTALLING THE RELAY ARM............................................................... 4-57
INSTALLING THE REAR SHOCK ABSORBER ASSEMBLY .................. 4-58
SWINGARM.................................................................................................... 4-60
REMOVING THE SWINGARM................................................................. 4-61
REMOVING THE BEARING..................................................................... 4-61
CHECKING THE SWINGARM ................................................................. 4-61
INSTALLING THE SWINGARM ............................................................... 4-62
CHAIN DRIVE................................................................................................. 4-63
REMOVING THE DRIVE CHAIN.............................................................. 4-64
CHECKING THE DRIVE CHAIN .............................................................. 4-64
CHECKING THE DRIVE SPROCKET...................................................... 4-65
CHECKING THE REAR WHEEL SPROCKET ......................................... 4-65
INSTALLING THE DRIVE CHAIN ............................................................ 4-65

STEERING HEAD
4-49
EAS1SL5172
STEERING HEAD
Removing the lower bracket
Order Part name Q’ty Remarks
Use a suitable stand to raise the front wheel
off the ground.
Number plate Refer to “GENERAL CHASSIS” on page 4-1.
Handlebar Refer to “HANDLEBAR” on page 4-31.
1 Front fender 1
2 Steering stem nut 1
3 Front fork leg (s) 2 Refer to “FRONT FORK” on page 4-37.
4 Upper bracket 1
5 Steering ring nut 1
6 Lower bracket 1
7 Bearing race cover 1
8 Upper bearing 1
9 Bearing (lower side) 1
10 Bearing races 2
For installation, reverse the removal proce-
dure.
2
4
5
7
3
1
6
8
9
10
LS
1st
2ndT.R.
LS
LS
T.R.21 Nm (2.1 mlbf) kgf, 15 ft
T.R.9 Nm (0.9 mlbf) kgf, 6.5 ft
T.R.21 Nm (2.1 mlbf) kgf, 15 ft
T.R.10 Nm (1.0 mlbf) kgf, 7.2 ft
T.R.145 Nm (14.5 mlbf) kgf, 105 ft
38 Nm (3.8 m
lbf) kgf, 27 ft
7 Nm (0.7 m
lbf) kgf, 5.1 ft

STEERING HEAD
4-50
EAS1SL5173REMOVING THE LOWER BRACKET
1. Use a suitable stand to raise the front wheel
off the ground.
EWA13120
WARNING
Securely support the vehicle so that there is
no danger of it falling over.
2. Remove:
• Ring nut “1”
TIP
Remove the ring nut with the steering nut
wrench “2”.
EWA13730
WARNING
Securely support the lower bracket so that
there is no danger of it falling.
EAS1SL5174CHECKING THE STEERING HEAD
1. Wash with kerosene:
• Bearing
• Bearing races
2. Check:
• Bearing
• Bearing races
Damage/pitting  Replace.
3. Replace:
• Bearing
• Bearing races
▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼▼
a. Remove the bearing race from the steering
head pipe with a long rod “1” and a hammer.
b. Remove the bearing race from the lower
bracket with a chisel “2” and a hammer.
c. Install a new bearing race.
ECA14270
NOTICE
If the bearing race is not installed properly,
the steering head pipe could be damaged.
TIP
Always replace the bearing and the bearing
race as a set.
▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲▲
4. Check:
• Upper bracket
• Lower bracket
(along with the steering stem)
Bends/cracks/damage  Replace.
EAS1SL5175INSTALLING THE STEERING HEAD
1. Install:
• Lower bearing “1”
TIP
Apply the lithium soap base grease on the dust
seal lip and bearing inner circumference. Steering nut wrench
90890-01403
Exhaust flange nut wrench
YU-A9472