2014 YAMAHA YZ450F Front

1
GENERAL INFORMATION
LOCATION OF IMPORTANT LABELS............................................................ 1-1
DESCRIPTION .................................................................................................. 1-4
IDENTIFICATION ............................................................................................. 1-5
VEHICLE IDENTIFICATION NUMBER ...................................................... 1-5
ENGINE SERIAL NUMBER ....................................................................... 1-5
MODEL LABEL........................................................................................... 1-5
FEATURES ....................................................................................................... 1-6
OUTLINE OF THE FI SYST EM .................................................................. 1-6
FI SYSTEM....................................... .......................................................... 1-7
INCLUDED PARTS .......................................................................................... 1-8
SIDESTAND ............................................................................................... 1-8
SPARK PLUG WRENCH ........................................................................... 1-8
NIPPLE WRENCH...................................................................................... 1-8
HANDLEBAR PROTECTOR .. .................................................................... 1-8
FUEL HOSE JOINT COVER ...................................................................... 1-8
COUPLER FOR CONNECTING OPTIONAL PART................................... 1-8
IMPORTANT INFORMATION ........................................................................ 1-10
PREPARATION FOR REMOVAL A ND DISASSEMBLY.......................... 1-10
REPLACEMENT PARTS.......................................................................... 1-10
GASKETS, OIL SEALS AND O-RINGS ................................................... 1-11
LOCK WASHERS/PLATES AND COTTER PINS .................................... 1-11
BEARINGS AND OIL SEALS ................................................................... 1-11
CIRCLIPS ................................................................................................. 1-11
BASIC SERVICE INFORMATION .................................................................. 1-12
ELECTRICAL SYSTEM.......... .................................................................. 1-12
SPECIAL TOOLS ........................................................................................... 1-15
CONTROL FUNCTIONS ................................................................................ 1-20
ENGINE STOP SWITCH .......................................................................... 1-20
CLUTCH LEVER ................................................................................... ... 1-20
SHIFT PEDAL .......................................................................................... 1-20
KICKSTARTER LEVER.......... .................................................................. 1-20
THROTTLE GRIP ..................................................................................... 1-20
FRONT BRAKE LEVER ........................................................................... 1-20
REAR BRAKE PEDAL.............................................................................. 1-21
STARTER KNOB/IDLE SCREW .............................................................. 1-21
FUEL TANK CAP ..................................................................................... 1-21

DESCRIPTION
1-4
EAS1SL1009
DESCRIPTION
TIP
Designs and specifications of the vehicle are subject to change without notice. Therefore, please
note that the descriptions in this manual may be different from those for the vehicle you have pur
-
chased.
1. Clutch lever10. Coolant drain bolt
2. Front brake lever11. Rear brake pedal
3. Throttle grip12. Air filter
4. Radiator cap13. Drive chain
5. Fuel tank cap14. Shift pedal
6. Engine stop switch15. Oil level check window
7. Fuel tank16. Starter knob/idle screw
8. Kickstarter lever17. Front fork
9. Radiator
2 1
6
78 954 3
11 10 17 16 15 14 1312

SPECIAL TOOLS
1-16
Radiator cap tester
90890-01325
Mityvac cooling system tester
kit
YU-24460-A
This tool is used to check the
radiator and the radiator cap.
Radiator cap tester adapter
90890-01352
Pressure tester adapter
YU-33984
This tool is used to check the
radiator and the radiator cap.
Steering nut wrench
90890-01403
Exhaust flange nut wrench
YU-A9472
This tool is used to remove or
tighten the steering nut.
Cap bolt wrench
90890-01500
YM-01500
This tool is used to remove or
tighten the base valve.
Cap bolt ring wrench
90890-01501
YM-01501
This tool is used to loosen or
tighten the damper assem
-
bly.
Fork seal driver
90890-01502
YM-A0948
This tool is used to install the
oil seal of the front fork.
Spoke nipple wrench (6–7)
90890-01521
YM-01521
This tool is used to tighten the
spoke.
Tool name/Part number How to use Illustration

CONTROL FUNCTIONS
1-20
EAS1SL1032
CONTROL FUNCTIONS
EAS1SL1033ENGINE STOP SWITCH
The engine stop switch “1” is located on the left
handlebar. Continue pushing the engine stop
switch till the engine comes to a stop.
EAS1SL1034CLUTCH LEVER
The clutch lever “1” is located on the left han-
dlebar. The clutch lever disengages or engag-
es the clutch.
Pull the clutch lever toward the handlebar to
disengage the clutch, and release the lever to
engage the clutch.
EAS1SL1035SHIFT PEDAL
The shift pedal “1” has adopted a method of 1
down & 4 ups (press-down & kick-ups).
Press it down for N (neutral) to 1st, and kick it
up for 2nd to 5th.
EAS1SL1036
KICKSTARTER LEVER
The kickstarter lever “1” is in the right of the
chassis.
To start the engine, pull out and push down the
kickstarter lever with your foot.
EAS1SL1037THROTTLE GRIP
The throttle grip “1” is located on the right han-
dlebar. The throttle grip accelerates or deceler-
ates the engine. For acceleration, turn the grip
toward you; for deceleration, turn it away from
you.
EAS1SL1038FRONT BRAKE LEVER
The front brake lever “1” is located on the right
handlebar. Pull it toward the handlebar to acti
-
vate the front brake.
EAS1SL1039
1
1

MAINTENANCE AFTER BREAK-IN
1-24
MAINTENANCE AFTER BREAK-IN
After a break-in, perform careful maintenance
to get ready for the next practice or race.
Refer to “PRE-OPERATION INSPECTION
AND MAINTENANCE” on page 3-7.
EAS1SL1047MAJOR MAINTENANCE
1. For the engine
• Leaks around the engine
Check for pressure leaks from the cylinder
head or the cylinder, oil leaks from the
crankcase or the case cover, leaks from the
coolant system, and other leaks.
• Check that the valve, the cylinder head, the
cylinder, the piston, and the piston ring fit
one another, and that contact between the
valve and the cylinder head, and that be
-
tween the cylinder and the piston are cor-
rect.
• Engine oil change
Drain the oil, and check for dirt and foreign
materials such as metal chips. (If any foreign
material is mixed, disassemble and check
the crankcase.)
Pour the specified amount of the recom-
mended oil.
• AC magneto
Check for looseness in mounted areas of
the rotor and the stator.
Check that the connector is not being dis-
connected.
• Silencer
Check the main body and stay for cracks.
Check for leaks.
• Mounting bolts and nuts
Check for looseness in mounted areas of
parts, as well as engine mounting bolts and
engine brackets.
2. For the chassis
• Check welds and mounted areas of the
frame, the swingarm, the link, the bracket,
and so on, for looseness and cracks.
• Wheel (s)
Check the wheel for runout. Check the
spoke for looseness.
• Brake(s)
Check the brake disc mounting bolt for
looseness.
Check that the reservoir contains the speci-
fied amount of brake fluid. Check for leaks.
• Cable
Grease and adjust cables.
•Drive chain
Lubricate the drive chain and adjust its ten-
sion.
• Fuel tank
Clean the inside of the fuel tank. Check for
leaks.
• Suspension
Check for oil leaks in the front fork or the rear
shock absorber. Check that the mounted
conditions are good.
• Sprocket
Check for looseness in the sprocket mount-
ed on the rear wheel.
• Mounting bolts and nuts
Check mounted areas for looseness.JCA1SL1001
NOTICE
After a break-in or before each race, always
check the points shown in “TORQUE-
CHECK POINTS” for tightening torques and
retighten them. (Refer to
“TORQUE-CHECK
POINTS”.)
• Greasing and oiling
Always grease or oil the specified points.

TORQUE-CHECK POINTS
1-25
EAS1SL1048
TORQUE-CHECK POINTS
Frame constructionFrame to rear frame
Frame to engine protector
Combined seat and fuel tankFuel tank to frame
Engine mountingFrame to engine
Engine bracket to engine
Engine bracket to frame
SeatSeat to frame
SteeringSteering stem to handlebarSteering stem to frame
Steering stem to upper bracket
Upper bracket to handlebar
SuspensionFrontSteering stem to front forkFront fork to upper bracket
Front fork to lower bracket
RearLinkAssembly of links
Link to frame
Link to rear shock absorber
Link to swingarm
Mounting of rear shock absorberRear shock absorber and frame
Mounting of swingarmTightening of pivot shaft
Wheel (s)Mounting of wheelFrontTightening of wheel axle
Tightening of axle holder
Tightening of spoke nipple
RearTightening of wheel axle
Wheel to rear wheel sprocket
Tightening of spoke nipple
Brake(s)FrontBrake 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
RearBrake 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 systemFuel pump to fuel tank

TORQUE-CHECK POINTS
1-26
TIP
Concerning the tightening torque, refer to “TIGHTENING TORQUES” on page 2-13.
Plastic coverTightening of number plate
Tightening of front fender
Tightening of fork leg protector
Tightening of air scoop
Left cover to rear frame
Tightening of side cover
Tightening of rear fender
Tightening of mud flap
Tightening of rear brake disc cov-
er
Tightening of rear brake caliper
cover

CHASSIS SPECIFICATIONS
2-8
EAS1SL1054
CHASSIS SPECIFICATIONS
Chassis
Frame type Semi double cradle
Caster angle 27.08 ° (USA) (CAN)
27.50 ° (EUR)
27.67 ° (JPN)
27.58 ° (AUS) (NZL) (ZAF)
Trail 120 mm (4.7 in) (USA) (CAN)
122 mm (4.8 in) (EUR)
124 mm (4.9 in) (JPN) (AUS) (NZL) (ZAF)
Front wheel
Wheel type Spoke wheel
Rim size 21  1.60
Rim material Aluminum
Wheel travel 310.0 mm (12.20 in)
Radial wheel runout limit 2.0 mm (0.08 in)
Lateral wheel runout limit 2.0 mm (0.08 in)
Wheel axle bending limit 0.50 mm (0.02 in)
Rear wheel
Wheel type Spoke wheel
Rim size 19  2.15
Rim material Aluminum
Wheel travel 315.0 mm (12.40 in)
Radial wheel runout limit 2.0 mm (0.08 in)
Lateral wheel runout limit 2.0 mm (0.08 in)
Wheel axle bending limit 0.50 mm (0.02 in)
Front tire
Type With tube
Size 80/100-21 51M
Manufacturer/model DUNLOP/MX51FA (USA) (CAN)
PIRELLI/MID SOFT 32 (EUR)
BRIDGESTONE/M601 (JPN)
DUNLOP/MX51FA (AUS) (NZL) (ZAF)
Rear tire
Type With tube
Size 120/80-19 63M (USA) (CAN)
110/90-19 62M (EUR) (JPN)
120/80-19 63M (AUS) (NZL) (ZAF)
Manufacturer/model DUNLOP/MX51 (USA) (CAN)
PIRELLI/MID SOFT 32 (EUR)
BRIDGESTONE/M602 (JPN)
DUNLOP/MX51 (AUS) (NZL) (ZAF)
Tire air pressure (measured on cold tires)
Front 100 kPa (1.00 kgf/cm2, 15 psi)
Rear 100 kPa (1.00 kgf/cm2, 15 psi)
Front brake
Type Single disc brake
Operation Right hand operation
Front disc brake
Disc outside diameter  thickness 250.0  3.0 mm (9.84  0.12 in)