2005 YAMAHA YFZ450 engine

EBU00150
1-CONTENTS
LOCATION OF THE WARNING
AND SPECIFICATION LABELS .............. 1-1
SAFETY INFORMATION ......................... 2-1
DESCRIPTION AND MACHINE
IDENTIFICATION .................................... 3-1
Identification number records ............... 3-3
Key identification number ..................... 3-5
Vehicle identification number ............... 3-5
Model label ........................................... 3-7
CONTROL FUNCTIONS ......................... 4-1
Main switch........................................... 4-1
Indicator and warning lights.................. 4-3
Handlebar switches .............................. 4-7
Throttle lever ...................................... 4-11
Speed limiter ...................................... 4-13
Clutch lever ........................................ 4-15
Brake lever ......................................... 4-17
Brake pedal ........................................ 4-17
Parking brake lever ............................ 4-19
Shift pedal .......................................... 4-21
Fuel tank cap ...................................... 4-21
1234
Fuel cock............................................ 4-23
Starter (choke) .................................. 4-25
Seat.................................................... 4-27
Front shock absorber adjustment ...... 4-29
Rear shock absorber adjustment ....... 4-39
PRE-OPERATION CHECKS ................... 5-1
Front and rear brakes .......................... 5-5
Fuel ...................................................... 5-9
Engine oil ........................................... 5-13
Coolant............................................... 5-15
Chain.................................................. 5-17
Throttle lever ...................................... 5-17
Fittings and fasteners......................... 5-19
Lights ................................................. 5-19
Switches............................................. 5-19
Tires ................................................... 5-21
How to measure tire pressure ............ 5-25
Tire wear limit..................................... 5-27
5
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OPERATION ............................................6-1
Starting a cold engine ...........................6-3
Starting a warm engine .........................6-9
Warming up...........................................6-9
Shifting ................................................6-11
To start out and accelerate .................6-13
To decelerate ......................................6-17
Engine break-in ...................................6-19
Parking ................................................6-23
Parking on a slope ..............................6-25
Accessories and loading .....................6-29
RIDING YOUR ATV..................................7-1
Getting to know your ATV .....................7-3
Ride with care and good judgement .....7-5
Be careful where you ride ...................7-27
Turning your ATV ................................7-41
Climbing uphill.....................................7-47
Riding downhill ....................................7-57
Crossing a slope .................................7-61
Crossing through shallow water ..........7-65
Riding over rough terrain ....................7-69
Sliding and skidding ............................7-71
What to do if ........................................7-75
What to do...........................................7-75
67
PERIODIC MAINTENANCE AND
ADJUSTMENT ......................................... 8-1
Owner’s manual and tool kit ................. 8-3
Periodic maintenance/lubrication.......... 8-7
Panel removal and installation............ 8-17
Engine oil and oil filter element........... 8-23
Cooling system ................................... 8-41
Changing the coolant.......................... 8-45
Spark plug inspection ......................... 8-53
Air filter element cleaning ................... 8-65
Carburetor adjustment ........................ 8-73
Idle speed adjustment ........................ 8-75
Valve clearance adjustment ............... 8-75
Throttle lever adjustment .................... 8-77
Front brake pad inspection ................. 8-79
Rear brake pad inspection.................. 8-81
Brake fluid level inspection ................. 8-83
Brake fluid replacement ...................... 8-87
Front brake lever free play.................. 8-89
Brake pedal height adjustment ........... 8-91
Parking brake adjustment ................... 8-93
Adjusting the rear brake light switch ... 8-97
Clutch lever free play adjustment ....... 8-99
Drive chain slack check .................... 8-101
Drive chain slack adjustment ............ 8-103
Lubricating the drive chain................ 8-107
Cable inspection and lubrication....... 8-111
8
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2-1
SAFETY INFORMATION
EBU12713
AN ATV IS NOT A TOY AND CAN BE HAZARD-OUS TO OPERATE.
An ATV handles differently
from other vehicles including motorcycles and
cars. A collision or rollover can occur quickly, even
during routine maneuvers such as turning and
riding on hills or over obstacles, if you fail to take
proper precautions. SEVERE INJURY OR DEATH
can result if you do not follow these instructions:


Read this manual and all labels carefully and
follow the operating procedures described.


Never operate an ATV without proper instruc-
tion.


Always follow the age recommendation:
– A child under 16 years old should never oper-
ate an ATV with engine size greater than 90cc.
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2-17
WARNING
_

Always turn off the engine when refueling.


Do not refuel immediately after the engine
has been running and is still very hot.


Do not spill gasoline on the engine or ex-
haust pipe/muffler when refueling. Never
refuel while smoking or in the vicinity of
sparks, open flames, or other sources of
ignition such as the pilot lights of water
heaters and clothes dryers. Gasoline can
catch fire. You could be burned.


When transporting the machine in another
vehicle, be sure it is kept upright and that
the fuel cock is in the “OFF” position. Oth-
erwise, fuel may leak out of the carburetor
or fuel tank.


Gasoline is poisonous. If you should swal-
low some gasoline or inhale a lot of gaso-
line vapor, or get some gasoline in your
eyes, see your doctor immediately. If gaso-
line spills on your skin, wash with soap
and water. If gasoline spills on your cloth-
ing, change your clothes.
_
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2-19
WARNING
_ Always operate your ATV in an area with ade-
quate ventilation. Never start or run the engine
in a closed area. Exhaust fumes are poisonous
and may cause loss of consciousness and
death within a short time. _
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3-1
EBU00320
1-DESCRIPTION AND MACHINE
IDENTIFICATION1. Seat
2. Fuel tank cap
3. Radiator cap
4. Oil filter element
5. Brake pedal
6. Headlights
7. Fuel cock
8. Starter (choke)
9. Throttle stop screw
10. Fuse11. Tail/brake light
12. Coolant reservoir
13. Shift pedal
14. Engine oil tank
15. Clutch lever
16. Handlebar switches
17. Parking brake lever
18. Main switch
19. Throttle lever
20. Brake leverNOTE:_ The machine you have purchased may differ
slightly from those shown in the figures of this
manual. _
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4-1
EBU00400
1-CONTROL FUNCTIONS
EBU00420
Main switch
Functions of the respective switch positions are as
follows:
ON:
The engine can be started only at this position.
OFF:
All electrical circuits are switched off. The key can
be removed in this position.
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4-3 1. Neutral indicator light “N”
2. Coolant temperature warning light “”
1. Témoin de point mort “N”
2. Témoin d’avertissement de la température du liquide de
refroidissement “”
1. Luz de control de punto muerto “N”
2. Luz de aviso de la temperatura del refrigerante “”
EBU08020
Indicator and warning lights
EBU06030
Neutral indicator light “N”
This indicator light comes on when the transmis-
sion is in neutral.
EBU13850
Coolant temperature warning light “”
When the coolant temperature reaches a specified
level, this light comes on to warn that the coolant
temperature is too hot. If the light comes on during
operation, stop the engine as soon as it is safe to
do so and allow the engine to cool down for about
10 minutes.
The electrical circuit of the warning light can be
checked according to the following procedures.
1. Set the engine stop switch to “RUN” and turn
the key to “ON”.
2. Shift the transmission into the neutral position
or pull the clutch lever.
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