fuel YAMAHA YFZ450 2012 Owners Manual

EBU17420
TABLE OF CONTENTS
LOCATION OF THE WARNING AND
SPECIFICATION LABELS ............................ 1-1
SAFETY INFORMATION .............................. 2-1
DESCRIPTION .............................................. 3-1Left view ...................................................... 3-1
Right view.................................................... 3-1
Controls and instruments ............................ 3-2
INSTRUMENT AND CONTROL
FUNCTIONS .................................................. 4-1 Main switch ................................................ 4-1
Indicator light and warning light .................. 4-2
Handlebar switches .................................... 4-3
Throttle lever .............................................. 4-3
Speed limiter .............................................. 4-4
Clutch lever ................................................ 4-5
Brake lever ................................................. 4-5
Brake pedal ................................................ 4-6
Parking brake lever .................................... 4-6
Shift pedal .................................................. 4-7
Fuel tank cap .............................................. 4-8
Fuel ............................................................ 4-8 Fuel cock ..................................................4-10
Starter (choke) ..........................................4-11
Seat ..........................................................4-12
Adjusting the front shock absorber
assemblies ..............................................4-13
Adjusting the rear shock absorber assembly .................................................4-14
PRE-OPERATION CHECKS ..........................5-1 Fuel .............................................................5-4
Engine oil ....................................................5-4
Coolant .......................................................5-4
Front and rear brakes .................................5-4
Throttle lever ...............................................5-5
Drive chain ..................................................5-5
Tires ............................................................5-5
Chassis fasteners .......................................5-7
Instruments, lights and switches .................5-7
OPERATION...................................................6-1 Starting a cold engine .................................6-1
Starting a warm engine ...............................6-3
Shifting ........................................................6-3
Engine break-in ...........................................6-5U1PD60E0.book Page 1 Monday, June 13, 2011 2:57 PM

1-5
1
**.* kPa
*.** kgf/cm²*.* psi **.* kPa
*.** kgf/cm²
*.* psi
NEVER use with drugs or alcohol.
NEVER store fuel or flammable liquids.
This unit contains high-pressure nitrogen
gas.
Mishandling can cause an explosion. Do not
incinerate, puncture or open.
Use unleaded gasoline only.
Measure the tire pressure when the tires are
cold. Adjust the tire pressure.
Improper tire pressure can cause loss of
control.
Loss of control can result in severe injury or
death.
Turning the ATV in 4WD-LOCK
(“DIFF.LOCK”) takes more effort.
Operate at a slow speed and allow extra
time and distance for maneuvers to avoid
loss of control.
This pictogram shows the loading limits
and/or maximum load capacity for this ATV.
Follow all load limits and other loading
guidelines in this manual.
Load may include the driver, passenger,
human protective gear, accessories, goods,
luggage, and all other load related items.
Make sure you do not exceed the load limits.
Overloading can cause loss of control.
Loss of control can result in severe injury or
death.
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2-4
2
closed or poorly ventilated areas. If you experi-
ence any symptoms of carbon monoxide
poisoning, leave the area immediately, get
fresh air, and SEEK MEDICAL TREATMENT.

Do not run engine indoors. Even if you try to
ventilate engine exhaust with fans or open
windows and doors, carbon monoxide can
rapidly reach dangerous levels.
Do not run engine in poorly ventilated or par-
tially enclosed areas such as barns, garages,
or carports.
Do not run engine outdoors where engine
exhaust can be drawn into a building
through openings such as windows and
doors.
WARNING
EWB02591When transporting the ATV in another vehicle,
be sure it is kept upright and that the fuel cock
is in the
“OFF ” position. Otherwise, fuel may
leak out of the carburetor or fuel tank.U1PD60E0.book Page 4 Monday, June 13, 2011 2:57 PM

3-1
3
EBU17680
DESCRIPTION
EBU17690Left view
EBU17700Right view
1. Headlights
2. Fuel cock
3. Starter (choke)
4. Fuse
5. Tail/brake light
6. Coolant reservoir
7. Shift pedal
8. Engine oil tank
123 45
6
7
8
1. Spark arrester
2. Seat
3. Fuel tank cap
4. Radiator cap
5. Oil filter element
6. Brake pedal1
23
4
5
6
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4-8
4
EBU18720Fuel tank cap Remove the fuel tank cap by turning it counter-
clockwise.
EBU18814Fuel Make sure there is sufficient gasoline in the tank.
WARNING
EWB02521Gasoline and gasoline vapors are extremely
flammable. To avoid fires and explosions and
to reduce the risk of injury when refueling, fol-
low these instructions.1. Before refueling, turn off the engine and besure that no one is sitting on the vehicle. Nev-
er refuel while smoking, or while in the vicinity
1. Shift pedal
1
1. Fuel tank cap
1
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4-9
4of sparks, open flames, or other sources of ig-
nition such as the pilot lights of water heaters
and clothes dryers.
2. Do not overfill the fuel tank. When refueling, be sure to insert the pump nozzle into the fuel
tank filler hole. Stop filling when the fuel reach-
es the bottom of the filler tube. Because fuel
expands when it heats up, heat from the en-
gine or the sun can cause fuel to spill out of
the fuel tank.
3. Wipe up any spilled fuel immediately.NOTICE: Immediately wipe off spilled fuel
with a clean, dry, soft cloth, since fuel may
deteriorate painted surfaces or plastic
parts.
[ECB00981]
4. Turn the fuel tank cap fully clockwise to make sure it is securely closed.
WARNING
EWB02531Gasoline is poisonous and can cause injury or
death. Handle gasoline with care. Never siphon
gasoline by mouth. If you should swallow
some gasoline or inhale a lot of gasoline vapor,
or get some gasoline in your eyes, see your
1. Maximum fuel level
2. Fuel tank filler tube
Recommended fuel:PREMIUM UNLEADED GASOLINE ONLY
For Europe: PREMIUM UNLEADED GASO-
LINE ONLY with a research octane number
of 97 or higher
Fuel tank capacity: 10.0 L (2.64 US gal, 2.20 Imp.gal)
Fuel reserve amount: 1.9 L (0.50 US gal, 0.42 Imp.gal)
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4-10
4
doctor immediately. If gasoline spills on your
skin, wash with soap and water. If gasoline
spills on your clothing, change your clothes.
NOTICEECB00070Use only unleaded gasoline. The use of leaded
gasoline will cause severe damage to internal
engine parts, such as the valves and piston
rings, as well as to the exhaust system.Your Yamaha engine has been designed to use
premium unleaded gasoline with a research oc-
tane number of 97 or higher. If knocking (or ping-
ing) occurs, use a gasoline of a different brand.
Use of unleaded fuel will extend spark plug life and
reduce maintenance costs.EBU18820Fuel cock The fuel cock supplies fuel from the tank to the car-
buretor while also filtering it.
The fuel cock lever positions are explained as fol-
lows and shown in the illustrations. OFF
With the fuel cock lever in this position, fuel will not
flow. Always turn the fuel cock lever to this position
when the engine is not running.
1. Arrow mark positioned over
“OFF”
1
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4-11
4ON
With the fuel cock lever in this position, fuel flows
to the carburetor. Turn the fuel cock lever to this
position when starting the engine and riding. RES
This indicates reserve. With the fuel cock lever in
this position, the fuel reserve is made available.
Turn the fuel cock lever to this position if you run
out of fuel while riding. When this occurs, refuel as
soon as possible and be sure to turn the fuel cock
lever back to
“ON ”!
EBU18840Starter (choke) Starting a cold engine requires a richer air-fuel mix-
ture, which is supplied by the starter (choke).
Move the starter (choke) in direction (a) to turn on
the starter (choke).
1. Arrow mark positioned over “ON ”
1
1. Arrow mark positioned over “RES ”
1
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5-1
5
EBU19201
PRE-OPERATION CHECKS
EBU19224Inspect your vehicle each time you use it to make sure the vehicle is in safe operating condition. Always
follow the inspection and maintenance procedures and schedules described in the Owner’s Manual.
WARNING
EWB00481Failure to inspect or maintain the vehicle properly increases the possibility of an accident or equip-
ment damage. Do not operate the vehicle if you find any problem. If a problem cannot be corrected
by the procedures provided in this manual, have the vehicle inspected by a Yamaha dealer.Before using this vehicle, check the following points:
ITEM ROUTINE PAGE
Fuel 
Check fuel level in fuel tank, and add recommended fuel if neces-
sary.
 Check fuel line for leakage. Correct if necessary. 4-8, 5-4
Engine oil 
Check oil level in engine oil tank, and add recommended oil to spec-
ified level if necessary.
 Check ATV for oil leakage. Correct if necessary. 5-4, 8-14
Coolant 
Check coolant level in reservoir, and add recommended coolant to
specified level if necessary.
 Check cooling system for leakage. Correct if necessary. 5-4, 8-20
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EBU19541Fuel Make sure that there is sufficient fuel in the tank.
(See page 4-8.)EBU19560Engine oil Make sure that the engine oil is at the specified lev-
el. Add oil as necessary. (See page 8-14.)EBU19631Coolant Make sure that the coolant is at the specified level.
Add coolant as necessary. (See page 8-20.)TIPThe coolant level must be checked on a cold en-
gine since the level varies with engine tempera-
ture.EBU19712Front and rear brakes Brake lever and brake pedal
Check that there is no free play in the brake le-
ver. If there is free play, have a Yamaha dealer
check the brake system.

Check for correct brake pedal height. (See page
8-36.) If the pedal height is incorrect, have a
Yamaha dealer adjust it.
Check the operation of the lever and pedal. They
should move smoothly and there should be a
firm feeling when the brakes are applied. If not,
have a Yamaha dealer check the brake system.
Brake fluid level
Check the brake fluid level. Add fluid if necessary.
(See page 8-33.)
Brake fluid leakage
Check to see if any brake fluid is leaking out of the
pipe joints or brake fluid reservoirs. Apply the
brakes firmly for one minute. If there is any leak-
age, have a Yamaha dealer check the brake sys-
tem.
Brake operation
Test the brakes at slow speed after starting out to
make sure they are working properly. If the brakes
do not provide proper braking performance, check
the brake pads for wear. (See page 8-32.) Specified brake fluid:
DOT 4
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