2009 YAMAHA YFZ450R engine

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EBU29380
Indicator light and warning lights
EBU17860
Neutral indicator light “”
This indicator light comes on when the transmis-
sion is in the neutral position.
EBU26700
Coolant temperature warning light “”
This warning light comes on when the engine over-
heats. When this occurs during operation, stop theengine as soon as it is safe to do so and allow it to
cool down for about 10 minutes.
The electrical circuit of the warning light can be
checked by turning the key to “ON”. If the warning
light does not come on, and then go off, have a
Yamaha dealer check the electrical circuit.
NOTICE
ECB00010

The engine may overheat if the ATV is over-
loaded. In this case, reduce the load to spec-
ification.

Start the engine after making sure that the
warning light is out. Continuous use while
the warning light is on may cause damage to
the engine.
EBU29390
Fuel level warning light “”
This warning light comes on when the fuel level
drops below approximately 3.4 L (0.90 US gal,
0.75 Imp.gal). When this occurs, refuel as soon as
possible.
The electrical circuit of the warning light can be
checked by setting the engine stop switch to “ ”
and turning the key to “ON”. If the warning light
does not come on, and then go off, have a Yamaha
dealer check the electrical circuit.
1. Fuel level warning light “ ”
2. Engine trouble warning light “ ”
3. Coolant temperature warning light “ ”
4. Neutral indicator light “N”
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EBU26720
Engine trouble warning light “”
This warning light comes on or flashes when an
electrical circuit monitoring the engine is defective.
When this occurs, have a Yamaha dealer check
the self-diagnosis system.
The electrical circuit of the warning light can be
checked by turning the key to “ON”. If the warning
light does not come on, then go off, have a
Yamaha dealer check the electrical circuit.
EBU18061
Handlebar switches
EBU18080
Engine stop switch “/”
Set this switch to “ ” before starting the engine.
The engine stop switch controls the ignition and
stops the engine when it is running. Use this switch
to stop the engine in an emergency situation. The
engine will not start or run when this switch is set
to “ ”.
EBU18100
Start switch “”
Push this switch to crank the engine with the start-
er.NOTICE
ECB00050
See the starting instructions on page 6-1 prior
to starting the engine.
EBU18151
Light switch “/ /OFF”
Set this switch to “ ” to turn on the low beams
and the taillight. Set the switch to “ ” to turn on
the high beams and the taillight. Set the switch to
“OFF” to turn off all the lights.NOTICE

ECB00040
Do not use the headlights with the engine
1. Light switch “ / /OFF”
2. Engine stop switch “ / ”
3. Start switch “ ”
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turned off for an extended period of time, oth-
erwise the battery may discharge to the point
that the starter motor will not operate properly.
If this should happen, remove the battery and
recharge it.
EBU18280
Throttle lever
Once the engine is running, movement of the throt-
tle lever will increase the engine speed.
Regulate the speed of the ATV by varying the
throttle position. Because the throttle is spring-
loaded, the ATV will decelerate, and the engine will
return to an idle any time the hand is removed from
the throttle lever.Before starting the engine, check the throttle to be
sure it is operating smoothly. Make sure it returns
to the idle position as soon as the lever is released.
WARNING

EWB00250
Malfunction of the throttle could make it diffi-
cult to speed up or slow down when you need
to. This could cause an accident. Check the op-
eration of the throttle lever before you start the
engine. If the throttle does not work smoothly,
check for the cause. Correct the problem be-
fore riding the ATV or consult a Yamaha dealer.
1. Throttle lever

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EBU18321
Speed limiter
Your ATV was delivered with an adjustable speed
limiter. The speed limiter keeps the throttle from
fully opening, even when the throttle lever is
pushed to the maximum.
1. Loosen the locknut.
2. To increase the maximum engine power avail-
able and the maximum speed of the ATV, turn
the adjusting screw in direction (a). To de-
crease the maximum engine power available
and the maximum speed of the ATV, turn the
adjusting screw in direction (b).
3. Tighten the locknut.
WARNING

EWB00240
Improper adjustment of the speed limiter and
throttle could cause throttle cable damage or
improper throttle operation. You could lose
control, have an accident or be injured. Do not
turn the adjusting screw out more than 12 mm
(0.47 in) or the throttle cable could be dam-
aged. Always make sure the throttle lever free
play is adjusted to 2.0–4.0 mm (0.08–0.16 in).
(See page 8-28.)
1. Locknut
2. Adjusting screw
3. No more than 12 mm (0.47 in)
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(a)
(b)

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EBU18432
Brake pedal
The brake pedal is located on the right side of the
ATV. To apply the rear brake, push down on the
brake pedal.
EBU18520
Parking brake lever
Use the parking brake before starting the engine or
parking the ATV, especially on a slope. To apply
the parking brake, move the parking brake lever in
direction (a). To release the parking brake, move
the parking brake lever in direction (b).
1. Brake pedal
1

1. Parking brake lever (locked position)
1. Parking brake lever (unlocked position)

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WARNING

EWB00220

Always set the parking brake before starting
the engine. The ATV could start moving un-
expectedly if the parking brake is not ap-
plied. This could cause loss of control or a
collision.

Always be sure you have released the park-
ing brake before you begin to ride. The brake
could overheat if you ride the ATV without re-
leasing the parking brake. You could lose
braking performance which could cause an
accident. You could also wear out the brakes
prematurely.
EBU18530
Shift pedal
This ATV is equipped with a constant-mesh 5-
speed transmission. The shift pedal is located on
the left side of the engine and is used in combina-
tion with the clutch when shifting.
EBU18720
Fuel tank cap
Remove the fuel tank cap by turning it counter-
clockwise.
1. Shift pedal
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TIP

If knocking or pinging occurs, use a different brand
of gasoline or higher octane grade.
NOTICE

ECB00070
Use 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.
WARNING

EWB00310

Do not overfill the fuel tank. Fuel expands
when it heats up. If the fuel tank is overfilled,
fuel could spill out due to heat from the en-
gine or the sun.

Be careful not to spill fuel, especially on the
engine or exhaust pipe which can cause a
fire and severe injury. Wipe up any spilled
fuel immediately.

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

Be sure the fuel tank cap is closed securely.
EBU18890
Seat
To remove the seat
Insert your hand between the rear of the seat and
the rear fender, pull the seat lock lever upward and
pull up the seat at the rear.
To install the seat
Insert the projections on the front of the seat into
the seat holders and push down on the seat at the
rear.

1. Seat lock lever
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EBU19200
PRE-OPERATION CHECKS
EBU19223
Pre-operation check list
Before operating this ATV, be sure to check the items listed in the following table.
WARNING

EWB00480
Always inspect your ATV each time you use it to make sure it is in safe operating condition.
Always follow the inspection and maintenance procedures and schedules described in the Owner’s
Manual. Failure to inspect increases the possibility of an accident or equipment damage.
TIP

The maintenance of some items in the table has to be performed by a Yamaha dealer. Refer to the periodic
maintenance charts on page 8-3 to determine which service should be performed by a Yamaha dealer.
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.4-9, 5-4
Engine oil

Check oil level in engine, and add recommended oil to specified
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, 8-19