2012 YAMAHA YFZ450 engine

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EBU17805Indicator light and warning light EBU17860Neutral indicator light“”
This indicator light comes on when the transmis-
sion is in the neutral position.EBU17930Coolant temperature warning light “”
This warning light comes on when the engine over-
heats. When this occurs during operation, stop the
engine 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 according to the following procedure.
1. Set the engine stop switch to “” and turn
the key to “ON ”.
2. Shift the transmission into the neutral position or pull the clutch lever.
3. Push the start switch. If the warning light does not come on while the start switch is pushed,
have a Yamaha dealer check the electrical cir-
cuit.
NOTICEECB00010
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.
1. Neutral indicator light “N”
2. Coolant temperature warning light “”
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EBU18061Handlebar switches EBU18080Engine 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 “” .
EBU18101Start switch “”
Push this switch to crank the engine with the start-
er. See the starting instructions on page 6-1 prior
to starting the engine.EBU18154Light 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.NOTICEECB00043Do not use the headlights with the engine
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. (See page 8-48.)EBU18282Throttle lever Once the engine is running, pushing the throttle le-
ver will increase the engine speed.
1. Light switch “/ /OFF”
2. Engine stop switch “/”
3. Start switch “”
1
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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 throttle lever is re-
leased.
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.
EBU18323Speed limiter Your ATV is equipped 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). 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 8-31.) WARNING! Improper ad-
justment of the speed limiter and throttle
could cause throttle cable damage or im-
proper throttle operation. You could lose
control, resulting in an accident.
[EWB00241]
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EBU18432Brake pedal The brake pedal is located on the right side of the
ATV. To apply the rear brake, push down on the
brake pedal.
EBU18520Parking 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 lever
1
1. Brake pedal
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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.EBU18530Shift 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.
1. Parking brake lever (locked position)
1. Parking brake lever (unlocked position)U1PD60E0.book Page 7 Monday, June 13, 2011 2:57 PM

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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
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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”
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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 ”
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