2018 YAMAHA YFZ450R engine

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EBU17739
INSTRUMENT AND CONTROL FUNCTIONS
EBU29913Main switch“” (on)
All electrical systems are supplied with power. The
engine can be started. The key cannot be re-
moved.
“ ” (off)
All electrical systems are off. The key can be re-
moved.
EBU29383Indicator light and warning lightsEBU17861Neutral indicator light “ ”
This indicator light comes on when the transmis-
sion is in the neutral position.
1. Main switch
OFF
ON
1
1. Fuel level warning light “ ”
2. Engine trouble warning light “ ”
3. Coolant temperature warning light “ ”
4. Neutral indicator light “N”
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EBU29923Coolant temperature warning light “ ”
This warning light comes on when the engine
overheats. When this occurs, stop the engine as
soon as it is safe to do so and allow it to cool for
10 minutes.
The electrical circuit of the warning light can be
checked by turning the key to “ ” (on). The
warning light should come on for a few seconds,
and then go off.
If the warning light does not come on initially when
the key is turned to “ ” (on), or if the warning
light remains on, have a Yamaha dealer check the
vehicle.NOTICEECB00011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.
EBU29933Fuel 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). The warning light
should come on for a few seconds, and then go
off.
If the warning light does not come on initially when
the key is turned to “ ” (on), or if the warning
light remains on, have a Yamaha dealer check the
electrical circuit.EBU29943Engine trouble warning light “ ”
This warning light comes on or flashes when an
electrical circuit monitoring the engine is not work-
ing correctly. 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). The
warning light should come on for a few seconds,
and then go off.
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If the warning light does not come on initially when
the key is turned to “ ” (on), or if the warning
light remains on, have a Yamaha dealer check the
electrical circuit.
EBU18067Handlebar switchesEBU18081Engine 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 situa-
tion. The engine will not start or run when this
switch is set to “ ”.
EBU18102Start 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.EBU18157Light 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.NOTICEECB00046Do not use the headlights with the engine
turned off for an extended period of time. The
battery may discharge to the point that the
starter will not have enough power to crank the
engine. If this should happen, remove the bat-
tery and recharge it. (See page 8-42.)
1. Light switch “ / /OFF”
2. Engine stop switch “ / ”
3. Start switch “ ”
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EBU18284Throttle leverPush the throttle lever to increase engine speed
and the speed of the ATV. Because the throttle is
spring-loaded, the ATV will decelerate and the en-
gine will return to an idle any time the throttle lever
is released.TIPBefore 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.
EBU18325Speed limiterThe speed limiter keeps the throttle from fully
opening, even when the throttle lever is pushed to
the maximum.
Adjusting the speed limiter1. Loosen the locknut.
2. To increase the maximum engine poweravailable and the maximum speed of the ATV,
turn the adjusting screw in direction (a). To
decrease the maximum engine power avail-
able and the maximum speed of the ATV, turn
1. Throttle lever
1
1. Locknut
2. Adjusting screw
3. No more than 12 mm (0.47 in)
3
12
(a)
(b)
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4The brake lever is located on the right handlebar.
To apply the front brake, pull the brake lever to-
ward the handlebar grip.
The brake lever is equipped with a position adjust-
ing bolt. To adjust the distance between the brake
lever and the handlebar grip, hold the brake lever
away from the handlebar so it does not contact
the adjusting bolt, loosen the locknut, turn the ad-
justing bolt, and then tighten the locknut.
EBU18434Brake pedal
The brake pedal is located on the right side of the
ATV. To apply the rear brake, push down on the
brake pedal.EBU18521Parking brake leverUse 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)
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WARNING
EWB00221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.
EBU18532Shift pedalThe shift pedal is located on the left side of the en-
gine and is used in combination with the clutch
when shifting. (See page 6-2.)
1. Parking brake lever (unlocked position)
1. Shift pedal
1
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EBU18722Fuel tank capRemove the fuel tank cap by turning it counter-
clockwise.EBU37251FuelMake sure there is sufficient gasoline in the tank
before starting off. This model has been designed
to use premium unleaded gasoline of RON 97. If
knocking or pinging occurs, use a gasoline of a
higher octane (research octane number) or a dif-
ferent brand. Use of unleaded fuel will extend
spark plug life and reduce maintenance costs.
WARNING
EWB02522Gasoline 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
of sparks, open flames, or other sources of
ignition such as the pilot lights of water heat-
ers and clothes dryers.
2. When refueling, be sure to select the recom- mended fuel as specified. Do not overfill the
fuel tank. Since fuel expands when heated,
stop filling when the fuel reaches the bottom
of the filler tube. Otherwise heat from the en-
gine or sun can cause the fuel to expand and
spill out of the fuel tank.
1. Fuel tank cap
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TIPWhen refueling, check that the gasoline pump
nozzle has the same identification mark. NOTICEECB00071Use 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.
1. Maximum fuel level
2. Fuel tank filler tubeRecommended fuel:Premium unleaded gasoline, octane 97 or
higher
Fuel tank capacity: 10.0 L (2.64 US gal, 2.20 Imp.gal)
Fuel reserve amount: 3.4 L (0.90 US gal, 0.75 Imp.gal)
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1. EN228 fuel identification mark
E10
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