engine YAMAHA YFZ450 2005 User Guide

4-9 1. Light switch “LIGHTS”
2. Engine stop switch “ENG. STOP”
3. Start switch “START”
1. Contacteur d’éclairage “LIGHTS”
2. Coupe-circuit du moteur “ENG. STOP”
3. Contacteur du démarreur “START”
1. Interruptor de luces “LIGHTS”
2. Interruptor de parada del motor “ENG. STOP”
3. Interruptor de arranque “START”
EBU11580
Engine stop switch “ENG. STOP”
Make sure that the engine stop switch is in the
“RUN” position before starting the engine. The en-
gine stop switch controls ignition and can be used
at all times to stop the engine, especially in an
emergency. The engine will not start or run when
the engine stop switch is turned to “OFF”.
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4-11 1. Throttle lever
1. Levier d’accélération
1. Palanca de aceleración
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Throttle lever
Once the engine is running, movement of the
throttle lever will increase the engine speed.
Regulate the speed of the machine by varying the
throttle position. Because the throttle is spring-
loaded, the machine will decelerate, and the en-
gine will return to an idle any time the hand is re-
moved 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
_ 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
operation of the throttle lever before you start
the engine. If the throttle does not work
smoothly, check for the cause. Correct the
problem before riding the ATV or consult a
Yamaha dealer. _
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4-13 1. Locknut 2. Adjusting screw
a. No more than 12 mm
1. Contre-écrou 2. Vis de réglage
a. 12 mm maximum
1. Contratuerca 2. Tornillo de ajuste
a. 12 mm como máximo
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Speed limiter
The speed limiter keeps the throttle from fully
opening, even when the throttle lever is pushed to
the maximum. Turning in the adjusting screw limits
the maximum engine power available and de-
creases the maximum speed of the ATV.
WARNING
_ 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
or the throttle cable could be damaged. Always
make sure the throttle lever free play is adjust-
ed to 2–4 mm. See page 8-77. _
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4-15 1. Clutch lever
1. Levier d’embrayage
1. Palanca de embrague
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Clutch lever
The clutch lever is located on the left handlebar
and the ignition circuit cut-off system is incorporat-
ed in the clutch lever holder. Pull the clutch lever to
the handlebar to disengage the clutch, and release
the lever to engage the clutch. The lever should be
pulled rapidly and released slowly for smooth
clutch operation. (Refer to “Starting a cold engine”
for a description of the ignition circuit cut-off sys-
tem.)
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4-19 1. Parking brake lever (Locked position)
1. Levier de frein de stationnement (frein serré)
1. Palanca del freno de estacionamiento (posición de bloqueo)
1. Parking brake lever (Unlocked position)
1. Levier de frein de stationnement (frein relâché)
1. Palanca del freno de estacionamiento
(posición de desbloqueo)
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Parking brake lever
Use the parking brake when you have to start the
engine or park the machine, 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.
WARNING
_

Always set the parking brake before start-
ing the engine. The ATV could start mov-
ing unexpectedly if the parking brake is not
applied. This could cause loss of control or
a collision.


Always be sure you have released the
parking brake before you begin to ride. The
brake could overheat if you ride the ATV
without releasing the parking brake. You
could lose braking performance which
could cause an accident. You could also
wear out the brakes prematurely.
_
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4-21 1. Shift pedal
1. Pédale de sélection
1. Pedal del cambio
1. Fuel tank cap
1. Bouchon du réservoir de carburant
1. Tapón del depósito de combustible
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Shift pedal
This machine 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 combi-
nation with the clutch when shifting.
EBU00920
Fuel tank cap
Remove the fuel tank cap by turning it counter-
clockwise.
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4-23
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Fuel cock
The fuel cock supplies fuel from the fuel tank to the
carburetor.
The fuel cock has three positions.
OFF: With the lever in this position, fuel will not
flow. Always turn the lever to this position
when the engine is not running.
ON: With the lever in this position, fuel flows to
the carburetor. Normal riding is done with
the lever in this position.
RES: This indicates reserve. If you run out of fuel
while riding, turn the lever to this position.
THEN FILL THE FUEL TANK AT THE
FIRST OPPORTUNITY. After refuelling, re-
turn the fuel cock lever to the “ON” position.
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4-25 1. Starter (choke) “”
1. Starter (enrichisseur) “”
1. Starter (choke) “”
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Starter (choke) “”
Starting a cold engine requires a richer air-fuel
mixture. A separate starter circuit supplies this
mixture.
Move in direction
a to turn on the starter (choke).
Move in direction
b to turn off the starter (choke).
Refer to “Starting a cold engine” for proper opera-
tion. (See page 6-3.)
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5-1
EBU01130
1-PRE-OPERATION CHECKS
Before using this machine, check the following points:
ITEM ROUTINE PAGE
Front brakeCheck operation, lever free play, fluid level and fluid leakage.
Fill with DOT 4 brake fluid if necessary.5-5–5-7, 8-79,
8-83–8-89
Rear brakeCheck operation, fluid level and fluid leakage.
Fill with DOT 4 brake fluid if necessary.5-5–5-7,
8-81–8-87, 8-91
ClutchCheck operation, condition and lever free play. 8-99
Parking brakeCheck operation, condition and cable length. 8-93–8-95
FuelCheck fuel level.
Fill with fuel if necessary.5-9–5-11
Engine oilCheck oil level.
Fill with oil if necessary.5-13, 8-23–8-39
Coolant reservoirCheck coolant level in reservoir.
Fill with coolant if necessary.5-15–5-17,
8-41–8-51
Drive chainCheck chain slack and condition.
Adjust if necessary.5-17, 8-101–8-109
ThrottleCheck for proper throttle cable operation and free play. 5-17, 8-77
Wheels and tiresCheck tire pressure, wear and damage.5-21–5-27,
8-121–8-123
Fittings and fastenersCheck all fittings and fasteners. 5-19
Lights and switchesCheck for proper operation.5-19, 8-97,
8-133–8-141
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5-9
EBU14571
Fuel
Make sure there is sufficient gasoline in the tank.NOTE:_ If knocking or pinging occurs, use a different brand
of gasoline or higher octane grade. _CAUTION:_ 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. _
Recommended fuel:
PREMIUM UNLEADED GASOLINE ONLY
For Europe:
PREMIUM UNLEADED GASOLINE
ONLY with a research octane number of
97 or higher
Fuel tank capacity:
Total:
10.0 L
Reserve:
1.9 L
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