engine YAMAHA YFZ450 2006 User Guide

4-9
EBU11580
Engine stop switch “ENG. STOP”
Make sure that the engine stop switch is in the
“RUN” position before starting the engine. The
engine 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”.1
2
3
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 paro del motor “ENG. STOP”
3. Interruptor de arranque “START”
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4-11
1. Throttle lever1. Levier d’accélération1. Palanca del aceleración
EBU00630
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 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.
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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. Pas plus que 12 mm
1. Contratuerca 2. Tornillo de ajuste
a. No más de 12 mm
EBU11980
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
decreases the maximum speed of the ATV.
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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 dam-
aged. Always make sure the throttle lever
free play is adjusted to 2–4 mm. See page
8-79.
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4-15
1. Clutch lever1. Levier d’embrayage1. Palanca de embrague
EBU00690
Clutch lever
The clutch lever is located on the left handlebar
and the ignition circuit cut-off system is incorpo-
rated 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 system.)
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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)
EBU14072
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.
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8Always 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 con-
trol or a collision.
8Always 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.
5TG-9-62 4 5/12/05 5:18 PM Page 4-19

4-21
1. Shift pedal1. Pédale de sélection1. Pedal del cambio
1. Fuel tank cap
1. Bouchon de réservoir de carburant1. Tapón del depósito de combustible
EBU00820
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 com-
bination 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
EBU00930
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 posi-
tion 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 posi-
tion. THEN FILL THE FUEL TANK AT THE
FIRST OPPORTUNITY. After refuelling,
return the fuel cock lever to the “ON” posi-
tion.
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4-25
EBU00950
Starter (choke) “1”
Starting a cold engine requires a richer air-fuel
mixture. A separate starter circuit supplies this
mixture.
Move in direction ato turn on the starter
(choke).
Move in direction bto turn off the starter
(choke).
Refer to “Starting a cold engine” for proper oper-
ation. (See page 6-3.)
1. Starter (choke) “1”1. Starter (enrichisseur) “1”1. Starter (choke) “1”
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5-1
EBU01130
PRE-OPERATION CHECKS
Before using this machine, check the following points:
ITEM ROUTINE PAGE
Front brake9Check operation lever, free play, fluid level and fluid leakage. 5-7–5-11, 8-81,
9Fill with DOT 4 brake fluid if necessary. 8-85–8-91
Rear brake9Check operation, fluid level and fluid leakage. 5-7–5-11
9Fill with DOT 4 brake fluid if necessary. 8-83–8-89, 8-93
Clutch9Check operation, condition and lever free play. 8-103
Parking brake9Check operation, condition and cable length. 8-97–8-99
Fuel 9Check fuel level.
9Fill with fuel if necessary.5-13–5-15
Engine oil9Check oil level.
9Fill with oil if necessary.5-17, 8-25–8-41
Coolant reservoir 9Check coolant level in reservoir.
9Fill with coolant if necessary.5-19–5-21, 8-43–8-53
Drive chain9Check chain slack and condition.
9Adjust if necessary.5-21, 8-105–8-113
Throttle9Check for proper throttle cable operation and free play. 5-21, 8-79
Wheels and tires9Check tire pressure, wear and damage. 5-23–5-29, 8-125–8-127
Fittings and fasteners9Check all fittings and fasteners. 5-29
Lights and switches9Check for proper operation. 5-29, 8-99, 8-137–8-141
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5-13
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.
cC
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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