2002 YAMAHA YFM80 engine

4-7
EBU00063
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.
q
1. Throttle lever1. Levier d’accélérateur1. Palanca del aceleración
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4-9
EBU00561
Speed limiter
The speed limiter keeps the throttle from fully
opening, even when the throttle lever is pushed
to the maximum. Screwing in the adjuster 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 speed adjuster out more than 15
mm or the throttle cable could be damaged.
qw a
1. Locknut 2. Adjuster a. 15 mm1. Contre-écrou 2. Dispositif de réglage1. Contratuerca 2. Ajustador
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4-15
EBU00075
Parking brake
Use the parking brake when you have to start
the engine or park the machine, especially on a
slope. Apply the rear brake lever and push down
the lock plate to apply the parking brake.
Squeeze the rear brake lever to release the
parking brake.
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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.
q
1. Lock plate1. Plaque de verrouillage1. Placa de bloqueo
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4-17
EBU00083
Shift pedal
This machine is equipped with a constant-mesh
3-speed transmission. The shift pedal is located
on the left side of the engine. Neutral is at the
bottom position.
EBU00092
Fuel tank cap
Remove the fuel tank cap by turning it counter-
clockwise.
q
3
2
1
N
q
1. Shift pedal N. Neutral1. Pédale de sélection N. Point mort1. Pedal del cambio N. Punto muerto
1. Fuel tank cap
1. Bouchon de réservoir de carburant
1. Tapón del depósito de combustible
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4-19
EBU00093
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, return the fuel cock lever to the
“ON” position.
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4-21
EBU00096
Choke lever
The choke is used to start a cold engine. Refer
to “Starting a cold engine” for proper operation.
(See page 6-3.)
q
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ea
a. Choke lever 2. Half open (Warming up position)
1. Fully open “ON” 3. Closed “OFF”
a. Levier de choke 2. Mi-course (Position de chauffe)1. Pleine course “ON” 3. Fermé “OFF”
a. Palanca del starter
1. Abierto completamente “ON”
2. Semiabierto (Posición de calentamiento)
3. Cerrado “OFF”
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5-1
EBU00113
PRE-OPERATION CHECKS
Before using this machine, check the following points:
ITEM ROUTINE PAGE
Brakes9Check operation, condition and free play.
5-5~ 5-7, 8-39 ~ 8-47
9Adjust if necessary.
Fuel9Check fuel level.
9Fill with fuel if necessary.5-9 ~ 5-11
Engine oil9Check oil level.
9Fill with oil if necessary.5-11 ~ 5-15, 8-13 ~ 8-17
Final gear oil9Check for leakage. 5-15, 8-19 ~ 8-21
Throttle9Check for proper throttle cable operation. 5-17
Wheels and tires9Check tire pressure, wear and damage. 5-19 ~ 5-25, 8-55
Fittings and fasteners9Check all fittings and fasteners. 5-17
Battery9Check fluid level.
5-17, 8-57 ~ 8-63
9Fill with distilled water if necessary.
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5-9
EBU00909
Fuel
Make sure there is sufficient gasoline in the
tank.
NOTE:
(for Europe only)
If knocking or pinging occurs, use a different
brand of gasoline or higher octane grade.
cC
Use only unleaded gasoline. The use of lead-
ed gasoline will cause severe damage to the
engine internal parts such as valves, piston
rings, exhaust system, etc.
Recommended fuel: Regular gasoline
For Europe: Regular unleaded gasoline
only with a research octane
number of 91 or higher.
For Australia: Unleaded gasoline only
Fuel tank capacity:
Total:
6.8L
Reserve:
0.9 L
1. Filler tube 2. Fuel level1. Tube de remplissage 2. Niveau de carburant1. Tubo de llenado 2. Nivel de combustible
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