2002 YAMAHA YFM80 engine

5-11
w
8Do not overfill the fuel tank. Fuel expands
when it heats up. If the fuel tank is over-
filled, fuel could spill out due to heat from
the engine or the sun.
8Be careful not to spill fuel, especially on
the engine or exhaust pipe which can
cause a fire and severe injury. Wipe up
any spilled fuel immediately.
8Do not refuel right after the engine has
been running and is still very hot.
8Be sure the fuel tank cap is closed secure-
ly.
EBU00445
Engine oil
Make sure the engine oil is at the specified level.
Add oil as necessary. (See page 8-13 for
details.)
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5-13
cC
Be sure to use motor oils that do not contain
anti-friction modifiers. Passenger car motor
oils (often labeled “Energy Conserving”)
contain anti-friction additives which will
cause clutch and/or starter clutch slippage,
resulting in reduced component life and poor
engine performance.
Recommended oil:
Recommended engine oil classification:
API Service SE, SF, SG type or higher
–20° 10° 20° 30° 40°
10W30
10W40
20W40
20W5050°C
0° –10°
5W30
15W40
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5-17
EBU00151
Throttle lever
Check to see that the throttle lever operates cor-
rectly. It must open smoothly and spring back to
idle position when released. Repair as neces-
sary for proper operation.
EBU00152
Fittings and Fasteners
Always check the tightness of chassis fittings
and fasteners before a ride. Take the machine
to a Yamaha dealer or refer to the Service
Manual for correct tightening torque.
EBU00154
Switches
Check the operation of the start switch, engine
stop switch and any other switches. Repair as
necessary for proper operation.
EBU00499
Battery
Check fluid level and fill if necessary. Use only
distilled water if refilling is necessary. (See
pages 8-57 ~ 8-63.)
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6-3
EBU00580
Starting a cold engine
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Always make sure all control cables work
smoothly before you begin riding in cold
weather. If the control cables are frozen or
do not work smoothly, you could be unable
to control the ATV, which could lead to an
accident or collision.
1. Set the parking brake.
2. Turn the fuel cock to “ON”.
3. Turn the main switch to “ON” and the
engine stop switch to “RUN”.
4. Shift the transmission into neutral.
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6-5
NOTE:
This model is equipped with an ignition circuit
cut-off system.
The engine can be started under the following
conditions.
a. When the transmission is in neutral. At this
time the neutral indicator light should come
on. If the light does not come on, ask a
Yamaha dealer to inspect it.
b. When the transmission is in gear and the
rear brake lever is applied. However, it is
recommended to shift into neutral before
starting the engine.
5. Use the choke lever in reference to the fig-
ure:
Position 1: Cold engine start-
ambient temperature below 30°C.
Position 2: Warming up position.
Position 3: Cold engine start-
ambient temperature above 25°C
and warm engine start position.
CHOKE
ON
O
F
F
q
we q
e
0°10°20°30°
°C
a
1. Fully open “ON”2. Half open (Warming up position)
3. Closed “OFF”a. Choke lever
1. Pleine course “ON”2. Mi-course (Position de chauffe)3. Fermé “OFF”a. Levier de choke
1. Abierto completamente “ON”
2. Semiabierto (Posición de calentamiento)
3. Cerrado “OFF”a. Palanca del starter AMBIENT TEMP. / CHOKE LEVER POSITION
POSITION DE LEVIER DE STARTER / TEMP. AMBIANTEPOSICION DEL MANDO DEL STARTER / TEMP. AMBIENTE
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6-7
6. Completely close the throttle lever and
start the engine by pushing the start
switch.
NOTE:
If the engine fails to start, release the start
switch, then push it again. Pause a few seconds
before the next attempt. Each cranking should
be as short as possible to preserve battery ener-
gy. Do not crank the engine more than 10 sec-
onds on each attempt.
7. If the engine is started with the starter
(choke) in position 1, the choke lever
should be returned to position 2to warm
up the engine. If the engine is started with
the starter (choke) in position 2, keep the
starter (choke) in this position to warm up
the engine.
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6-9
8. Continue warming up the engine until it
idles smoothly and return the choke lever
to position 3before riding.
cC
See the “Engine break-in” section prior to
operating engine for the first time.
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6-11
EBU00181
Starting a warm engine
To start a warm engine, refer to the “Starting a
cold engine” section. The choke lever should not
be used. The throttle should be opened slightly.
EBU00184
Warming up
To get maximum engine life, always warm up
the engine before starting off. Never accelerate
hard with a cold engine! To see whether or not
the engine is warm, check if it responds to the
throttle normally with the choke lever turned off.
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