2008 YAMAHA YFM80R engine

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Select a large, flat, unpaved area to become famil-
iar with your ATV. Make sure that this area is free
of obstacles and other riders. You should practice
control of the throttle, brakes, shifting procedures,
and turning techniques in this area before trying
more difficult terrain. Always avoid riding on paved
surfaces: the ATV is designed for use on unpaved
surfaces only, and handling maneuvers are more
difficult to perform on pavement.
Set the parking brake and follow the instruction on
page 6-1 to start the engine. Once it has warmed
up you are ready to begin riding your ATV. As you
get on the ATV, be sure not to accidentally move
the shift pedal. Remember that the engine and ex-
haust pipe will be hot when riding and afterwards;
do not allow skin or clothing to come in contact withthese components.
With the engine idling, lift the shift pedal to the 1st
gear position and then release the parking brake.
Apply the throttle slowly and smoothly. The centrif-
ugal clutch will engage and you will start to accel-
erate. Once the ATV has attained adequate
speed, release the throttle and lift the shift pedal to
the 2nd gear position. Release the shift pedal and
apply the throttle smoothly. Use this same proce-
dure as you move into the higher gears. Be sure to
coordinate the use of the throttle and shift pedal
properly. If the throttle is applied too abruptly or if
the throttle is not released during shifting, or if the
shift pedal is not released before applying the
throttle, the front wheels may lift off the ground, re-
sulting in a loss of directional control. Avoid higher
speeds until you are thoroughly familiar with the
operation of your ATV.
CAUTION:
ECB00230
Do not shift gears without releasing the throt-
tle. Damage to the engine or drive train may oc-
cur.
When slowing down or stopping, release the throt-
tle and apply the brakes smoothly and evenly. As
you slow down, shift to a lower gear. Be sure that

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the engine has sufficiently slowed before engaging
a lower gear. Improper use of the brakes or shifting
can cause the tires to lose traction, reducing con-
trol and increasing the possibility of an accident.
WARNING

EWB01560
Make sure the engine has sufficiently slowed
before shifting to a lower gear. Engaging a low-
er gear when the engine speed is too high
could cause the wheels to stop rotating.
TURNING YOUR ATV
To achieve maximum traction on unpaved surfac-
es, the two rear wheels are mounted solidly on one
axle and turn together at the same speed. There-
fore, unless the wheel on the inside of the turn is al-
lowed to slip or lose some traction, the ATV will
resist turning. A special turning technique must be
used to allow the ATV to make turns quickly and
easily. It is essential that this skill be learned first at
low speed.
WARNING

EWB01570
Always follow proper procedures for turning
as described in this Owner’s Manual. Practice
turning at low speeds before attempting to turnat faster speeds. Do not turn at speeds too fast
for your skills or the conditions.
As you approach a curve, slow down and begin to
turn the handlebars in the desired direction. As you
do so, put your weight on the footboard to the out-
side of the turn (opposite your desired direction)
and lean your upper body into the turn. Use the
throttle to maintain an even speed through the
turn. This maneuver will let the wheel on the inside
of the turn slip slightly, allowing the ATV to make
the turn properly.

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EBU28781
PERIODIC MAINTENANCE AND MINOR REPAIR
EBU21670
Safety is an obligation of the owner. Periodic in-
spection, adjustment and lubrication will keep your
ATV in the safest and best operating condition
possible. The most important points of inspection,
adjustment, and lubrication are explained on the
following pages.
The intervals given in the periodic maintenance
and lubrication chart should be considered as a
general guide under normal riding conditions.
However, DEPENDING ON THE WEATHER,
TERRAIN, GEOGRAPHICAL LOCATION, AND
INDIVIDUAL USE, THE MAINTENANCE INTER-
VALS MAY NEED TO BE SHORTENED.
WARNING

EWB01840
Never service an engine while it is running.
Moving parts can catch clothing or parts of the
body, causing injury. Electrical components
can cause shocks or start fires. Turn off the en-
gine when performing maintenance unless
otherwise specified. Have a Yamaha dealer
perform the service if you are not familiar with
maintenance work.
EBU27110
Owner’s manual and tool kit
Be sure to put this owner’s manual in the plastic
bag and to always carry it as well as the owner’s
tool kit and the low-pressure tire gauge in their re-
spective compartments under the seat.
1. Owner’s manual
2. Low-pressure tire gauge
3. Owner’s tool kit
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2

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EBU21742
Periodic maintenance chart for the emission control system
NOTE:


For ATVs not equipped with an odometer or an hour meter, follow the month maintenance intervals.

For ATVs equipped with an odometer or an hour meter, follow the km (mi) or hours maintenance inter-
vals. However, keep in mind that if the ATV isn’t used for a long period of time, the month maintenance
intervals should be followed.

Items marked with an asterisk should be performed by a Yamaha dealer as they require special tools,
data and technical skills.
NO. ITEMCHECK OR MAINTENANCE
JOBINITIAL EVERY
Whichev-
er comes
firstmonth136612
km
(mi)320
(200)1300
(800)2500
(1600)2500
(1600)5000
(3200)
hours 20 80 160 160 3201
*
Fuel line


Check fuel hoses for cracks or other damage, and
replace if necessary.
√√√
2 Spark plug

Check condition and clean, regap, or replace if
necessary.
√√√√√
3
*
Valves


Check valve clearance and adjust if necessary.
√ √√√
4
*
Carburetor


Check choke operation and correct if necessary.

Check engine idling speed and adjust if neces-
sary.
√√√√
5
*
Crankcase breather
system


Check breather hose for cracks or other damage,
and replace if necessary.
√√√

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10
*
Shock absorber
assemblies

Check operation and correct if necessary.

Check for oil leakage and replace if necessary.
√√√
11
*
Front knuckle piv-
ots


Lubricate with lithium-soap-based grease.
√√√
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*
Steering shaft


Lubricate with lithium-soap-based grease.
√√√
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*
Steering system


Check operation and repair or replace if damaged.

Check toe-in and adjust if necessary.
√√√√√
14 Engine oil

Change.

Check ATV for oil leakage, and correct if neces-
sary.
√ √√√
15 Final gear oil

Change.

Check ATV for oil leakage, and correct if neces-
sary.
√√
16
*
Moving parts and
cables


Lubricate.
√√√√
17
*
Throttle lever hous-
ing and cable


Check operation and correct if necessary.

Check throttle cable free play and have a Yamaha
dealer adjust if necessary.

Lubricate throttle lever housing and cable.
√√√√√
18
*
Front and rear brake
switches


Check operation and correct if necessary.
√√√√√
19
*
Battery


Check electrolyte level and specific gravity, and
correct if necessary.

Make sure that the breather hose is properly
routed.
√√√√√
NO. ITEMCHECK OR MAINTENANCE
JOBINITIAL EVERY
Whichev-
er comes
firstmonth 1 3 6 6 12
km
(mi)320
(200)1300
(800)2500
(1600)2500
(1600)5000
(3200)
hours 20 80 160 160 320

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EBU23211
Checking the spark plug
The spark plug is an important engine component,
which is easy to check. Since heat and deposits
will cause any spark plug to slowly erode, the spark
plug should be removed and checked in accor-
dance with the periodic maintenance and lubrica-
tion chart. In addition, the condition of the spark
plug can reveal the condition of the engine.
To remove the spark plug
1. Remove the spark plug cap.
2. Remove the spark plug as shown, with thespark plug wrench included in the owner’s tool
kit.
To check the spark plug
1. Check that the porcelain insulator around the
center electrode of the spark plug is a medi-
um-to-light tan (the ideal color when the ATV
is ridden normally).NOTE:

If the spark plug shows a distinctly different color,
the engine could be operating improperly. Do not
attempt to diagnose such problems yourself. In-
stead, have a Yamaha dealer check the ATV.
1. Spark plug cap
1

1. Spark plug wrench
1

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2. Check the spark plug for electrode erosion
and excessive carbon or other deposits, and
replace it if necessary.
To install the spark plug
1. Measure the spark plug gap with a wire thick-
ness gauge and, if necessary, adjust the gap
to specification.2. Clean the surface of the spark plug gasket
and its mating surface, and then wipe off any
grime from the spark plug threads.
3. Install the spark plug with the spark plug
wrench, and then tighten it to the specified
torque.
NOTE:
If a torque wrench is not available when installing
a spark plug, a good estimate of the correct torque
is 1/4–1/2 turn past finger tight. However, the spark
plug should be tightened to the specified torque as
soon as possible.
4. Install the spark plug cap.
EBU23253
Engine oil
The engine oil level should be checked before
each ride. In addition, the oil must be changed at
the intervals specified in the periodic maintenance
and lubrication chart. Specified spark plug:
NGK/CR7HSA
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)
1. Spark plug gap
Tightening torque:
Spark plug:
12.5 Nm (1.3 m·kgf, 9.0 ft·lbf)

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To check the engine oil level
1. Place the ATV on a level surface.
2. Check the engine oil level on a cold engine.
NOTE:

If the engine was started before checking the oil
level, be sure to warm up the engine sufficiently,
and then wait at least ten minutes until the oil set-
tles for an accurate reading.
3. Remove the engine oil filler cap, and then
wipe the dipstick off with a clean rag.
4. Insert the dipstick into the filler hole (without
screwing it in), and then remove it again tocheck the oil level.NOTE:
The engine oil should be between the minimum
and maximum level marks.
5. If the engine oil is at or below the minimum
level mark, add sufficient oil of the recom-
mended type to raise it to the correct level.
6. Insert the dipstick into the oil filler hole, and
then tighten the engine oil filler cap.
1. Engine oil filler cap
1

1. Dipstick
2. Maximum level mark
3. Minimum level mark
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