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EBU29090
Read this manual carefully before operating this vehicle. This manual should stay with this ve-
hicle if it is sold.
EC Declaration of Conformityconforming to Directive
98/37/EC
(
Make, model)
to which this declaration applies, conforms to the essential health
and safety requirements of Directive 98
/37/EC,
and to the other relevant Directives of EEC
89/336/EEC or 2004
/108/EC
(
Title and
/or number and date of issue of the other Directives of EEC)
(
If applicable)
(
If applicable)To e
ffect correct
application
of the
essential
health
and safety
requirements
stated in the Directives of EEC, the
following-standards and
/or technical
specifications were consulted:
EN292 ANSI
/SVIA 1-2007
(
Title and
/or number and date of issue of standards and
/or specifications)
General Manager
RV Engineering Division
RV Company Signature
Date of Issue
Shinya Shimada2 March, 2008
YAMAHA MOTOR EUROPE N.V.
Koolhovenlaan 101, 1119NC Schiphol-Rijk, The Netherlands
We, YAMAHA MOTOR CO., LTD. 2500 Shingai, Iwata, Japan,
Authorized Representativedeclare in sole responsibility, that the product
YFM50 (
YFM50R) (
JY4AA01W080004151
~ )
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jacket, and long pants.
Never consume alcohol or drugs before or while
operating this ATV.
Never operate at speeds too fast for your skills
or the riding conditions. Always go at a speed
that is proper for the terrain, visibility, operating
conditions, and your experience.
Never attempt wheelies, jumps, or other stunts.
Always inspect your ATV each time you use it to
make sure it is in safe operating condition. Al-
ways follow the inspection and maintenance
procedures and schedules described in this
manual.
Always keep both hands on the handlebars and
both feet on the footrests of the ATV during op-
eration.
Always go slowly and be extra careful when op-
erating on unfamiliar terrain. Always be alert to
changing terrain conditions when operating the
ATV.
Never operate on excessively rough, slippery or
loose terrain until you have learned and prac-
ticed the skills necessary to control the ATV on
such terrain. Always be especially cautious on
these kinds of terrain.
Always follow proper procedures for turning asdescribed in this manual. Practice turning at low
speeds before attempting to turn at faster
speeds and never turn at excessive speeds.
Never operate the ATV on hills too steep for the
ATV or for your abilities. Practice on smaller hills
before attempting larger hills.
Always follow proper procedures for climbing
hills as described in this manual. Check the ter-
rain carefully before you start up any hill. Never
climb hills with excessively slippery or loose sur-
faces. Shift your weight forward. Never open the
throttle suddenly or make sudden gear changes.
Never go over the top of a hill at high speed.
Always follow proper procedures for going down
hills and for braking on hills as described in this
manual. Check the terrain carefully before you
start down any hill. Shift your weight backward.
Never go down a hill at high speed. Avoid going
down a hill at an angle that would cause the ve-
hicle to lean sharply to one side. Go straight
down the hill where possible.
Always follow proper procedures for crossing
the side of a hill as described in this manual.
Avoid hills with excessively slippery or loose sur-
faces. Shift your weight to the uphill side of the
ATV. Never attempt to turn the ATV around on
Page 29 of 116
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mm (0.47 in) or the throttle cable could be dam-
aged.
EBU18391
Front brake lever
The front brake lever is located on the right handle-
bar. To apply the front brake, pull the brake lever
toward the handlebar grip.
EBU18401
Rear brake lever
The rear brake lever is located on the left handle-
bar. To apply the rear brake, pull the brake lever to-
ward the handlebar grip.
EBU18460
Parking brake
Use the parking brake before starting the engine or
parking the ATV, 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.
1. Front brake lever
1
1. Rear brake lever
1
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of gasoline or higher octane grade.
NOTICE
ECB00070
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.
WARNING
EWB00310
Do not overfill the fuel tank. Fuel expands
when it heats up. If the fuel tank is overfilled,
fuel could spill out due to heat from the en-
gine or the sun.
Be 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.
Do not refuel right after the engine has been
running and is still very hot.
Be sure the fuel tank cap is closed securely.
EBU18820
Fuel cock
The fuel cock supplies fuel from the tank to the car-
buretor while also filtering it.The fuel cock lever positions are explained as fol-
lows and shown in the illustrations.
OFF
With the fuel cock lever in this position, fuel will not
flow. Always turn the fuel cock lever to this position
when the engine is not running.
1. Arrow mark positioned over “OFF”
RES
ONFUEL
OFF
1
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EBU19540
Fuel
Make sure that there is sufficient fuel in the tank.
(See page 4-8.)
WARNING
EWB00520
Do not overfill the fuel tank. Fuel expands
when it heats up. If the fuel tank is overfilled,
fuel could spill out due to heat from the en-
gine or the sun.
Be 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.
Do not refuel right after the engine has been
running and is still very hot.
Be sure the fuel tank cap is closed securely.
EBU19560
Engine oil
Make sure that the engine oil is at the specified lev-
el. Add oil as necessary. (See page 8-9.)
EBU19590
Final gear oil
Make sure that the final gear oil is at the specified
level. Add oil as necessary. (See page 8-12.)
EBU19650
Front and rear brakes
Brake levers
Check for correct free play in the brake levers. If
the free play is incorrect, adjust it. (See pages
8-21 and 8-23.)
Check operation of the levers. They should
move smoothly and there should be a firm feel-
ing when the brake is applied. If not, have the
ATV checked by a Yamaha dealer.
Brake operation
Test the brakes at slow speed after starting out to
make sure they are working properly. If the brakes
do not provide proper braking performance, check
the brakes for wear. (See page 8-20.)
WARNING
EWB00570
Always check the brakes at the start of every
ride. Do not ride the ATV if you find any prob-
lem with the brakes or you could lose braking
ability, which could lead to an accident. If a
problem cannot be corrected by the adjust-
ment procedures provided in this manual, have
the ATV checked by a Yamaha dealer.
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crank the engine more than 10 seconds on each
attempt.
7. If the engine is started with the choke in posi-
tion (1), the choke should be returned to posi-
tion (2) to warm up the engine. If the engine is
started with the choke in position (2), keep the
choke in this position to warm up the engine.
NOTICE
ECB00160
For maximum engine life, always warm the en-
gine up before starting off. Never accelerate
hard when the engine is cold!
8. Continue warming up the engine until it idles
smoothly, then return the choke to position (3)
before riding.
TIP
The engine is warm when it responds normally to
the throttle with the choke turned off.
EBU20301
Starting a warm engine
Follow the same procedure as for starting a cold
engine, with the exception that the choke is not re-
quired when the engine is warm. Instead, start the
engine with the throttle slightly open.
EBU27880
Shifting
This ATV has an automatic, centrifugal clutch.
To shift into the drive position, release the throttle
lever and apply the parking brake.
To shift into neutral, stop the ATV by releasing the
throttle lever and applying the brakes smoothly
and evenly.
EBU20630
To start out and accelerate
1. Release the throttle lever.
NOTICE
ECB00210
Always close the throttle before shifting the
transmission into drive, otherwise damage to
the engine and drive train may result.
2. Apply the parking brake. (See page 6-5.)
3. Shift the transmission into drive.
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When riding in an area where you might not easily
be seen, such as desert terrain, mount a caution
flag on the ATV. DO NOT use the flag pole bracket
as a trailer hitch.
WARNING
EWB01550
Always mount a caution flag on the ATV to
make you more visible when operating in areas
where you might not be seen by other vehicles.
Watch carefully for other vehicles.
Do not ride in areas posted “no trespassing”.
Do not ride on private property without getting per-
mission.
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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).
TIP
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