fuel YAMAHA YFM90 2017 Owners Manual

EBU17421
TABLE OF CONTENTS
LOCATION OF THE WARNING AND
SPECIFICATION LABELS .............................. 1-1
SAFETY INFORMATION ................................ 2-1
DESCRIPTION................................................ 3-1Left view ...................................................... 3-1
Right view.................................................... 3-1
Controls and instruments............................ 3-2
INSTRUMENT AND CONTROL
FUNCTIONS ................................................... 4-1 Main switch ................................................. 4-1
Indicator lights............................................. 4-1
Handlebar switches .................................... 4-2
Throttle lever ............................................... 4-2
Speed limiter ............................................... 4-3
Front brake lever ......................................... 4-4
Rear brake lever .......................................... 4-5
Parking brake .............................................. 4-5
Drive select lever ......................................... 4-6
Kickstarter ................................................... 4-7
Fuel tank cap .............................................. 4-8
Fuel ............................................................. 4-8 Fuel cock .................................................. 4-10
Starter (choke) ......................................... 4-11
Seat .......................................................... 4-12
Adjusting the front shock absorber
assemblies .............................................. 4-13
Adjusting the rear shock absorber assembly ................................................ 4-14
PRE-OPERATION CHECKS .......................... 5-1 Fuel ............................................................. 5-3
Engine oil .................................................... 5-3
Transmission oil .......................................... 5-3
Front and rear brakes ................................. 5-3
Throttle lever ............................................... 5-3
Drive chain .................................................. 5-3
Tires ............................................................ 5-3
Chassis fasteners ....................................... 5-6
Instruments and switches........................... 5-6
OPERATION .................................................. 6-1 Starting a cold engine................................. 6-1
Starting a warm engine............................... 6-3
Operating the drive select lever and driving in reverse ...................................... 6-3UBD361E0.book Page 1 Monday, January 25, 2016 10:53 AM

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1

**.* kPa
*.** kgf/cm²
*.* psi **.* kPa
*.** kgf/cm²
*.* psi
This unit contains high-pressure nitrogen
gas.
Mishandling can cause an explosion. Do not
incinerate, puncture or open.
Use unleaded gasoline only.
Measure the tire pressure when the tires are
cold. Turning the ATV in 4WD-LOCK
(“DIFF.LOCK”) takes more effort.
Operate at a slow speed and allow extra
time and distance for maneuvers to avoid
loss of control. Adjust the tire pressure.
Improper tire pressure can cause loss of
control.
Loss of control can result in severe injury or
death.
This pictogram shows the loading limits
and/or maximum load capacity for this ATV.
Follow all load limits and other loading
guidelines in this manual.
Load may include the driver, passenger,
human protective gear, accessories, goods,
luggage, and all other load related items.
Make sure you do not exceed the load limits.
Overloading can cause loss of control.
Loss of control can result in severe injury or
death.
NEVER store fuel or flammable liquids.
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2-4
2

Never maintain an ATV without proper knowl-
edge. Contact an authorized ATV dealer to in-
form you on basic ATV maintenance. Certain
maintenance can only be carried out by certified
staff.
In the event of an accident 1. If serious injuries are incurred, you may be safer staying next to your vehicle; it may
shield you from oncoming riders. Depending
on your injuries and position in the trail; you
must make a judgment call as to whether you
should move to a position off the trail. If you
have sustained head, neck, or back injuries,
or cannot feel your limbs, you should not
move. Keep your helmet on and remain mo-
tionless. Lie down next to your vehicle and
wait for help.
2. If less serious injuries are incurred and you can walk, then move to a position off the trail.
Check yourself for injuries and apply first aid
as needed.
3. If your injuries are light, when safe to do so, move your vehicle off the trail to avoid colli-
sions with oncoming riders. Check for injuries
and apply first aid as necessary. If you can
physically operate your vehicle, inspect your vehicle. If the vehicle is in safe operating con-
dition and you can safely operate it, restart it
and ride gently back to camp or other known
location where you can receive medical at-
tention. If necessary, contact your riding party
or local authorities to let them know where
you are and what has happened.
In the event of a breakdown 1. If your vehicle will not restart or is not in safe operating condition, turn off the main switch
and engine stop switch. If the breakdown oc-
curs at twilight or night, leave the main switch
on so that your lights may warn other riders of
your stopped vehicle.
2. Get out of danger. Check for oncoming vehi- cles and when safe, push your vehicle to the
side of the trail or even off the main trail to
avoid any possible collisions with oncoming
riders. If you cannot move your vehicle by
yourself, when safe, walk to the nearest van-
tage point and signal an oncoming rider to
help you push your vehicle to a safe place off
the trail.
3. Inspect your vehicle for any immediate haz- ardous conditions. The most obvious hazard-
ous conditions are leaking fuel and
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2-5
2ungrounded or broken wiring. Visually check
for broken wiring and leaking fuel. Leaking
fuel can be confirmed by the odor of gasoline.
4. Once immediate safety hazards are con- firmed not to exist, you may remove your hel-
met to more closely inspect your vehicle.
Check for external signs of wear, broken
parts, fluid leaks, cracks in the frame, sus-
pension damage, wheel damage, and so on.
Fuel, oil, and coolant usually give off a notice-
able odor.
5. If your vehicle will not restart or if it is unsafe to ride, then turn off all vehicle systems (en-
gine stop switch, main switch, and fuel cock),
and then signal or go for help.
Aftermarket Parts, Accessories, and Modifica-
tions
While you may find aftermarket products similar in
design and quality to genuine Yamaha accesso-
ries, recognize that some aftermarket accessories
or modifications are not suitable because of po-
tential safety hazards to you or others. Installing
aftermarket products or having other modifica-
tions performed to your vehicle that change any of
the vehicle’s design or operation characteristics
can put you and others at greater risk of serious injury or death. You are responsible for injuries re-
lated to changes in the vehicle. Keep the following
guidelines in mind, as well as those provided un-
der “Loading” when mounting accessories.

Never install accessories that would impair the
performance of your ATV. Carefully inspect the
accessory before using it to make sure that it
does not in any way reduce ground clearance,
limit suspension travel, steering travel or control
operation.
 Accessories fitted to the ATV can create insta-
bility due to improper weight distribution.
 Bulky or large accessories may seriously affect
the stability of the ATV.
 Certain accessories can displace the operator
from his or her normal riding position. This im-
proper position limits the freedom of movement
of the operator and may limit control ability,
therefore, such accessories are not recom-
mended.
 Use caution when adding electrical accesso-
ries. If electrical accessories exceed the capac-
ity of the ATV’s electrical system, an electric
failure could result, which could cause a dan-
gerous loss of lights or engine power.
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2
WARNING
EWB00073Avoid Carbon Monoxide Poisoning
All engine exhaust contains carbon monoxide,
a deadly gas. Breathing carbon monoxide can
cause headaches, dizziness, drowsiness, nau-
sea, confusion, and eventually death.
Carbon Monoxide is a colorless, odorless,
tasteless gas which may be present even if you
do not see or smell any engine exhaust. Deadly
levels of carbon monoxide can collect rapidly
and you can quickly be overcome and unable
to save yourself. Also, deadly levels of carbon
monoxide can linger for hours or days in en-
closed or poorly ventilated areas. If you experi-
ence any symptoms of carbon monoxide
poisoning, leave the area immediately, get
fresh air, and SEEK MEDICAL TREATMENT.
Do not run engine indoors. Even if you try to
ventilate engine exhaust with fans or open
windows and doors, carbon monoxide can
rapidly reach dangerous levels.
 Do not run engine in poorly ventilated or par-
tially enclosed areas such as barns, garages,
or carports. 
Do not run engine outdoors where engine
exhaust can be drawn into a building through
openings such as windows and doors.

WARNING
EWB02592When transporting the ATV in another vehicle,
be sure it is kept upright and that the fuel cock
is in the “OFF” position. Otherwise, fuel may
leak out of the carburetor or fuel tank.
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3-1
3
EBU17681
DESCRIPTION
EBU17691Left view
EBU17701Right view
1. Fuel tank cap
2. Fuel cock
3. Air filter
4. Fuse
5. Battery
6. Rear shock absorber assembly spring preload adjusting ring
7. Kickstarter lever cap
1 2 3 4,5
76
1. Spark arrester
2. Owner’s tool kit
3. Front shock absorber assembly spring preload adjusting ring
4. Spark plug
5. Engine oil filler cap
6. Transmission oil filler cap
12 3
65 4
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4
NOTICEECB02300Do not use the kickstarter if the battery is not
installed or if the battery leads are not connect-
ed. EBU18721Fuel tank capRemove the fuel tank cap by turning it counter-
clockwise.
EBU18757FuelMake sure there is sufficient gasoline in the tank.
WARNING
EWB02522Gasoline and gasoline vapors are extremely
flammable. To avoid fires and explosions and
to reduce the risk of injury when refueling, fol-
low these instructions. 1. Before refueling, turn off the engine and besure that no one is sitting on the vehicle. Nev-
er refuel while smoking, or while in the vicinity
1. Kickstarter lever
1
1. Fuel tank cap
1
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4-9
4of sparks, open flames, or other sources of
ignition such as the pilot lights of water heat-
ers and clothes dryers.
2. Do not overfill the fuel tank. When refueling, be sure to insert the pump nozzle into the fuel
tank filler hole. Stop filling when the fuel
reaches the bottom of the filler tube. Because
fuel expands when it heats up, heat from the
engine or the sun can cause fuel to spill out of
the fuel tank.
3. Wipe up any spilled fuel immediately.NOTICE: Immediately wipe off spilled fuel
with a clean, dry, soft cloth, since fuel may
deteriorate painted surfaces or plastic
parts.
[ECB00982]
4. Turn the fuel tank cap fully clockwise to make sure it is securely closed.
WARNING
EWB02532Gasoline is poisonous and can cause injury or
death. Handle gasoline with care. Never siphon
gasoline by mouth. If you should swallow some
gasoline or inhale a lot of gasoline vapor, or get
some gasoline in your eyes, see your doctor
1. Maximum fuel level
2. Fuel tank filler tube
12
Recommended fuel:Regular unleaded gasoline only
For Europe: Regular unleaded gasoline only
with a research octane number of 95 or
higher
Fuel tank capacity: 6.6 L (1.74 US gal, 1.45 Imp.gal)
Fuel reserve amount: 0.9 L (0.24 US gal, 0.20 Imp.gal)
UBD361E0.book Page 9 Monday, January 25, 2016 10:53 AM

4-10
4
immediately. If gasoline spills on your skin,
wash with soap and water. If gasoline spills on
your clothing, change your clothes.
NOTICEECB00071Use 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. Your Yamaha engine has been designed to use
regular unleaded gasoline with a research octane
number of 91 or higher (95 or higher for Europe). If
knocking (or pinging) occurs, use a gasoline of a
different brand. Use of unleaded fuel will extend
spark plug life and reduce maintenance costs.EBU18821Fuel cockThe fuel cock supplies fuel from the tank to the
carburetor 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 posi-
tion when the engine is not running.
1. Arrow mark positioned over “OFF”
1
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4-11
4ON
With the fuel cock lever in this position, fuel flows
to the carburetor. Turn the fuel cock lever to this
position when starting the engine and riding. RES
This indicates reserve. With the fuel cock lever in
this position, the fuel reserve is made available.
Turn the fuel cock lever to this position if you run
out of fuel while riding. When this occurs, refuel as
soon as possible and be sure to turn the fuel cock
lever back to “ON”!
EBU18851Starter (choke) “ ”Starting a cold engine requires a richer air-fuel
mixture, which is supplied by the starter (choke).
Move the starter (choke) in direction (a) to turn on
the starter (choke).
1. Arrow mark positioned over “ON”
1
1. Arrow mark positioned over “RES”
1
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