brake YAMAHA YFM90R 2020 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 ......................................... 4-5
Rear brake lever .......................................... 4-5
Parking brake .............................................. 4-5
Drive select lever ......................................... 4-6
Kickstarter ................................................... 4-7
Fuel tank cap .............................................. 4-8
Fuel ............................................................. 4-9 Fuel cock .................................................. 4-10
Starter (choke) ......................................... 4-12
Seat .......................................................... 4-13
Front shock absorbers ............................. 4-13
Rear shock absorber ................................ 4-15
PRE-OPERATION CHECKS .......................... 5-1 Fuel ............................................................. 5-3
Engine oil .................................................... 5-3
Transmission .............................................. 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 ...................................... 6-3
Engine break-in........................................... 6-4
Parking........................................................ 6-5UBD364E0.book Page 1 Monday, January 28, 2019 9:30 AM

Parking on a slope ...................................... 6-5
Accessories and loading ............................. 6-6
RIDING YOUR ATV ........................................ 7-1 GETTING TO KNOW YOUR ATV ................ 7-2
RIDE WITH CARE AND GOOD JUDGMENT .............................................. 7-2
BE CAREFUL WHERE YOU RIDE ............... 7-9
TURNING YOUR ATV................................ 7-12
CLIMBING UPHILL ................................... 7-13
RIDING DOWNHILL .................................. 7-16
CROSSING A SLOPE................................ 7-17
CROSSING THROUGH SHALLOW WATER .................................................... 7-18
RIDING OVER ROUGH TERRAIN ............. 7-20
SLIDING AND SKIDDING .......................... 7-20
WHAT TO DO IF... ..................................... 7-21
WHAT TO DO... ......................................... 7-22
PERIODIC MAINTENANCE AND
ADJUSTMENT................................................ 8-1 Owner’s Manual and tool kit ....................... 8-2
Periodic maintenance chart: Emission control system .......................................... 8-3
Periodic maintenance chart: General maintenance and lubrication..................... 8-5
Checking the spark plug ............................. 8-9 Engine oil .................................................. 8-10
Why Yamalube.......................................... 8-13
Transmission oil ........................................ 8-14
Cleaning the air filter element ................... 8-15
Cleaning the spark arrester ...................... 8-18
Adjusting the carburetor ........................... 8-19
Adjusting the engine idling speed ............ 8-19
Adjusting the throttle lever free play ......... 8-20
Valve clearance......................................... 8-21
Brakes....................................................... 8-21
Checking the front and rear brake
shoes ...................................................... 8-21
Adjusting the front brake lever free play... 8-23
Adjusting the rear brake lever free play .... 8-24
Drive chain slack....................................... 8-25
Lubricating the drive chain ....................... 8-27
Checking and lubricating the cables ........ 8-28
Checking and lubricating the front and rear brake levers ..................................... 8-29
Checking the wheel hub bearings ............ 8-29
Lubricating the front arm pivots ............... 8-30
Lubricating the front knuckle pivots ......... 8-30
Lubricating the steering shaft ................... 8-31
Battery ...................................................... 8-31
Replacing the fuse .................................... 8-34
Removing a wheel .................................... 8-35
Installing a wheel ...................................... 8-35
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2-3
2
technique described in this manual on level
ground. Avoid crossing the side of a steep hill if
possible.
 Always use proper procedures if you stall or roll
backwards when climbing a hill. To avoid stall-
ing, use the proper gear and maintain a steady
speed when climbing a hill. If you stall or roll
backwards, follow the special procedure for
braking described in this manual. Dismount on
the uphill side or to a side if pointed straight up-
hill. Turn the ATV around and remount, following
the procedure described in this manual.
 Always check for obstacles before operating in
a new area.
 Never attempt to operate over large obstacles,
such as large rocks or fallen trees. Always follow
proper procedures when operating over obsta-
cles as described in this manual.
 Always be careful when skidding or sliding.
Learn to safely control skidding or sliding by
practicing at low speeds and on level, smooth
terrain. On extremely slippery surfaces, such as
ice, go slowly and be very cautious in order to
reduce the chance of skidding or sliding out of
control. 
Never operate an ATV in fast flowing water or in
water deeper than that recommended in this
manual. Remember that wet brakes may have
reduced stopping ability. Test your brakes after
leaving water. If necessary, apply them several
times to let friction dry out the linings.
 Always be sure there are no obstacles or people
behind you when you operate in reverse. When
it is safe to proceed in reverse, go slowly.
 Always use the size and type of tires specified in
this manual.
 Always maintain proper tire pressure as de-
scribed in this manual.
 Never exceed the stated load capacity for an
ATV. Cargo should be properly distributed and
securely attached. Reduce speed and follow in-
structions in this manual for carrying cargo or
pulling a trailer. Allow greater distance for brak-
ing.
 Do not operate your ATV during darkness un-
less it is equipped with a properly functioning
headlight. Off-road riding is inherently danger-
ous and additionally, off-road trails do not have
streetlights to guide you.
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3-2
3
EBU17715Controls and instruments1. Rear brake lever
2. Handlebar switches
3. Parking brake lock plate
4. Starter (choke) lever
5. Main switch
6. Throttle lever
7. Front brake lever
8. Drive select lever
1
2
3
5
6
7
4
8
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4-5
4
EBU18393Front brake leverThe front brake lever is located on the right han-
dlebar. To apply the front brake, pull the brake le-
ver toward the handlebar grip.
EBU18403Rear brake leverThe rear brake lever is located on the left handle-
bar. To apply the rear brake, pull the brake lever
toward the handlebar grip.EBU18462Parking brakeUse the parking brake before starting the engine
or after parking the ATV, especially on a slope. Ap-
ply 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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4-6
4
WARNING
EWB00221Always set the parking brake before starting
the engine. The ATV could start moving un-
expectedly if the parking brake is not ap-
plied. This could cause loss of control or a
collision.
 Always be sure you have released the park-
ing brake before you begin to ride. The brake
could overheat if you ride the ATV without re-
leasing the parking brake. You could lose braking performance which could cause an
accident. You could also wear out the brakes
prematurely.
EBU18583Drive select leverThe drive select lever is used to shift the transmis-
sion into the forward, neutral and reverse posi-
tions. See page 6-3 for drive select lever
operation.
1. Parking brake lock plate
1
1. Drive select lever
1
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5-1
5
EBU19203
PRE-OPERATION CHECKS
EBU19226Inspect your vehicle each time you use it to make sure the vehicle is in safe operating condition. Always
follow the inspection and maintenance procedures and schedules described in the Owner’s Manual.
WARNING
EWB00482Failure to inspect or maintain the vehicle properly increases the possibility of an accident or equip-
ment damage. Do not operate the vehicle if you find any problem. If a problem cannot be corrected
by the procedures provided in this manual, have the vehicle inspected by a Yamaha dealer. Before using this vehicle, check the following points:
ITEMROUTINE PAGE
Fuel • Check fuel level in fuel tank,
and add recommended fuel if neces-
sary.
• Check fuel line for leakage. Correct if necessary. 4-9, 5-3
Engine oil • Check oil level in engine, and add recommended oil to specified
level if necessary.
• Check ATV for oil leakage. Correct if necessary. 5-3, 8-10
Transmission • Check transmission case for leakage. 5-3, 8-14
Front brake • Check operation, and correct if necessary.
• Lubricate cable if necessary.
• Check lever free play, and adjust if necessary. 5-3, 8-21, 8-23
Rear brake • Check operation, and correct if necessary.
• Lubricate cable if necessary.
• Check lever free play, and adjust if necessary. 5-3, 8-21, 8-24
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5-2
5
Throttle lever• Make sure that operation is smooth. Lubricate cable and lever
housing if necessary.
• Check lever free play, and adjust if necessary. 5-3, 8-20
Control cables • Make sure that operation is smooth. Lubricate if necessary. 8-28
Drive chain • Check chain slack, and adjust if necessary.
• Check chain condition. Lubricate if necessary. 5-3, 8-25, 8-27
Wheels and tires • Check wheel condition, and replace if damaged.
• Check tire condition and tread depth. Replace if necessary.
• Check air pressure. Correct if necessary. 5-3
Brake levers • Make sure that operation is smooth. Lubricate lever pivoting points
if necessary. 8-29
Chassis fasteners • Make sure that all nuts, bolts and screws are properly tightened. 5-6
Instruments and switches • Check operation, and correct if necessary. 5-6
ITEM ROUTINE PAGE
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5-3
5
EBU38000FuelMake sure there is sufficient gasoline in the tank
before starting off. Refuel if necessary. (See page
4-9.)EBU19561Engine oilMake sure that the engine oil is at the specified
level. Add oil as necessary. (See page 8-10.)EBU38541TransmissionMake sure there is no oil leaking from the trans-
mission case.EBU19653Front and rear brakesBrake levers
Check for correct free play in the brake levers. If
the free play is incorrect, adjust it. (See pages
8-23 and 8-24.)
 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 brake shoes for wear. (See page 8-21.)
EBU19762Throttle leverCheck the operation of the throttle lever. It must
open smoothly and spring back to the idle position
when released. Have a Yamaha dealer correct if
necessary.EBU19771Drive chainCheck the condition of the drive chain and check
the drive chain slack. Lubricate and adjust the
drive chain as necessary. (See page 8-25.)EBU19799TiresCheck tire pressure regularly to make sure it is at
the recommended specifications. Also check for
wear and damage.
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6-1
6
EBU19882
OPERATION
EBU19902Read the Owner’s Manual carefully before riding
the ATV. If there is a control or function you do not
understand, ask your Yamaha dealer.
WARNING
EWB00632Read the Owner’s Manual carefully to become
familiar with all controls in order to help pre-
vent any loss of control, which could cause an
accident or injury. EBU33822Starting a cold engineNOTICEECB00151See the “Engine break-in” section on page 6-4
prior to operating the engine for the first time. 1. Set the parking brake. (The engine can bestarted only when the rear brake lever is ap-
plied.)
2. Turn the fuel cock to “ON”. 3. Turn the key to “ON” and set the engine stop
switch to “ ”.
4. Shift the drive select lever into the neutral po- sition. (The neutral indicator light should
come on.)
5. Position the starter (choke) lever according to the ambient temperature.
Position (1):
Cold engine start with ambient temperature
below 5 °C (40 °F).
Position (2):
Cold engine start with ambient temperature
between 0 °C (30 °F) and 30 °C (90 °F).
Position (3):
Cold engine start with ambient temperature
above 25 °C (80 °F).
UBD364E0.book Page 1 Monday, January 28, 2019 9:30 AM