YAMAHA YFM90R 2021 Owners Manual

11-2
11
Engine oil:Recommended brand:
SAE viscosity grades:5W-30, 10W-30, 10W-40, 15W-40, 20W-40, 20W-50
Recommended engine oil grade: API service SG type or higher, JASO standard MA
Quantity: Oil change:0.80 L (0.85 US qt, 0.70 Imp.qt)Transmission oil:Type:SAE 80W-90
Quantity: 0.35 L (0.37 US qt, 0.31 Imp.qt)
Air filter:Air filter element:Wet element
Air filter oil grade:
Foam air-filter oilFuel:Recommended fuel:Regular unleaded gasoline (Gasohol [E10] acceptable)
Minimum research octane:
91
Fuel tank capacity: 6.6 L (1.7 US gal, 1.5 Imp.gal)
Fuel reserve amount: 0.9 L (0.24 US gal, 0.20 Imp.gal)Carburetor:Type × quantity:
H66D16 × 1Spark plug (s):Manufacturer/model:
NGK/CR6HSA
Spark plug gap: 0.6–0.7 mm (0.024–0.028 in)Drivetrain:Primary reduction ratio:
1.000
Secondary reduction ratio: 2.500 (35/14)
Final drive: Chain
Clutch type:
Dry, centrifugal, shoe
0 10 30 50 70 90 110 130 ˚F
–20 –10 0 10 20 30 40 50 ˚CSAE 5W-30
SAE 10W-30
SAE 10W-40
SAE 15W-40
SAE 20W-40SAE 20W-50
UBD365E0.book Page 2 Monday, January 27, 2020 9:05 AM

11-3
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Transmission type:CVT automatic with reverse
Gear ratio: Transmission ratio: 2.570–0.851 : 1
Forward gear: 8.292 (49/15 x 33/13)
Reverse gear:
25.395 (49/15 x 49/16 x 33/13)Front tire:Size:AT18 x 7-8
Manufacturer/model:
DURO/DI2017Rear tire:Size:AT18 x 9-8
Manufacturer/model:
DURO/DI2016Tire air pressure (measured on cold tires):Vehicle load:0.0–82.0 kg (0–181 lb)
Recommended:
Front: 25.0 kPa (0.250 kgf/cm², 3.6 psi)
Rear:
25.0 kPa (0.250 kgf/cm², 3.6 psi)
Minimum: Front:
22.0 kPa (0.220 kgf/cm², 3.2 psi)
Rear: 22.0 kPa (0.220 kgf/cm², 3.2 psi)
Front wheel:Rim size:8 x 5.5ATRear wheel:Rim size:8 x 5.5ATFront brake:Type:
Mechanical leading, trailing drum brakeRear brake:Type:Mechanical leading, trailing drum brakeFront suspension:Type:Swing axle
Spring: Coil spring
Shock absorber:
Gas-hydraulic damper
Wheel travel: 126 mm (5.0 in)Rear suspension:Type:
Swingarm
Spring: Coil spring
Shock absorber: Gas-hydraulic damper
Wheel travel:
145 mm (5.7 in)
UBD365E0.book Page 3 Monday, January 27, 2020 9:05 AM

11-4
11
Electrical system:System voltage:12 V
Ignition system:
CDI
Charging system: AC magnetoBattery:Model:
GTX5L-BS
Voltage, capacity: 12 V, 4.0 AhLights:Neutral indicator light:
3.5 W
Reverse indicator light: 3.5 WFuses:Main fuse:
7.5 AEBU30403Noise and vibration levels statement (for Eu-
rope)
The figures quoted are emission levels and are not
necessarily safe working levels. Whilst there is a
correlation between the emission and exposure
levels, this cannot be used reliably to determine
whether or not further precautions are required. Factors that influence the actual level of exposure
of work-force include the characteristics of the
work room, the other sources of noise, etc. i.e. the
number of machines and other adjacent process-
es, and the length of time for which an operator is
exposed to the noise. Also the permissible expo-
sure level can vary from country. This information,
however, will enable the user of the machine to
make a better evaluation of the hazard and risk.
EBU38670CO2 emissions levels statement (for Europe)
This CO2 measurement results from testing over a
fixed test cycle under laboratory conditions a(n)
(parent) engine representative of the engine type
(engine family) and shall not imply or express any
guarantee of the performance of a particular en-
gine.
UBD365E0.book Page 4 Monday, January 27, 2020 9:05 AM

12-1
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INDEX
AAccessories and loading ................................................ 7-6
Air filter element, cleaning ............................................ 9-15BBattery .......................................................................... 9-31
Brake lever free play, adjusting the front ..................... 9-23
Brake lever free play (rear), adjusting ........................... 9-24
Brake lever, front ............................................................ 5-5
Brake lever, rear ............................................................. 5-5
Brake levers, checking and lubricating ........................ 9-28
Brakes .......................................................................... 9-21
Brakes, front and rear .................................................... 6-3CCables, checking and lubricating ................................. 9-28
Carburetor, adjusting ...................................................9-19
Chassis fasteners ........................................................... 6-6
Cleaning ....................................................................... 10-1DDrive chain ..................................................................... 6-3
Drive chain, lubricating ................................................ 9-27
Drive chain slack .......................................................... 9-25
Drive select lever ............................................................ 5-6
Drive select lever and driving in reverse ........................ 7-3EEngine break-in .............................................................. 7-4
Engine, cold start ........................................................... 7-1
Engine idling speed ...................................................... 9-19
Engine oil .............................................................. 6-3, 9-10
Engine, starting a warm ................................................. 7-3Engine stop switch ......................................................... 5-2
FFront and rear brake shoes, checking ......................... 9-21
Front arm pivots, lubricating ........................................ 9-29
Front knuckle pivots, lubricating .................................. 9-30
Fuel ........................................................................ 5-9, 6-3
Fuel cock ...................................................................... 5-10
Fuel tank cap ................................................................. 5-8
Fuse, replacing ............................................................. 9-34HHandlebar switches ....................................................... 5-2IIdentification numbers ................................................... 1-1
Indicator lights ............................................................... 5-1
Instruments and switches .............................................. 6-6KKickstarter ...................................................................... 5-7LLabel locations ............................................................... 2-1MMain switch .................................................................... 5-1
Maintenance and lubrication chart ................................ 9-5
Maintenance chart, emission control system ................ 9-3
Model label .................................................................... 1-1NNeutral indicator light ..................................................... 5-1OOwner’s Manual and tool kit .......................................... 9-2
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PParking ........................................................................... 7-5
Parking brake ................................................................. 5-5
Parking on a slope ......................................................... 7-5
Part locations ................................................................. 4-1RReverse indicator light ................................................... 5-1
Riding your ATV ............................................................. 8-1SSafety information .......................................................... 3-1
Seat .............................................................................. 5-13
Shock absorber, rear ................................................... 5-15
Shock absorbers, front ................................................ 5-13
Spark arrester, cleaning ............................................... 9-18
Spark plug, checking ..................................................... 9-9
Specifications .............................................................. 11-1
Speed limiter .................................................................. 5-3
Starter (choke) ............................................................. 5-12
Start switch .................................................................... 5-2
Steering shaft, lubricating ............................................ 9-30
Storage ........................................................................ 10-2TThrottle lever ...........................................................5-2, 6-3
Throttle lever free play, adjusting ................................ 9-20
Tires ............................................................................... 6-3
Transmission .................................................................. 6-3
Transmission oil ........................................................... 9-14
Troubleshooting ........................................................... 9-36
Troubleshooting chart .................................................. 9-37VValve clearance ............................................................ 9-21Vehicle identification number ........................................ 1-1
WWheel hub bearings, checking .................................... 9-29
Wheel, installing ........................................................... 9-35
Wheel, removing .......................................................... 9-34YYamalube ..................................................................... 9-13
UBD365E0.book Page 2 Monday, January 27, 2020 9:05 AM

EBU33962
WARNING
ALWAYS
:
• use proper riding techniques to avoid
vehicle overturns on hills and rough
terrain and in turns.
• avoid paved surfaces—pavement may
seriously affect handling and control.
Improper ATV use can result in SEVERE INJURY or DEATH.
NEVER USE
WITH DRUGS
OR ALCOHOL
ALWAYS USE
AN APPROVED HELMET AND
PROTECTIVE GEAR NEVER USE
ON PAVED ROADS NEVER CARRY
PASSENGERS
NEVER
operate:
• without proper training or instruction.
• at speeds too fast for your skills or the
conditions.
• on public roads—a collision can occur with
another vehicle.
• with a passenger—passengers affect
balance and steering and increase risk
of losing control.
LOCATE AND READ OWNER’S MANUAL. FOLLOW ALL INSTRUCTIONS AND WARNINGS.
PRINTED IN TAIWAk 2020.02 (EF
UBD365E0.book Page 1 Monday, January 27, 2020 9:05 AM