ECO mode YAMAHA YFM90R 2021 Owners Manual

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EBU38860
VEHICLE IDENTIFICATION
EBU28205Identification numbersRecord the vehicle identification number and
model label information in the spaces provided
below.
VEHICLE IDENTIFICATION NUMBER:
MODEL LABEL INFORMATION:EBU26032Vehicle identification number
The vehicle identification number is stamped into
the frame. This 17-digit number is used to identify
your individual ATV.
EBU26053Model label
The model label is affixed at the location shown.1. Vehicle identification number
1
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5
TIPConfirm the gasoline pump nozzle has the same
fuel identification mark.
About the recommended fuel
This model’s engine has been designed to use
regular unleaded gasoline. The research octane
number should be 95 or higher. If knocking or
pinging occurs, try a gasoline of a different brand
or higher octane.TIPGasoline containing ethanol can be used if the
ethanol content does not exceed 10% (E10). Gas-
oline containing methanol is not recommended
because it can cause damage to the fuel system
or vehicle performance problems. 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. 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.
Recommended fuel:
Regular unleaded gasoline (Gasohol [E10]
acceptable)
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)
1. EN228 fuel identification mark
1
E5
E10
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8Pre-operation checks
Always inspect your ATV before use to make sure
that it is safe operating condition. Perform the pre-
operation checks listed on page 6-1. Follow the
maintenance schedules and procedures as de-
scribed in the “Periodic Maintenance and Adjust-
ment” section of this manual.
WARNING! Failure
to inspect the ATV before riding it or failure to
maintain it properly increases the possibility of
an accident and equipment damage.
[EWB01433]
Speed limiter
For beginning riders, riders less experienced with
this model, or whenever limited speed is desir-
able, the throttle lever housing is equipped with a vehicle speed limiter. The speed limiter keeps the
throttle from fully opening, even when the throttle
lever is pushed to the maximum. Turning in the
adjusting screw limits the maximum engine power
available and decreases the maximum speed of
the ATV. Turning in the adjusting screw decreases
top speed, and turning it out increases top speed.
(See page 5-3.)
This model also has an engine speed limiter plate
to limit the amount of engine power available.
Yamaha recommends that all beginning riders start off with the engine speed limiter plate in-
stalled and the vehicle speed limiter adjusting
screw turned in to limit the amount of speed avail-
able while they learn. The vehicle speed limiter
may be gradually adjusted to increase maximum
speed as the beginner becomes more familiar with
operating the ATV. Parents should decide when to
adjust the ATV for more power as their young-
ster’s riding skills improve. Once the ATV rider can
operate with skill at the top speed permitted by
adjusting the vehicle speed limiter alone, the en-
gine speed limiter plate can be removed. Since re-
moval of this plate will result in a significant
increase in power, turn the vehicle speed limiterUBD365E0.book Page 5 Monday, January 27, 2020 9:05 AM

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TIPFor parts equipped with a grease nipple, use a
grease gun. EBU34022BatteryThis model is equipped with a 12-volt VRLA
(valve-regulated lead-acid) battery. There is no
need to check the electrolyte or to add distilled
water. However, the battery lead connections
need to be checked and tightened, and the bat-
tery terminals cleaned if corroded. If the battery
seems to have discharged, recharge it as soon as
possible.TIPWear gloves and eye protection in a ventilated
area away from sparks and open flames. Wash
hands after handling.
 It is recommended to have the battery serviced
by a Yamaha dealer.
WARNING
EWB02161Battery electrolyte is poisonous and danger-
ous, as it contains sulfuric acid, which can cau-
se severe burns. Avoid contact with skin, eyes
or clothing. Always shield your eyes when
working near batteries.
Antidote:
EXTERNAL: Flush with water.
INTERNAL: Drink large quantities of water or
milk. Follow with milk of magnesia, beaten egg
or vegetable oil. Call a physician immediately.
EYES: Flush with water for 15 minutes and get
prompt medical attention.
Batteries produce explosive gases. Keep
sparks, flame, cigarettes or other sources of
ignition away. Ventilate when charging or using
in an enclosed space.
KEEP OUT OF REACH OF CHILDREN. To remove the battery
1. Remove the seat. (See page 5-13.)
2. Unhook the battery band.
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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
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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