2018 YAMAHA YFM90 ECO mode

7-5
7Pre-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 5-1. 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 4-3.)
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 limiter
adjusting screw back in again and adjust it out inUBD362E0.book Page 5 Tuesday, January 31, 2017 5:10 PM

8-31
8
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 4-12.)
2. Unhook the battery band.
UBD362E0.book Page 31 Tuesday, January 31, 2017 5:10 PM

10-2
10
Type:SAE 5W-30, 10W-30, 10W-40, 15W-40, 20W-40 or 20W-
50
Recommended engine oil grade: API service SG type or higher, JASO standard MA
Engine oil quantity: Periodic 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
Fuel:Recommended fuel:Regular unleaded gasoline only
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)Carburetor:Type × quantity:
H66D x 1Spark plug (s):Manufacturer/model: NGK/CR6HSA
Spark plug gap:
0.6–0.7 mm (0.024–0.028 in)Clutch:Clutch type:Dry, centrifugal automaticTransmission:Secondary reduction system:Chain drive
Secondary reduction ratio: 35/14 (2.500)
Transmission type:
V-belt automatic
Operation: Centrifugal automatic typeChassis:Frame type:
Steel tube frame
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
UBD362E0.book Page 2 Tuesday, January 31, 2017 5:10 PM

10-3
10
Caster angle:3.40 °
Trail: 19.8 mm (0.78 in)Front tire:Type:Tubeless
Size: AT18 x 7-8
Manufacturer/model:
DURO/DI2017Rear tire:Type:Tubeless
Size:
AT18 x 9-8
Manufacturer/model: DURO/DI2016Loading:Maximum loading limit:
82.0 kg (181 lb)
(Total weight of rider, cargo, accessories, and tongue)Tire air pressure (measured on cold tires):Recommended:Front:
24.0 kPa (0.240 kgf/cm², 3.5 psi)
Rear: 24.0 kPa (0.240 kgf/cm², 3.5 psi)
Minimum: Front: 20.7 kPa (0.207 kgf/cm², 3.0 psi) Rear:
20.7 kPa (0.207 kgf/cm², 3.0 psi)
Front wheel:Wheel type:
Panel wheel
Rim size: 8 x 5.5ATRear wheel:Wheel type:
Panel wheel
Rim size: 8 x 5.5ATFront brake:Type:
Mechanical leading, trailing drum brake
Operation: Right hand operationRear brake:Type:
Mechanical leading, trailing drum brake
Operation: Left hand operationFront suspension:Type:
Swing axle
Spring/shock absorber type: Coil spring/oil damper
Wheel travel: 126 mm (5.0 in)
UBD362E0.book Page 3 Tuesday, January 31, 2017 5:10 PM

11-1
11
EBU26001
CONSUMER INFORMATION
EBU28202Identification numbersRecord the vehicle identification number and
model label information in the spaces provided
below for assistance when ordering spare parts
from a Yamaha dealer or for reference in case the
ATV is stolen.
VEHICLE IDENTIFICATION NUMBER:
MODEL LABEL INFORMATION:EBU26031Vehicle identification number
The vehicle identification number is stamped into
the frame.
TIPThe vehicle identification number is used to iden-
tify your ATV. EBU26051Model label
The model label is affixed at the location in the il-
lustration. Record the information on this label in
the space provided. This information will be need-
ed when ordering spare parts from a Yamaha
dealer.1. Vehicle identification number
1
UBD362E0.book Page 1 Tuesday, January 31, 2017 5:10 PM