ABS YAMAHA YFM90R 2021 Owners Manual

EBU17421
TABLE OF CONTENTS
VEHICLE IDENTIFICATION ............................ 1-1Identification numbers ................................ 1-1
LOCATION OF THE WARNING AND
SPECIFICATION LABELS .............................. 2-1
SAFETY INFORMATION ................................ 3-1
DESCRIPTION................................................ 4-1 Left view ...................................................... 4-1
Right view.................................................... 4-1
Controls and instruments............................ 4-2
INSTRUMENT AND CONTROL
FUNCTIONS ................................................... 5-1 Main switch ................................................. 5-1
Indicator lights............................................. 5-1
Handlebar switches .................................... 5-2
Throttle lever ............................................... 5-2
Speed limiter ............................................... 5-3
Front brake lever ......................................... 5-5
Rear brake lever .......................................... 5-5
Parking brake .............................................. 5-5
Drive select lever ......................................... 5-6 Kickstarter .................................................. 5-7
Fuel tank cap .............................................. 5-8
Fuel ............................................................. 5-9
Fuel cock .................................................. 5-10
Starter (choke) ......................................... 5-12
Seat .......................................................... 5-13
Front shock absorbers ............................. 5-13
Rear shock absorber ................................ 5-15
PRE-OPERATION CHECKS .......................... 6-1 Fuel ............................................................. 6-3
Engine oil .................................................... 6-3
Transmission .............................................. 6-3
Front and rear brakes ................................. 6-3
Throttle lever ............................................... 6-3
Drive chain .................................................. 6-3
Tires ............................................................ 6-3
Chassis fasteners ....................................... 6-6
Instruments and switches........................... 6-6
OPERATION .................................................. 7-1 Starting a cold engine................................. 7-1
Starting a warm engine............................... 7-3UBD365E0.book Page 1 Monday, January 27, 2020 9:05 AM

4-1
4
EBU17681
DESCRIPTION
EBU17691Left view
EBU17701Right view
1. Fuel tank cap
2. Fuel cock
3. Air filter
4. Fuse
5. Battery
6. Rear shock absorber
7. Kickstarter lever cap
1 2 3 4,576
1. Spark arrester
2. Reflector
3. Tool kit
4. Front shock absorber
5. Spark plug
6. Engine oil filler cap
7. Transmission oil filler cap123 4
76 5
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5-13
5
EBU34551SeatTo remove the seat
Push down on the rear of the seat and pull the seat
lock lever upward to release the seat lock. Then
pull up at the rear of the seat to remove it.To install the seat
Insert the projection on the front of the seat into
the seat holder, and then push down on the seat
at the rear to lock it in place. Make sure that the
seat is securely fitted.
EBU18997Front shock absorbersThe spring preload can be adjusted to suit the rid-
er’s weight and the riding conditions.
1. Seat
2. Seat lock lever
1
2
1. Projection
2. Seat holder
1
2
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5-14
5
WARNING
EWB00401Always adjust the shock absorber assemblies
on the left and right side to the same setting.
Uneven adjustment can cause poor handling
and loss of stability, which could lead to an ac-
cident. NOTICEECB01091Never turn the adjusting mechanism beyond
the minimum and maximum settings. Adjust the spring preload as follows.
Turn the spring preload adjusting ring in direction
(a) to increase the spring preload and thereby
harden the suspension, and in direction (b) to de-
crease the spring preload and thereby soften the
suspension.
Align the appropriate notch in the adjusting ring
with the position indicator on the shock absorber.
TIPA special wrench can be obtained at a Yamaha
dealer to make this adjustment. 1. Spring preload adjusting ring
2. Position indicator
123 45
2
1(a)
(b)
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5-15
5
EBU19027Rear shock absorberThe spring preload can be adjusted to suit the rid-
er’s weight and the riding conditions.
NOTICEECB01091Never turn the adjusting mechanism beyond
the minimum and maximum settings. Adjust the spring preload as follows.
Turn the spring preload adjusting ring in direction
(a) to increase the spring preload and thereby
harden the suspension, and in direction (b) to de-
crease the spring preload and thereby soften the
suspension.
1. Special wrenchSpring preload setting:Minimum (soft):1
Standard: 3
Maximum (hard): 5
1
1. Spring preload adjusting ring
2. Position indicator
1 23 45
2
1
(a)
(b)
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9-6
9
5*Wheels • Check runout and for damage, and replace if nec-
essary. √ √√√
6 *Tires • Check tread depth and for damage, and replace if
necessary.
• Check air pressure and balance, and correct if necessary. √ √√√
7 *Wheel hub bearings • Check for looseness or damage, and replace if
necessary. √ √√√
8 *Front arm pivots • Lubricate with lithium-soap-based grease. √√√
9 Drive chain • Check chain slack and adjust if necessary.
• Check rear wheel alignment and correct if neces-
sary.
• Clean and lubricate. √√√√√
10 *Drive chain rollers • Check for wear and replace if necessary. √√√
11 *V- b e l t • Check for wear, cracks or other damage, and re-
place if necessary. √ √√√
12 *Chassis fasteners • Make sure that all nuts, bolts, and screws are
properly tightened. √√√√√
13 *Shock absorber as-
semblies • Check operation and correct if necessary.
• Check for oil leakage and replace if necessary.
√√√
14 *Front knuckle piv-
ots • Lubricate with lithium-soap-based grease.
√√√
NO. ITEM
CHECK OR MAINTENANCE
JOB INITIAL EVERY
Whichev- er comes first month136612
km (mi) 320
(200) 1300
(800) 2500
(1600) 2500
(1600) 5000
(3200)
hours 20 80 160 160 320
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10-1
10
EBU25861
CLEANING AND STORAGE
EBU25903CleaningFrequent, thorough cleaning of your ATV will not
only enhance its appearance but will improve its
general performance and extend the useful life of
many components.1. Before cleaning the ATV: a. Block off the end of the exhaust pipe toprevent water entry. A plastic bag and
strong rubber band may be used.
b. Make sure the spark plug and all filler caps are properly installed.
2. If the engine case is excessively greasy, apply degreaser with a paint brush. Do not apply
degreaser to the chain, sprockets or wheel
axles.
3. Rinse the dirt and degreaser off with a garden hose. Use only enough pressure to do the
job. WARNING! Wet brakes may have re-
duced stopping ability, increasing the
chance of an accident. Test the brakes af-
ter washing. Apply the brakes several
times at slow speeds to let friction dry out
the linings.
[EWB02312]
NOTICE: Excessive wa- ter pressure may cause water seepage
and deterioration of wheel bearings,
brakes, transmission seals and electrical
devices. Many expensive repair bills have
resulted from improper high-pressure de-
tergent applications such as those avail-
able in coin-operated car washers.
[ECB00712]
4. Once most of the dirt has been hosed off,
wash all surfaces with warm water and mild,
detergent-type soap. An old toothbrush or
bottle brush is handy for hard-to-reach pla-
ces.
5. Rinse the ATV off immediately with clean wa- ter and dry all surfaces with a chamois, clean
towel or soft absorbing cloth.
6. Dry the chain and lubricate it to prevent it from rusting.
7. Clean the seat with a vinyl upholstery cleaner to keep the cover pliable and glossy.
8. Automotive type wax may be applied to all painted and chrome plated surfaces. Avoid
combination cleaner-waxes. Many contain
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11-3
11
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)
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12-2
12
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