weight YAMAHA YFM90R 2021 Owners Manual

3-2
3
Never operate at speeds too fast for your skills
or the riding conditions. Always go at a speed
that is proper for the terrain, visibility, operating
conditions, and your experience.
 Never attempt wheelies, jumps, or other stunts.
 Always inspect your ATV each time you use it to
make sure it is in safe operating condition. Al-
ways follow the inspection and maintenance
procedures and schedules described in this
manual.
 Always keep both hands on the handlebars and
both feet on the footboards of the ATV during
operation.
 Always go slowly and be extra careful when op-
erating on unfamiliar terrain. Always be alert to
changing terrain conditions when operating the
ATV.
 Never operate on excessively rough, slippery or
loose terrain until you have learned and prac-
ticed the skills necessary to control the ATV on
such terrain. Always be especially cautious on
these kinds of terrain.
 Always follow proper procedures for turning as
described in this manual. Practice turning at low
speeds before attempting to turn at faster
speeds and never turn at excessive speeds. 
Never operate the ATV on hills too steep for the
ATV or for your abilities. Practice on smaller hills
before attempting larger hills.
 Always follow proper procedures for climbing
hills as described in this manual. Check the ter-
rain carefully before you start up any hill. Never
climb hills with excessively slippery or loose
surfaces. Shift your weight forward. Never open
the throttle suddenly or make sudden gear
changes. Never go over the top of a hill at high
speed.
 Always follow proper procedures for going
down hills and for braking on hills as described
in this manual. Check the terrain carefully before
you start down any hill. Shift your weight back-
ward. Never go down a hill at high speed. Avoid
going down a hill at an angle that would cause
the vehicle to lean sharply to one side. Go
straight down the hill where possible.
 Always follow proper procedures for crossing
the side of a hill as described in this manual.
Avoid hills with excessively slippery or loose
surfaces. Shift your weight to the uphill side of
the ATV. Never attempt to turn the ATV around
on any hill until you have mastered the turning
UBD365E0.book Page 2 Monday, January 27, 2020 9:05 AM

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3
ungrounded or broken wiring. Visually check
for broken wiring and leaking fuel. Leaking
fuel can be confirmed by the odor of gasoline.
4. Once immediate safety hazards are con- firmed not to exist, you may remove your hel-
met to more closely inspect your vehicle.
Check for external signs of wear, broken
parts, fluid leaks, cracks in the frame, sus-
pension damage, wheel damage, and so on.
Fuel, oil, and coolant usually give off a notice-
able odor.
5. If your vehicle will not restart or if it is unsafe to ride, then turn off all vehicle systems (en-
gine stop switch, main switch, and fuel cock),
and then signal or go for help.
Aftermarket Parts, Accessories, and Modifica-
tions
While you may find aftermarket products similar in
design and quality to genuine Yamaha accesso-
ries, recognize that some aftermarket accessories
or modifications are not suitable because of po-
tential safety hazards to you or others. Installing
aftermarket products or having other modifica-
tions performed to your vehicle that change any of
the vehicle’s design or operation characteristics
can put you and others at greater risk of serious injury or death. You are responsible for injuries re-
lated to changes in the vehicle. Keep the following
guidelines in mind, as well as those found in the
Loading section (page 7-7) when mounting acces-
sories.

Never install accessories that would impair the
performance of your ATV. Carefully inspect the
accessory before using it to make sure that it
does not in any way reduce ground clearance,
limit suspension travel, steering travel or control
operation.
 Accessories fitted to the ATV can create insta-
bility due to improper weight distribution.
 Bulky or large accessories may seriously affect
the stability of the ATV.
 Certain accessories can displace the operator
from his or her normal riding position. This im-
proper position limits the freedom of movement
of the operator and may limit control ability,
therefore, such accessories are not recom-
mended.
 Use caution when adding electrical accesso-
ries. If electrical accessories exceed the capac-
ity of the ATV’s electrical system, an electric
failure could result, which could cause a dan-
UBD365E0.book Page 5 Monday, January 27, 2020 9:05 AM

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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
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)
UBD365E0.book Page 15 Monday, January 27, 2020 9:05 AM

7-7
7
Do not mount an accessory where it could inter-
fere with your ability to control the ATV. Exam-
ples include (but are not limited to) a heavy or
bulky object attached to the handlebars which
could make steering difficult, an accessory that
limits your ability to move around on the seat, or
one that limits your view.
 Use extra caution when riding an ATV with ac-
cessories. The ATV may handle differently than
it does without accessories.
EBU33880Loading
WARNING
EWB00821Never exceed the stated load capacity for this
ATV. Overloading this ATV or carrying or tow-
ing cargo improperly could cause changes in
ATV handling which could lead to an accident.
Cargo should be properly distributed and se-
curely attached. Reduce speed when carrying
cargo or pulling a trailer. Allow greater dis-
tance for braking. As originally equipped, this ATV is not designed to
carry cargo or tow a trailer. If you choose to add
accessories so that you can carry cargo or tow a trailer, you must use common sense and good
judgment as the stability and handling of an ATV
can be changed. When adding accessories, keep
the following points in mind:

Never exceed the weight limits shown. An over-
loaded ATV can be unstable.
 If you are carrying cargo and towing a trailer, in-
clude the tongue weight in the maximum ATV
load limit.
 Load cargo on the carriers as close to the center
of the ATV as possible. Put cargo at the rear of
the front carrier, at the front of the rear carrier,
and center it.
 Tie down cargo securely to the carriers. Make
sure cargo in the trailer cannot move around. A
shifting load can cause an accident.
 Make sure the load does not interfere with con-
trols or your ability to see where you are going.
 Ride more slowly than you would without a
load. The more weight you carry, the slower you
should go. MAXIMUM LOADING LIMIT
ATV loading limit (total weight of rider, car-
go, accessories, and tongue weight):82.0 kg (181 lb)UBD365E0.book Page 7 Monday, January 27, 2020 9:05 AM

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7

Allow more braking distance. A heavier ATV
takes longer to stop.
 Avoid making sharp turns unless at very slow
speeds.
 Avoid hills and rough terrain. Choose terrain
carefully. Added weight affects the stability and
handling of the ATV.
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8-6
8
adjusting screw back in again and adjust it out in
stages as you did before. For engine speed limiter
plate removal instructions, see page 5-4.
Loading and accessories
WARNING
EWB00973Improper loading or towing can increase the
risk of loss of control, an overturn, or other ac-
cident. To reduce the risk of an accident:

Do not exceed the maximum loading limits
for the vehicle (see “MAXIMUM LOADING
LIMIT” below or vehicle labeling). 
Make sure the load does not interfere with
your control or ability to see where you are
going.
 Reduce speed and allow more room to stop.
A heavier vehicle takes longer to stop.
 Avoid hills and rough terrain. Choose terrain
carefully. Use extreme caution when towing
or carrying a load on inclines.
 Turn gradually and go slowly.
As originally equipped, this ATV is not designed to
carry cargo or tow a trailer. If you choose to add
accessories to carry cargo, you must use com-
mon sense and good judgment.
Use extra caution when riding the ATV with addi-
tional loads, such as accessories or cargo. The
ATV’s handling may be adversely affected. Re-
duce your speed when adding additional loads.
1. Adjusting screw
1
MAXIMUM LOADING LIMIq
ATV loading limit (total weight of cargo, rid-
er, accessories, and tongue weight):82.0 kg (181 lb)
UBD365E0.book Page 6 Monday, January 27, 2020 9:05 AM

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abruptly, the vehicle may lurch forward or the front
wheels may lift off the ground, resulting in a loss of
directional control. Avoid higher speeds until you
are thoroughly familiar with the operation of your
ATV.
When slowing down or stopping, release the
throttle and apply the brakes smoothly and evenly.
Improper use of the brakes can cause the tires to
lose traction, reducing control and increasing the
possibility of an accident.
TURNING YOUR ATV
WARNING
EWB01772Always follow proper procedures for turning as
described in this Owner’s Manual. Practice
turning at low speeds before attempting to turn
at faster speeds. Do not turn at speeds too fast
for your skills or the conditions. ATV could go
out of control, causing a collision or overturn. To achieve maximum traction on unpaved surfac-
es, the two rear wheels turn together at the same
speed. Therefore, unless the wheel on the inside
of the turn is allowed to slip or lose some traction,
the ATV will resist turning. A special turning tech- nique must be used to allow the ATV to make
turns quickly and easily. It is essential that this skill
be learned first at low speed.
As you approach a curve, slow down and begin to
turn the handlebars in the desired direction. As
you do so, put your weight on the footboard to the
outside of the turn (opposite your desired direc-
tion) and lean your upper body into the turn. Use
the throttle to maintain an even speed through the
turn. This maneuver will let the wheel on the inside
of the turn slip slightly, allowing the ATV to make
the turn properly.UBD365E0.book Page 12 Monday, January 27, 2020 9:05 AM

8-13
8This procedure should be practiced at slow speed
many times in a large unpaved area with no obsta-
cles. If an incorrect technique is used, your ATV
may continue to go straight. If the ATV doesn’t
turn, come to a stop and then practice the proce-
dure again. If the riding surface is slippery or
loose, it may help to position more of your weight
over the front wheels by moving forward on the
seat. Once you have learned this technique, you should
be able to perform it at higher speeds or in tighter
curves.
Improper riding procedures such as abrupt throt-
tle changes, excessive braking, incorrect body
movements, or too much speed for the sharpness
of the turn may cause the ATV to tip. If the ATV be-
gins to tip over to the outside while negotiating a
turn, lean more to the inside. It may also be nec-
essary to gradually let off on the throttle and steer
to the outside of the turn to avoid tipping over.
Remember: Avoid higher speeds until you are
thoroughly familiar with the operation of your ATV.
CLIMBING UPHILL
WARNING
EWB01672Climbing hills improperly can cause overturns
or loss of control. Use proper riding techniques
described in this Owner’s Manual.

Never operate the ATV on hills too steep for
the ATV or for your abilities. The ATV can
overturn more easily on extremely steep hills
than on level surfaces or small hills.
 Always check the terrain carefully before you
start up any hill. Never climb hills with exces-
sively slippery or loose surfaces.
1. Lean towards inside of turn.
2. Support your weight on the outer footboard.
1
2
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8

Shift your weight forward.
 Never open the throttle suddenly. The ATV
could flip over backwards.
 Never go over the top of any hill at high
speed. An obstacle, a sharp drop, or another
vehicle or person could be on the other side
of the hill.
 Never attempt to turn the ATV around on any
hill until you have mastered the turning tech-
nique as described in the Owner’s Manual on
level ground. Be very careful when turning
on any hill.
 Avoid crossing the side of a steep hill if pos-
sible. When crossing the side of a hill, shift
your weight to the uphill side of the ATV.

OK
UBD365E0.book Page 14 Monday, January 27, 2020 9:05 AM