2021 YAMAHA MT-125 Owners Manual

Safety information
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
Many accidents involve inexperi-
enced operators. In fact, many op-
erators who have been involved in
accidents do not even have a cur-
rent motorcycle license.
• Make sure that you are qualified and that you only lend your mo-
torcycle to other qualified oper-
ators.
• Know your skills and limits. Staying within your limits may
help you to avoid an accident.
• We recommend that you prac- tice riding your motorcycle
where there is no traffic until you
have become thoroughly famil-
iar with the motorcycle and all of
its controls.
 Many accidents have been
caused by error of the motorcycle
operator. A typical error made by
the operator is veering wide on a
turn due to excessive speed or un-
dercornering (insufficient lean an-
gle for the speed).
• Always obey the speed limit and never travel faster than warrant-
ed by road and traffic condi-
tions. • Always signal before turning or
changing lanes. Make sure that
other motorists can see you.
 The posture of the operator and
passenger is important for proper
control.
• The operator should keep both hands on the handlebar and
both feet on the operator foot-
rests during operation to main-
tain control of the motorcycle.
• The passenger should always hold onto the operator, the seat
strap or grab bar, if equipped,
with both hands and keep both
feet on the passenger footrests.
Never carry a passenger unless
he or she can firmly place both
feet on the passenger footrests.
 Never ride under the influence of
alcohol or other drugs.
 This motorcycle is designed for
on-road use only. It is not suitable
for off-road use. Protective Apparel
The majority of fatalities from motorcy-
cle accidents are the result of head in-
juries. The use of a safety helmet is the
single most critical factor in the pre-
vention or reduction of head injuries.
 Always wear an approved helmet.
 Wear a face shield or goggles.
Wind in your unprotected eyes
could contribute to an impairment
of vision that could delay seeing a
hazard.
 The use of a jacket, heavy boots,
trousers, gloves, etc., is effective
in preventing or reducing abra-
sions or lacerations.
 Never wear loose-fitting clothes,
otherwise they could catch on the
control levers, footrests, or wheels
and cause injury or an accident.
 Always wear protective clothing
that covers your legs, ankles, and
feet. The engine or exhaust sys-
tem become very hot during or af-
ter operation and can cause
burns.
 A passenger should also observe
the above precautions.
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Safety information
1-3
1Avoi
d Car bon Monoxi de Poisonin g
All engine exhaust contains carbon
monoxide, a deadly gas. Breathing
carbon monoxide can cause head-
aches, dizziness, drowsiness, nausea,
confusion, and eventually death.
Carbon Monoxide is a colorless, odor-
less, tasteless gas which may be pres-
ent even if you do not see or smell any
engine exhaust. Deadly levels of car-
bon monoxide can collect rapidly and
you can quickly be overcome and un-
able to save yourself. Also, deadly lev-
els of carbon monoxide can linger for
hours or days in enclosed or poorly
ventilated areas. If you experience any
symptoms of carbon monoxide poi-
soning, leave the area immediately, get
fresh air, and SEEK MEDICAL TREAT-
MENT.  Do not run engine indoors. Even if
you try to ventilate engine exhaust
with fans or open windows and
doors, carbon monoxide can rap-
idly reach dangerous levels.
 Do not run engine in poorly venti-
lated or partially enclosed areas
such as barns, garages, or car-
ports. 
Do not run engine outdoors where
engine exhaust can be drawn into
a building through openings such
as windows and doors.
Loa din g
Adding accessories or cargo to your
motorcycle can adversely affect stabil-
ity and handling if the weight distribu-
tion of the motorcycle is changed. To
avoid the possibility of an accident, use
extreme caution when adding cargo or
accessories to your motorcycle. Use
extra care when riding a motorcycle
that has added cargo or accessories.
Here, along with the information about
accessories below, are some general
guidelines to follow if loading cargo to
your motorcycle:
The total weight of the operator, pas-
senger, accessories and cargo must
not exceed the maximum load limit.
Operation of an overloa ded vehicle
coul d cause an acci dent. When loading within this weight limit,
keep the following in mind:
 Cargo and accessory weight
should be kept as low and close to
the motorcycle as possible. Se-
curely pack your heaviest items as
close to the center of the vehicle
as possible and make sure to dis-
tribute the weight as evenly as
possible on both sides of the mo-
torcycle to minimize imbalance or
instability.
 Shifting weights can create a sud-
den imbalance. Make sure that
accessories and cargo are se-
curely attached to the motorcycle
before riding. Check accessory
mounts and cargo restraints fre-
quently.
• Properly adjust the suspension for your load (suspension-ad-
justable models only), and
check the condition and pres-
sure of your tires.
• Never attach any large or heavy items to the handlebar, front
fork, or front fender. These
items, including such cargo as
sleeping bags, duffel bags, or
Maximum loa d:
178 kg (392 lb)
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Safety information
1-4
1
tents, can create unstable han-
dling or a slow steering re-
sponse.
 This vehicle is not desi gne d to
pull a trailer or to be attached to
a si decar.
Genuine Yamaha Accessories
Choosing accessories for your vehicle
is an important decision. Genuine
Yamaha accessories, which are avail- able only from a Yamaha dealer, have
been designed, tested, and approved
by Yamaha for use on your vehicle.
Many companies with no connection
to Yamaha manufacture parts and ac-
cessories or offer other modifications
for Yamaha vehicles. Yamaha is not in
a position to test the products that
these aftermarket companies produce.
Therefore, Yamaha can neither en-
dorse nor recommend the use of ac-
cessories not sold by Yamaha or
modifications not specifically recom-
mended by Yamaha, even if sold and
installed by a Yamaha dealer. Aftermarket Parts, Accessories, an
d
Mo difications
While you may find aftermarket prod-
ucts similar in design and quality to
genuine Yamaha accessories, recog-
nize that some aftermarket accesso-
ries or modifications are not suitable
because of potential safety hazards to
you or others. Installing aftermarket
products or having other modifications
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
related to changes in the vehicle.
Keep the following guidelines in mind,
as well as those provided under “Load-
ing” when mounting accessories.  Never install accessories or carry
cargo that would impair the per-
formance of your motorcycle.
Carefully inspect the accessory
before using it to make sure that it
does not in any way reduce
ground clearance or cornering
clearance, limit suspension travel, steering travel or control opera-
tion, or obscure lights or reflec-
tors.
• Accessories fitted to the han- dlebar or the front fork area can
create instability due to improp-
er weight distribution or aerody-
namic changes. If accessories
are added to the handlebar or
front fork area, they must be as
lightweight as possible and
should be kept to a minimum.
• Bulky or large accessories may seriously affect the stability of
the motorcycle due to aerody-
namic effects. Wind may at-
tempt to lift the motorcycle, or
the motorcycle may become
unstable in cross winds. These
accessories may also cause in-
stability when passing or being
passed by large vehicles.
• Certain accessories can dis- place the operator from his or
her normal riding position. This
improper position limits the
freedom of movement of the
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Safety information
1-5
1operator and may limit control
ability, therefore, such accesso-
ries are not recommended.
 Use caution when adding electri-
cal accessories. If electrical ac-
cessories exceed the capacity of
the motorcycle’s electrical sys-
tem, an electric failure could re-
sult, which could cause a
dangerous loss of lights or engine
power.
Aftermarket Tires an d Rims
The tires and rims that came with your
motorcycle were designed to match
the performance capabilities and to
provide the best combination of han-
dling, braking, and comfort. Other
tires, rims, sizes, and combinations
may not be appropriate. See page 6-17
for tire specifications and for informa-
tion on servicing and replacing your
tires.
Transportin g the Motorcycle
Be sure to observe following instruc-
tions before transporting the motorcy-
cle in another vehicle. 
Remove all loose items from the
motorcycle.
 Check that the fuel cock (if
equipped) is in the off position and
that there are no fuel leaks.
 Shift the transmission into gear
(for models with a manual trans-
mission).
 Secure the motorcycle with tie-
downs or suitable straps that are
attached to solid parts of the mo-
torcycle, such as the frame or up-
per front fork triple clamp (and not,
for example, to rubber-mounted
handlebars or turn signals, or
parts that could break). Choose
the location for the straps carefully
so the straps will not rub against
painted surfaces during transport.
 The suspension should be com-
pressed somewhat by the tie-
downs, if possible, so that the mo-
torcycle will not bounce exces-
sively during transport.
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Description
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EAU10411
Left view
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3
4
6
5
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98
1. Fuel tank cap (page 3-16)
2. Battery (page 6-30)
3. Fuses (page 6-31)
4. Tool kit (page 6-2)
5. Sidestand (page 3-20)
6. Air filter check hose
7. Shift pedal (page 3-14)
8. Idle adjusting screw (page 6-15)9. Coolant reservoir (page 6-13)
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Description
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EAU10421
Right view
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4
5
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7
1. Rear turn signal lights (page 6-33)
2. Seat lock (page 3-19)
3. Front turn signal light (page 6-33)
4. Engine oil filter element (page 6-10)
5. Dipstick (page 6-10)
6. Brake pedal (page 3-14)
7. Rear brake fluid reservoir (page 6-22)UB6GE1E0.book Page 2 Thursday, July 30, 2020 1:08 PM

Description
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EAU10431
Controls and instruments
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2
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4
5
6
7
8
1. Clutch lever (page 3-13)
2. Left handlebar switches (page 3-12)
3. Multi-function meter unit (page 3-4)
4. Main switch/steering lock (page 3-1)
5. Front brake fluid reservoir (page 6-22)
6. Right handlebar switches (page 3-12)
7. Throttle grip (page 6-16)
8. Brake lever (page 3-14)
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Instrument and control functions
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EAU10462
Main switch/steerin g lockThe main switch/steering lock controls
the ignition and lighting systems, and is
used to lock the steering. The various
positions are described below.
EAU85050
ON
All electrical circuits are supplied with
power and the vehicle lights are turned
on. The engine can be started. The key
cannot be removed.TIP To prevent battery discharge, do
not leave the key in the on position
without the engine running.
 The headlight comes on automat-
ically when the engine is started. 
The headlight will stay on until the
key is turned to “OFF”, even if the
engine stalls.
EAU10662
OFF
All electrical systems are off. The key
can be removed.
WARNING
EWA10062
Never turn the key to “OFF” or
“LOCK” while the vehicle is movin g.
Otherwise the electrical systems will
b e switche d off, which may result in
loss of control or an acci dent.
EAU10696
LOCK
The steering is locked and all electrical
systems are off. The key can be re-
moved. To lock the steering
1. Turn the handlebars all the way to
the left or right.
2. With the key in the “OFF” position, push the key in and turn it to
“LOCK”.
3. Remove the key.TIPIf the steering will not lock, try turning
the handlebars back to the right or left
slightly.1. Push.
2. Turn.12
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