2021 YAMAHA MT-125 Owners Manual

PANTONE285C
MTN125-A (MT-125)
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B6G-F8199-E1
Read this manual carefully
before operating this vehicle.
MOTORCYCLE
OWNER’S MANUAL
Specifications
Consumer information
Motorcycle care and storage
Periodic maintenance and adjustment
For your safety – pre-operation checks
Instrument and control functions Description
Safety information
Operation and important riding points
Index
[English (E)]

EAU46094
Read this manual carefully before operatin g this vehicle. This manual shoul d stay with this vehicle if it is sol d.
UB6GE1E0.book Page 1 Thursday, July 30, 2020 1:08 PM

Introduction
EAU10103
Welcome to the Yamaha world of motorcycling!
As the owner of the MTN125-A, you are benefiting from Yamaha’s vast experience and newest technology regarding the
design and manufacture of high-quality products, which have earned Yamaha a reputation for dependability.
Please take the time to read this manual thoroughly, so as to enjoy all advantages of your MTN125-A. The Owner’s Manual
does not only instruct you in how to operate, inspect and maintain your motorcycle, but also in how to safeguard yourself
and others from trouble and injury.
In addition, the many tips given in this manual will help keep your motorcycle in the best possible condition. If you have any
further questions, do not hesitate to contact your Yamaha dealer.
The Yamaha team wishes you many safe and pleasant rides. So, remember to put safety first!
Yamaha continually seeks advancements in product design and quality. Therefore, while this manual contains the most cur- rent product information available at the time of printing, there may be minor discrepancies between your motorcycle and
this manual. If there is any question concerning this manual, please consult a Yamaha dealer.
WARNING
EWA10032
Please rea d this manual carefully an d completely before operatin g this motorcycle.
UB6GE1E0.book Page 1 Thursday, July 30, 2020 1:08 PM

Important manual information
EAU10134
Particularly important information is distinguished in this manual by the following notations:
*Product and specifications are subject to change without notice.This is the safety alert sym
bol. It is use d to alert you to potential personal injury
hazar ds. Ob ey all safety messa ges that follow this sym bol to avoi d possi ble injury
or death.
A WARNING in dicates a hazar dous situation which, if not avoi ded , coul d result in
d eath or serious injury.
A NOTICE in dicates special precautions that must be taken to avoi d d ama ge to the
vehicle or other property.
A TIP provides key information to make procedures easier or clearer.
WARNING
NOTICETIP
UB6GE1E0.book Page 1 Thursday, July 30, 2020 1:08 PM

Important manual information
EAUM1013
MTN125-A
OWNER’S MANUAL
©2021 by MBK INDUSTRIE
1st e dition, Septem ber 2020
All ri ghts reserve d
Any reprintin g or unauthorize d use
without the written permission of
MBK INDUSTRIE
is expressly prohi bite d.
Printe d in France.
UB6GE1E0.book Page 2 Thursday, July 30, 2020 1:08 PM

Table of contentsSafety information ............................ 1-1
Description ....................................... 2-1
Left view ......................................... 2-1
Right view ....................................... 2-2
Controls and instruments ............... 2-3
Instrument an d control functions ... 3-1
Main switch/steering lock............... 3-1
Indicator lights and warning lights............................................ 3-2
Multi-function meter unit ................ 3-4
Handlebar switches ...................... 3-12
Clutch lever .................................. 3-13
Shift pedal .................................... 3-14
Brake lever.................................... 3-14
Brake pedal .................................. 3-14
ABS .............................................. 3-15
Fuel tank cap ................................ 3-16
Fuel ............................................... 3-16
Fuel tank breather hose and overflow hose ............................ 3-18
Catalytic converter ....................... 3-19
Seat .............................................. 3-19
Helmet holder ............................... 3-20
Sidestand ..................................... 3-20
Ignition circuit cut-off system ....... 3-21 For your safety – pre-operation
checks
............................................... 4-1
Operation an d important ri din g
points ................................................. 5-1
Engine break-in ............................... 5-1
Starting the engine .......................... 5-2
Shifting ............................................ 5-3
Tips for reducing fuel consumption ................................ 5-4
Parking ............................................ 5-4
Perio dic maintenance an d
a d justment ........................................ 6-1
Tool kit ............................................ 6-2
Periodic maintenance chart for the emission control system .............. 6-3
General maintenance and lubrication chart ........................... 6-4
Removing and installing cowlings... 6-8
Checking the spark plug ................. 6-8
Canister ........................................... 6-9
Engine oil and oil filter element ..... 6-10
Why Yamalube .............................. 6-12
Coolant.......................................... 6-13
Replacing the air filter element
and cleaning the check hose..... 6-14
Adjusting the engine idling speed ......................................... 6-15
Adjusting the throttle grip free play ............................................ 6-16 Valve clearance............................. 6-16
Tires .............................................. 6-17
Cast wheels .................................. 6-19
Adjusting the clutch lever free
play ............................................ 6-19
Checking the front brake lever free play..................................... 6-20
Adjusting the brake pedal free
play ............................................ 6-21
Brake light switches ..................... 6-21
Checking the front and rear brake pads .......................................... 6-22
Checking the brake fluid level ...... 6-22
Changing the brake fluid .............. 6-24
Drive chain slack........................... 6-24
Cleaning and lubricating the drive chain.......................................... 6-25
Checking and lubricating the cables ........................................ 6-26
Checking and lubricating the
throttle grip and cable ............... 6-26
Checking and lubricating the brake and shift pedals............... 6-27
Checking and lubricating the brake and clutch levers ............. 6-27
Checking and lubricating the
sidestand................................... 6-28
Lubricating the rear suspension ... 6-28
Checking the front fork ................. 6-29
Checking the steering................... 6-29
Checking the wheel bearings ....... 6-30UB6GE1E0.book Page 1 Thursday, July 30, 2020 1:08 PM

Table of contents
Battery ...........................................6-30
Replacing the fuses .......................6-31
Vehicle lights .................................6-32
Tail/brake light ...............................6-32
Replacing a turn signal light
bulb ............................................6-33
Replacing the license plate light bulb ............................................6-33
Supporting the motorcycle............6-34
Troubleshooting ............................6-34
Troubleshooting chart ...................6-35
Motorcycle care an d stora ge ..........7-1
Matte color caution .........................7-1
Care .................................................7-1
Storage ............................................7-3
Specifications ....................................8-1
Consumer information .....................9-1
Identification numbers .....................9-1
Diagnostic connector ......................9-2
Vehicle data recording ....................9-2
In dex ................................................10-1
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1-1
1
Safety information
EAU1028C
Be a Responsible Owner
As the vehicle’s owner, you are re-
sponsible for the safe and proper oper-
ation of your motorcycle.
Motorcycles are single-track vehicles.
Their safe use and operation are de-
pendent upon the use of proper riding
techniques as well as the expertise of
the operator. Every operator should
know the following requirements be-
fore riding this motorcycle.
He or she should:  Obtain thorough instructions from
a competent source on all aspects
of motorcycle operation.
 Observe the warnings and mainte-
nance requirements in this Own-
er’s Manual.
 Obtain qualified training in safe
and proper riding techniques.
 Obtain professional technical ser-
vice as indicated in this Owner’s
Manual and/or when made neces-
sary by mechanical conditions. 
Never operate a motorcycle with-
out proper training or instruction.
Take a training course. Beginners
should receive training from a cer-
tified instructor. Contact an autho-
rized motorcycle dealer to find out
about the training courses nearest
you.
Safe Ri din g
Perform the pre-operation checks
each time you use the vehicle to make
sure it is in safe operating condition.
Failure to inspect or maintain the vehi-
cle properly increases the possibility of
an accident or equipment damage.
See page 4-1 for a list of pre-operation
checks.  This motorcycle is designed to
carry the operator and a passen-
ger.
 The failure of motorists to detect
and recognize motorcycles in traf-
fic is the predominating cause of
automobile/motorcycle accidents.
Many accidents have been
caused by an automobile driver
who did not see the motorcycle.
Making yourself conspicuous ap- pears to be very effective in reduc-
ing the chance of this type of
accident.
Therefore:
• Wear a brightly colored jacket.
• Use extra caution when you are approaching and passing
through intersections, since in-
tersections are the most likely
places for motorcycle accidents
to occur.
• Ride where other motorists can see you. Avoid riding in another
motorist’s blind spot.
• Never maintain a motorcycle without proper knowledge.
Contact an authorized motorcy-
cle dealer to inform you on ba-
sic motorcycle maintenance.
Certain maintenance can only
be carried out by certified staff.UB6GE1E0.book Page 1 Thursday, July 30, 2020 1:08 PM