maintenance YAMAHA MT-125 2020 Owners Manual

Table of contents
Safety information............................1-1
Description........................................2-1
Left view ..........................................2-1
Right view........................................2-2
Controls and instruments ................2-3
Instrument and 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 .....................................3-13
Brake lever ....................................3-14
Brake pedal ...................................3-14
ABS ...............................................3-15
Fuel tank cap.................................3-16
Fuel................................................3-16
Fuel tank overflow hose ................3-18
Catalytic converter ........................3-18
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 and important riding
points.................................................5-1
Engine break-in ...............................5-1
Starting the engine ..........................5-2
Shifting ............................................5-4
Tips for reducing fuel
consumption ................................5-5
Parking ............................................5-6
Periodic maintenance and
adjustment........................................6-1
Tool kit.............................................6-2
Periodic maintenance chart for the
emission control system ..............6-3
General maintenance and
lubrication chart ...........................6-4Removing and installing
cowlings ...................................... 6-7
Checking the spark plug ................. 6-7
Engine oil and oil filter element ....... 6-8
Why Yamalube .............................. 6-11
Coolant ......................................... 6-11
Replacing the air filter element
and cleaning the check hose..... 6-13
Adjusting the engine idling
speed......................................... 6-13
Adjusting the throttle grip free
play ............................................ 6-14
Valve clearance ............................. 6-15
Tires .............................................. 6-15
Cast wheels .................................. 6-18
Adjusting the clutch lever free
play ............................................ 6-18
Checking the front brake lever
free play ..................................... 6-19
Adjusting the brake pedal free
play ............................................ 6-20
Brake light switches ...................... 6-20
Checking the front and rear brake
pads........................................... 6-21
Checking the brake fluid level....... 6-22
Changing the brake fluid............... 6-23
Drive chain slack ........................... 6-23
Cleaning and lubricating the drive
chain .......................................... 6-25
Checking and lubricating the
cables ........................................ 6-25
Checking and lubricating the
throttle grip and cable ............... 6-26
Checking and lubricating the
brake and shift pedals ............... 6-26
Checking and lubricating the
brake and clutch levers ............. 6-27
Checking and lubricating the
sidestand ................................... 6-27
Lubricating the swingarm pivots... 6-28
Checking the front fork ................. 6-28
Checking the steering ................... 6-29
Checking the wheel bearings ....... 6-29
Battery .......................................... 6-30
Replacing the fuses ...................... 6-31
Vehicle lights ................................. 6-32
UB6GE0E0.book Page 1 Wednesday, August 28, 2019 11:11 AM

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 Riding
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 ofan 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.
UB6GE0E0.book Page 1 Wednesday, August 28, 2019 11:11 AM

Instrument and control functions
3-18
3
EAU58301
Fuel tank overflow hose
Before operating the vehicle:
Check the fuel tank overflow hose
connection and routing.
Check the fuel tank overflow hose
for cracks or damage, and replace
it if necessary.
Make sure that the fuel tank over-
flow hose is not blocked, and
clean it if necessary.
EAU13435
Catalytic converter
The exhaust system contains catalytic
converter(s) to reduce harmful exhaust
emissions.
WARNING
EWA10863
The exhaust system is hot after op-
eration. To prevent a fire hazard or
burns:
Do not park the vehicle near
possible fire hazards such as
grass or other materials that
easily burn.
Park the vehicle in a place
where pedestrians or children
are not likely to touch the hot
exhaust system.
Make sure that the exhaust sys-
tem has cooled down before
doing any maintenance work.
Do not allow the engine to idle
more than a few minutes. Long
idling can cause a build-up of
heat.
1. Fuel tank overflow hose
1
UB6GE0E0.book Page 18 Wednesday, August 28, 2019 11:11 AM

For your safety – pre-operation checks
4-1
4
EAU63441
Inspect your vehicle each time you use it to make sure the vehicle is in safe oper-
ating condition. Always follow the inspection and maintenance procedures and
schedules described in the Owner’s Manual.
WARNING
EWA11152
Failure to inspect or maintain the vehicle properly increases the possibility
of an accident or equipment damage. Do not operate the vehicle if you find
any problem. If a problem cannot be corrected by the procedures provided
in this manual, have the vehicle inspected by a Yamaha dealer.
Before using this vehicle, check the following points:
ITEM CHECKS PAGE
Fuel• Check fuel level in fuel tank.
• Refuel if necessary.
• Check fuel line for leakage.
• Check fuel tank overflow hose for obstructions, cracks
or damage, and check hose connection.3-16,
3-18
Engine oil• Check oil level in engine.
• If necessary, add recommended oil to specified level.
• Check vehicle for oil leakage.6-8
Coolant• Check coolant level in reservoir.
• If necessary, add recommended coolant to specified
level.
• Check cooling system for leakage.6-11
Front brake• Check operation.
• If soft or spongy, have Yamaha dealer bleed hydraulic
system.
• Check brake pads for wear.
• Replace if necessary.
• Check fluid level in reservoir.
• If necessary, add specified brake fluid to specified level.
• Check hydraulic system for leakage.6-21,
6-22
Rear brake• Check operation.
• If soft or spongy, have Yamaha dealer bleed hydraulic
system.
• Check brake pads for wear.
• Replace if necessary.
• Check fluid level in reservoir.
• If necessary, add specified brake fluid to specified level.
• Check hydraulic system for leakage.6-21,
6-22
Clutch• Check operation.
• Lubricate cable if necessary.
• Check lever free play.
• Adjust if necessary.6-18
UB6GE0E0.book Page 1 Wednesday, August 28, 2019 11:11 AM

Periodic maintenance and adjustment
6-1
6
EAU17246
Periodic inspection, adjustment, and
lubrication will keep your vehicle in the
safest and most efficient condition
possible. Safety is an obligation of the
vehicle owner/operator. The most im-
portant points of vehicle inspection,
adjustment, and lubrication are ex-
plained on the following pages.
The intervals given in the periodic
maintenance charts should be simply
considered as a general guide under
normal riding conditions. However, de-
pending on the weather, terrain, geo-
graphical location, and individual use,
the maintenance intervals may need to
be shortened.
WARNING
EWA10322
Failure to properly maintain the vehi-
cle or performing maintenance ac-
tivities incorrectly may increase
your risk of injury or death during
service or while using the vehicle. If
you are not familiar with vehicle ser-
vice, have a Yamaha dealer perform
service.
WARNING
EWA15123
Turn off the engine when performing
maintenance unless otherwise
specified.
A running engine has moving
parts that can catch on body
parts or clothing and electrical
parts that can cause shocks or
fires.
Running the engine while ser-
vicing can lead to eye injury,
burns, fire, or carbon monoxide
poisoning – possibly leading todeath. See page 1-3 for more in-
formation about carbon monox-
ide.
WARNING
EWA15461
Brake discs, calipers, drums, and
linings can become very hot during
use. To avoid possible burns, let
brake components cool before
touching them.
UB6GE0E0.book Page 1 Wednesday, August 28, 2019 11:11 AM

Periodic maintenance and adjustment
6-2
6
EAU17303
Emission controls not only function to
ensure cleaner air, but are also vital to
proper engine operation and maximum
performance. In the following periodic
maintenance charts, the services relat-
ed to emissions control are grouped
separately. These services require
specialized data, knowledge, and
equipment. Maintenance, replace-
ment, or repair of the emission control
devices and systems may be per-
formed by any repair establishment or
individual that is certified (if applicable).
Yamaha dealers are trained and
equipped to perform these particular
services.
EAU85230
Tool kit
The tool kit is in the location shown.
The information included in this manual
and the tools provided in the tool kit are
intended to assist you in the perfor-
mance of preventive maintenance and
minor repairs. However, a torque
wrench and other tools are necessary
to perform certain maintenance work
correctly.
TIP
If you do not have the tools or experi-
ence required for a particular job, have
your Yamaha dealer perform it for you.
1. Tool kit
1
UB6GE0E0.book Page 2 Wednesday, August 28, 2019 11:11 AM

Periodic maintenance and adjustment
6-3
6
EAU71021
TIP
The annual checks must be performed every year, except if a distance-
based maintenance is performed instead.
From 30000 km (17500 mi), repeat the maintenance intervals starting from
6000 km (3500 mi).
Items marked with an asterisk should be performed by a Yamaha dealer as
they require special tools, data and technical skills.
EAU71060
Periodic maintenance chart for the emission control system
NO. ITEM
1*Fuel line• Check fuel hoses for cracks or
damage.
• Replace if necessary.√√√√√
2*Spark plug• Check condition.
• Adjust gap and clean.√√
• Replace.√√
3*Valve clearance• Check and adjust.√√√√
4*Fuel injection• Check and adjust engine idle
speed.√√√√√√
5*Exhaust system• Check for leakage.
• Tighten if necessary.
• Replace gasket if necessary.√√√√√X 1000 km CHECK OR
MAINTENANCE JOB
X 1000 mi
ODOMETER
READING
ANNUAL CHECK
16121824
0.63.5710.514
UB6GE0E0.book Page 3 Wednesday, August 28, 2019 11:11 AM

Periodic maintenance and adjustment
6-4
6
EAU71361
General maintenance and lubrication chart
NO. ITEM
1*Diagnostic system
check• Perform dynamic inspection us-
ing Yamaha diagnostic tool.
• Check the error codes.√√√√√√
2*Air filter element• Replace.√√
3Air filter case
check hose• Clean.√√√√√
4Clutch• Check operation.
•Adjust.√√√√√
5*Front brake• Check operation, fluid level, and
for fluid leakage.
• Replace brake pads if neces-
sary.√√√√√√
6*Rear brake• Check operation, fluid level, and
for fluid leakage.
• Replace brake pads if neces-
sary.√√√√√√
7*Brake hoses• Check for cracks or damage.√√√√√
• Replace. Every 4 years
8*Brake fluid• Change. Every 2 years
9*Wheels• Check runout and for damage.
• Replace if necessary.√√√√
10*Tires• Check tread depth and for dam-
age.
• Replace if necessary.
• Check air pressure.
• Correct if necessary.√√√√√
11*Wheel bearings• Check bearing for looseness or
damage.√√√√
12*Swingarm pivot
bearings• Check operation and for exces-
sive play.√√√√
• Lubricate with lithium-soap-
based grease.Every 24000 km (14000 mi)X 1000 km CHECK OR
MAINTENANCE JOB
X 1000 miODOMETER
READINGANNUAL CHECK
1 6 12 18 24
0.6 3.5 7 10.5 14
UB6GE0E0.book Page 4 Wednesday, August 28, 2019 11:11 AM

Periodic maintenance and adjustment
6-5
6
13 Drive chain• Check chain slack, alignment
and condition.
• Adjust and lubricate chain with a
special O-ring chain lubricant
thoroughly.Every 1000 km (600 mi) and af-
ter washing the motorcycle, rid-
ing in the rain or riding in wet
areas
14*Steering bearings• Check bearing assemblies for
looseness.√√√√
• Moderately repack with lithium-
soap-based grease.√
15*Chassis fasteners• Make sure that all nuts, bolts
and screws are properly tight-
ened.√√√√√
16Brake lever pivot
shaft• Lubricate with silicone grease.√√√√√
17Brake pedal pivot
shaft• Lubricate with lithium-soap-
based grease.√√√√√
18Clutch lever pivot
shaft• Lubricate with lithium-soap-
based grease.√√√√√
19Shift pedal pivot
shaft• Lubricate with lithium-soap-
based grease.√√√√√
20 Sidestand• Check operation.
• Lubricate with lithium-soap-
based grease.√√√√√
21*Sidestand switch• Check operation and replace if
necessary.√√√√√√
22*Front fork• Check operation and for oil leak-
age.
• Replace if necessary.√√√√
23*Shock absorber
assembly• Check operation and for oil leak-
age.
• Replace if necessary.√√√√
24*Rear suspension
relay arm and
con-
necting arm pivot-
ing points• Check operation.√√√√
• Lubricate with lithium-soap-
based grease.√√
25 Engine oil• Change (warm engine before
draining).
• Check oil level and vehicle for oil
leakage.At the initial interval and
every 3000 km (1800 mi)
thereafter.√ NO. ITEM
X 1000 km CHECK OR
MAINTENANCE JOB
X 1000 mi
ODOMETER
READING
ANNUAL CHECK
16121824
0.63.5710.514
UB6GE0E0.book Page 5 Wednesday, August 28, 2019 11:11 AM

Periodic maintenance and adjustment
6-6
6
EAU72750
TIP
The air filter needs more frequent service if you are riding in unusually wet or
dusty areas.
Hydraulic brake service
• Regularly check and, if necessary, correct the brake fluid level.
• Every two years replace the internal components of the brake master cyl-
inders and calipers, and change the brake fluid.
• Replace the brake hoses every four years and if cracked or damaged.
26Engine oil filter el-
ement• Replace.√√√√√
27*Cooling system• Check coolant level and vehicle
for coolant leakage.√√√√√
• Change. Every 3 years
28*Front and rear
brake switches• Check operation.√√√√√√
29*Moving parts and
cables• Lubricate.√√√√√
30*Throttle grip hous-
ing and cable• Check operation and free play.
• Adjust the throttle cable free
play if necessary.
• Lubricate the throttle grip hous-
ing and cable.√√√√√
31*Lights, signals and
switches• Check operation.
• Adjust headlight beam.√√√√√√ NO. ITEM
X 1000 km CHECK OR
MAINTENANCE JOB
X 1000 miODOMETER
READING
ANNUAL CHECK
16121824
0.6 3.5 7 10.5 14
UB6GE0E0.book Page 6 Wednesday, August 28, 2019 11:11 AM