check engine 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
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Safety information
1-3
1 Avoid Carbon Monoxide Poisoning
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.
Loading
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. Useextra 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 overloaded vehicle
could cause an accident.
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
Maximum load:
180 kg (397 lb)
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Safety information
1-5
1 operator 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 and 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 6-15
for tire specifications and for informa-
tion on servicing and replacing your
tires.
Transporting 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-mountedhandlebars 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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Instrument and control functions
3-3
3 For vehicles with a radiator fan, the ra-
diator fan(s) automatically switch on or
off according to the coolant tempera-
ture.
TIP
When the vehicle is turned on, the light
will come on for a few seconds, and
then go off. If the light does not come
on, or if the light remains on, have a
Yamaha dealer check the vehicle.
NOTICE
ECA10022
Do not continue to operate the en-
gine if it is overheating.
EAU73172Engine trouble warning light “ ”
This warning light comes on if a prob-
lem is detected in the engine or other
vehicle control system. If this occurs,
have a Yamaha dealer check the on-
board diagnostic system.
TIP
When the vehicle is turned on, the light
will come on for a few seconds and
then go off. If the light does not come
on, or if the light remains on, have a
Yamaha dealer check the vehicle.
EAU69895ABS warning light “ ”
This warning light comes on when the
vehicle is first turned on, and goes off
after starting riding. If the warning light
comes on while riding, the anti-lock
brake system may not work correctly.
WARNING
EWA16043
If the ABS warning light does not
turn off after reaching 10 km/h (6
mi/h), or if the warning light comes
on while riding:
Use extra caution to avoid pos-
sible wheel lock during emer-
gency braking.
Have a Yamaha dealer check
the vehicle as soon as possible.
EAU80372Shift light
This light can be set to come on and go
off at select engine speeds. (See page
3-9.)
TIP
When the vehicle is turned on, the light
will come on for a few seconds and
then go off. If the light does not come
on, have a Yamaha dealer check the
vehicle.
ABS
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Instrument and control functions
3-5
3 4. Use the “RESET” button to set the
minutes.
5. Push the “SELECT” button to start
the clock.
Fuel meter
The fuel meter indicates the amount of
fuel in the fuel tank. The display seg-
ments of the fuel meter disappear to-
wards “E” (empty) as the fuel level
decreases. When the last segment
start flashing, refuel as soon as possi-
ble.
When the key is turned to “ ”, the dis-
play segments of the fuel meter will
sweep once across the fuel level range
and then return to the current amount
in order to test the electrical circuit.
TIP
The fuel meter is equipped with a self-
diagnosis function. If a problem is de-
tected in the fuel meter electrical cir-
cuit, the fuel meter will flash
repeatedly. If this occurs, have a
Yamaha dealer check the vehicle.
VVA indicator
This model is equipped with variable
valve actuation (VVA) for good fuel
economy and acceleration in both the
low-speed and high-speed ranges.
The VVA indicator comes on when the
variable valve actuation system has
switched to the high-speed range.
Tachometer
The tachometer allows the rider to
monitor the engine speed and keep it
within the ideal power range.
NOTICE
ECA23050
Do not operate the engine in the ta-
chometer high-r/min zone.
High-r/min zone: 11000 r/min and
above
1. Fuel meter
ZAUM15701
1. VVA (variable valve actuation) indicator
1. Tachometer
2. Tachometer red zone
ZAUM1571
1
ZAUM1572
1
2
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Instrument and control functions
3-11
3 To set the user name
1. Turn the key to “ ”.
2. Push and hold the “RESET” but-
ton.
3. Turn the key to “ ”, and then re-
lease the “RESET” button after
four seconds.
4. When the first character starts
flashing, push the “SELECT” but-
ton to display the next alpha nu-
merical character, push the
“RESET” button to switch to the
previous character.
5. Push and hold the “SELECT” but-
ton to confirm the selected char-
acter. The second character will
start flashing. Repeat this process
for all six characters. After the
sixth character is set, all charac-
ters will flash twice and the setting
mode will automatically end.Self-diagnosis device
This model is equipped with a self-di-
agnosis device for various electrical
circuits.
If a problem is detected in any of those
circuits, the engine trouble warning
light will come on and the display will
indicate an error code.
If the display indicates any error codes,
note the code number, and then have a
Yamaha dealer check the vehicle.
NOTICE
ECA11591
If the display indicates an error
code, the vehicle should be checked
as soon as possible in order to avoid
engine damage.
1. Hyphen
2. Space
ZAUM1581
AB C Y Z
0 1 2 9
-_
12
1. Self-diagnosis device
ZAUM15821
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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
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Instrument and control functions
3-21
3
EAU83150
Ignition circuit cut-off system
This system prevents in-gear engine
starts unless the clutch lever is pulled
and the sidestand is up. Also, it will
stop the running engine should the
sidestand be lowered while the trans-
mission is in gear.
Periodically check the system via the
following procedure.
TIP
This check is most reliable if per-
formed with a warmed-up engine.
See pages 3-1 and 3-12 for switch
operation information.
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Instrument and control functions
3-22
3
With the engine turned off:
1. Move the sidestand down.
2.Set engine stop switch to run position.
3. Turn main switch to on position.
4.Shift transmission into neutral.
5. Push the start switch.
Does the engine start?
With the engine still running:
6. Move the sidestand up.
7. Pull the clutch lever.
8.Shift transmission into gear.
9. Move the sidestand down.
Does the engine stall?
After the engine has stalled:
10. Move the sidestand up.
11. Pull the clutch lever.
12. Push the start switch.
Does the engine start?
The system is OK. The motorcycle can
be ridden.
The neutral switch may not be working.
The motorcycle should not be ridden
until checked by a Yamaha dealer.
The sidestand switch may not be
working.
The motorcycle should not be ridden
until checked by a Yamaha dealer.
The clutch switch may not be working.
The motorcycle should not be ridden
until checked by a Yamaha dealer.
WARNING
If a malfunction is found, have the
vehicle inspected before riding.
YES NO
YES NO
YES NO
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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
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