2020 YAMAHA MT-125 valve

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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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
3-17
3 dry, soft cloth, since fuel may
deteriorate painted surfaces or
plastic parts.
[ECA10072]
4. Be sure to securely close the fuel
tank cap.
WARNING
EWA15152
Gasoline is poisonous and can
cause injury or death. Handle gaso-
line with care. Never siphon gasoline
by mouth. If you should swallow
some gasoline or inhale a lot of gas-
oline vapor, or get some gasoline in
your eyes, see your doctor immedi-
ately. If gasoline spills on your skin,
wash with soap and water. If gaso-
line spills on your clothing, change
your clothes.
EAU86072
Your Yamaha engine was designed to
use unleaded gasoline with a research
octane number of 95 or higher. If en-
gine knocking or pinging occurs, use a
gasoline of a different brand or higher
octane rating.
TIP
This mark identifies the recom-
mended fuel for this vehicle as
specified by European regulation
(EN228).
Confirm the gasoline pump nozzle
has the same fuel identification
mark.
Gasohol
There are two types of gasohol: gaso-
hol containing ethanol and that con-
taining methanol. Gasohol containing
ethanol can be used if the ethanol con-
tent does not exceed 10% (E10). Gas-
ohol containing methanol is not
recommended by Yamaha because it
can cause damage to the fuel system
or vehicle performance problems.
NOTICE
ECA11401
Use only unleaded gasoline. The use
of leaded gasoline will cause severe
damage to internal engine parts,
such as the valves and piston rings,
as well as to the exhaust system.
Recommended fuel:
Unleaded gasoline (E10 acceptable)
Octane number (RON):
95
Fuel tank capacity:
10 L (2.6 US gal, 2.2 Imp.gal)
Fuel tank reserve:
3.0 L (0.79 US gal, 0.66 Imp.gal)
E5E10
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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
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Periodic maintenance and adjustment
6-15
6
EAU21403
Valve clearance
The valves are an important engine
component, and since valve clearance
changes with use, they must be
checked and adjusted at the intervals
specified in the periodic maintenance
chart. Unadjusted valves can result in
improper air-fuel mixture, engine
noise, and eventually engine damage.
To prevent this from occurring, have
your Yamaha dealer check and adjust
the valve clearance at regular intervals.
TIP
This service must be performed when
the engine is cold.
EAU77621
Tires
Tires are the only contact between the
vehicle and the road. Safety in all con-
ditions of riding depends on a relatively
small area of road contact. Therefore, it
is essential to maintain the tires in good
condition at all times and replace them
at the appropriate time with the speci-
fied tires.
Tire air pressure
The tire air pressure should be
checked and, if necessary, adjusted
before each ride.
WARNING
EWA10504
Operation of this vehicle with im-
proper tire pressure may cause se-
vere injury or death from loss of
control.
The tire air pressure must be
checked and adjusted on cold
tires (i.e., when the temperature
of the tires equals the ambient
temperature).
The tire air pressure must be
adjusted in accordance with the
riding speed and with the total
weight of rider, passenger, car-
go, and accessories approved
for this model.
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Periodic maintenance and adjustment
6-16
6
WARNING
EWA10512
Never overload your vehicle. Opera-
tion of an overloaded vehicle could
cause an accident.
Tire inspection
The tires must be checked before each
ride. If the center tread depth reaches
the specified limit, if the tire has a nail
or glass fragments in it, or if the side-
wall is cracked, have a Yamaha dealer
replace the tire immediately.
TIP
The tire tread depth limits may differ
from country to country. Always com-
ply with the local regulations.
WARNING
EWA10472
Have a Yamaha dealer replace
excessively worn tires. Besides
being illegal, operating the vehi-
cle with excessively worn tires
decreases riding stability and
can lead to loss of control.
The replacement of all wheel
and brake-related parts, includ-
ing the tires, should be left to a
Yamaha dealer, who has the
necessary professional knowl-
edge and experience to do so.
Ride at moderate speeds after
changing a tire since the tire
surface must first be “broken
in” for it to develop its optimal
characteristics.
Tire information
Cold tire air pressure:
1 person:
Front:
200 kPa (2.00 kgf/cm², 29 psi)
Rear:
220 kPa (2.20 kgf/cm², 32 psi)
2 persons:
Front:
200 kPa (2.00 kgf/cm², 29 psi)
Rear:
220 kPa (2.20 kgf/cm², 32 psi)
Maximum load:
Vehicle:
180 kg (397 lb)
The vehicle’s maximum load is the
combined weight of the rider, pas-
senger, cargo, and any accessories.
1. Tire sidewall
2. Tire tread depth
Minimum tire tread depth (front and
rear):
1.6 mm (0.06 in)
1. Tire air valve
2. Tire air valve core
3. Tire air valve cap with seal
123
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Periodic maintenance and adjustment
6-17
6 This model is equipped with tubeless
tires and tire air valves.
Tires age, even if they have not been
used or have only been used occasion-
ally. Cracking of the tread and sidewall
rubber, sometimes accompanied by
carcass deformation, is an evidence of
ageing. Old and aged tires shall be
checked by tire specialists to ascertain
their suitability for further use.
WARNING
EWA16101
The front and rear tires should
be of the same make and de-
sign, otherwise the handling
characteristics of the vehicle
may be different, which could
lead to an accident.
Always make sure that the valve
caps are securely installed to
prevent air pressure leakage.
Use only the tire valves and
valve cores listed below to
avoid tire deflation during a ride.
After extensive tests, only the tires list-
ed below have been approved for this
model by Yamaha.
Front tire:
Size:
100/80-17M/C 52S
Manufacturer/model:
MICHELIN PILOT STREET
Tire air valve:
TR412
Valve core:
V3002 (original)
Rear tire:
Size:
140/70-17M/C 66S
Manufacturer/model:
MICHELIN PILOT STREET
Tire air valve:
TR412
Valve core:
V3002 (original)
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Periodic maintenance and adjustment
6-22
6
EAU40262
Checking the brake fluid level
Before riding, check that the brake fluid
is above the minimum level mark.
Check the brake fluid level with the top
of the reservoir level. Replenish the
brake fluid if necessary.
Front brake
Rear brake
WARNING
EWA16011
Improper maintenance can result in
loss of braking ability. Observe
these precautions:
Insufficient brake fluid may al-
low air to enter the brake sys-
tem, reducing braking
performance.Clean the filler cap before re-
moving. Use only DOT 4 brake
fluid from a sealed container.
Use only the specified brake flu-
id; otherwise, the rubber seals
may deteriorate, causing leak-
age.
Refill with the same type of
brake fluid. Adding a brake fluid
other than DOT 4 may result in a
harmful chemical reaction.
Be careful that water or dust
does not enter the brake fluid
reservoir when refilling. Water
will significantly lower the boil-
ing point of the fluid and may re-
sult in vapor lock, an
d dirt may
clog the ABS hydraulic unit
valves.
NOTICE
ECA17641
Brake fluid may damage painted
surfaces or plastic parts. Always
clean up spilled fluid immediately.
As the brake pads wear, it is normal for
the brake fluid level to gradually go
down. A low brake fluid level may indi-
cate worn brake pads and/or brake
system leakage; therefore, be sure to
check the brake pads for wear and the
brake system for leakage. If the brake
fluid level goes down suddenly, have a
Yamaha dealer check the cause before
further riding.
1. Minimum level mark
1. Minimum level mark
Specified brake fluid:
DOT 4
1
ZAUM1057
1
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