2021 YAMAHA MT-125 engine

Instrument and control functions
3-6
3
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 en
gine in the ta-
chometer hi gh-r/min zone. Hi
gh-r/min zone: 11000 r/min an d
a b ove
Transmission gear display
This display shows the selected gear.
The neutral position is indicated by “ ”
and by the neutral indicator light. Multi-function
display
The multi-function display is equipped
with the following:  an odometer
 two tripmeters
 a fuel reserve tripmeter
 an instantaneous fuel consump-
tion display
 an average fuel consumption dis-
play
 an average speed display
 a brightness screen and shift tim-
ing indicator light control mode
 welcome screen display
 a self diagnostic device
Push the “SELECT” button to switch
the display between the odometer
mode “ODO”, tripmeters mode “TRIP
1. Tachometer
2. Tachometer red zoneZAUM1572
1 2
1. Neutral indicator light “ ”
2. Transmission gear displayZAUM15731
2
1. Multi-function displayZAUM1574
1
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Instrument and control functions
3-10
3
Bri
ghtness screen an d shift timin g
in dicator li ght control mo de
This mode cycles through five control
functions in the order listed below.  Brightness screen: the multi-func-
tion meter unit can be adjusted for
the brightness screen.
 Shift timing light flashing pattern:
this function allows you to choose
whether or not the indicator light
will come on and whether it should
flash or stay on when activated.
 Shift timing light activation point:
this function allows you to select
the engine speed at which the in-
dicator light is activated. 
Shift timing light deactivation
point: this function allows you to
select the engine speed at which
the indicator light is deactivated.
 Shift timing light brightness: this
function allows you to adjust the
brightness of the indicator light.
To adjust the brightness screen and
shift timing indicator light1. Turn the key to “ ”.
2. Push and hold the “SELECT” but- ton.
3. Turn the key to “ ”, and then re- lease the “SELECT” button after
five seconds. After that push the
“SELECT” button again. The
brightness screen can now be ad-
justed.
To set the brightness screen1. Push the “RESET” button to select the desired brightness level.
2. Push the “SELECT” button to confirm the selected brightness
screen level. The brightness
screen light changes to the shift
flashing pattern setting mode. To set the shift flashing pattern
1. Push the “RESET” button to select
one of the following flashing pat-
tern settings: On: the indicator light stays
on when activated. (This set-
ting is selected when the indi-
cator light stays on.)
 Flash: the indicator light
flashes when activated. (This
setting is selected when the
indicator light flashes four
times per second.)
 Off: the indicator light is deac-
tivated; in other words, it
does not come on or flash.
(This setting is selected when
the indicator light flashes
once every two seconds.)
2. Push the “SELECT” button to con- firm the selected flashing pattern.
The shift timing indicator light
changes to the activation point
setting mode.
The tachometer will show the current
setting r/min for the activation point
and deactivation point setting modes.
1. Shift timing indicator light
2. Brightness level displayZAUM1580
21
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Instrument and control functions
3-11
3 To set the shift activation point
TIPThe shift timing indicator light activa-
tion point can be set between 9000
r/min and 13000 r/min. The indicator
light can be set in increments of 500
r/min.1. Push the “RESET” button to select
the desired engine speed for acti-
vating the indicator light.
2. Push the “SELECT” button to con- firm the selected engine speed.
The control mode changes to the
deactivation point setting mode.
To set the shift deactivation pointTIP The shift timing indicator light de-
activation point can be set be-
tween 9000 r/min and 13000
r/min. The indicator light can be
set in increments of 500 r/min.
 Be sure to set the deactivation
point to a higher engine speed
than for the activation point, other-
wise the shift timing indicator light
will not come on.
1. Push the “RESET” button to select
the desired engine speed for de-
activating the indicator light.
2. Push the “SELECT” button to con- firm the selected engine speed.
The control mode changes to the
brightness setting mode.
To adjust the shift brightness1. Push the “RESET” button to select the desired shift indicator light
brightness level.
2. Push the “SELECT” button to con- firm the selected brightness level.
The display exits the shift timing
light control mode and returns to
the standard multi-function dis-
play mode.
Welcome screen
The welcome screen greets the rider
when the key is turned to “ ” with the
messages “Hi Buddy” and “see you”
when the key is turned to “ ”. The
user name “Buddy” is set as the facto-
ry default, but it can be set to your
name. 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 process1. Hyphen
2. SpaceZAUM1581
AB C Y Z
012
9
-_
1
2
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Instrument and control functions
3-12
3
for all six characters. After the
sixth character is set, all charac-
ters will flash twice and the setting
mode will automatically end.
Self-d iagnostic device
This model is equipped with a self-di-
agnostic 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 in dicates an error
co de, the vehicle shoul d b e checked
as soon as possi ble in or der to avoi d
en gine damag e.
EAU1234R
Handle bar switchesLeft
Ri ght
1. Self-diagnostic deviceZAUM1582
1
1. Pass switch “ ”
2. Dimmer switch “ / ”
3. Horn switch “ ”
4. Turn signal switch “ / ”
1. Start/Engine stop switch “ / / ”
12
3
4
1
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Instrument and control functions
3-13
3
EAU12352
Pass switch “ ”
Press this switch to flash the headlight.TIPWhen the dimmer switch is set
to “ ”, the passing switch has no ef-
fect.
EAU12402
Dimmer switch “ / ”
Set this switch to “ ” for the high
beam and to “ ” for the low beam.
EAU12461
Turn si gnal switch “ / ”
To signal a right-hand turn, push this
switch to “ ”. To signal a left-hand
turn, push this switch to “ ”. When
released, the switch returns to the cen-
ter position. To cancel the turn signal
lights, push the switch in after it has re-
turned to the center position.
EAU12501
Horn switch “ ”
Press this switch to sound the horn.
EAU68271
Start/En gine stop switch “ / / ”
To crank the engine with the starter,
set this switch to “ ”, and then slide
the switch toward “ ”. See page 5-2
for starting instructions prior to starting
the engine.
Set this switch to “ ” to stop the en-
gine in case of an emergency, such as
when the vehicle overturns or when the
throttle cable is stuck.
EAU12823
Clutch leverTo disengage the drivetrain from the
engine, such as when shifting gears,
pull the clutch lever toward to the han-
dlebar. Release the lever to engage the
clutch and transmit power to the rear
wheel.TIPThe lever should be pulled rapidly and
released slowly for smooth shifting.
(See page 5-3.)1. Clutch lever1
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Instrument and control functions
3-16
3
EAU13077
Fuel tank capTo open the fuel tank cap
Open the fuel tank cap lock cover, in-
sert the key, and then turn it 1/4 turn
clockwise. The lock will be released
and the fuel tank cap can be opened.
To close the fuel tank cap
With the key still inserted, push down
the fuel tank cap. Turn the key 1/4 turn
counterclockwise, remove it, and then
close the lock cover.
TIPThe fuel tank cap cannot be closed un-
less the key is in the lock. In addition,
the key cannot be removed if the cap is
not properly closed and locked.
WARNING
EWA11092
Make sure that the fuel tank cap is
properly close d after fillin g fuel.
Leakin g fuel is a fire hazar d.
EAU13222
FuelMake sure there is sufficient gasoline in
the tank.
WARNING
EWA10882
Gasoline an d gasoline vapors are
extremely flammab le. To avoid fires
an d explosions an d to re duce the
risk of injury when refuelin g, follow
these instructions.1. Before refueling, turn off the en- gine and be sure that no one is sit-
ting on the vehicle. Never refuel
while smoking, or while in the vi-
cinity of sparks, open flames, or
other sources of ignition such as
the pilot lights of water heaters
and clothes dryers.
2. Do not overfill the fuel tank. When refueling, be sure to insert the
pump nozzle into the fuel tank filler
hole. Stop filling when the fuel
reaches the bottom of the filler
tube. Because fuel expands when
it heats up, heat from the engine or
the sun can cause fuel to spill out
of the fuel tank.
1. Fuel tank cap lock cover
2. Unlock.
1
2
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Instrument and control functions
3-17
3
3. Wipe up any spilled fuel immedi-ately. NOTICE: Immediately
wipe off spille d fuel with a clean,
d ry, soft cloth, since fuel may
d eteriorate painted surfaces or
plastic parts.
[ECA10072]
4. Be sure to securely close the fuel tank cap.
WARNING
EWA15152
Gasoline is poisonous an d can
cause injury or death. Han dle gaso-
line with care. Never siphon gasoline
b y mouth. If you shoul d swallow
some gasoline or inhale a lot of gas-
oline vapor, or get some g asoline in
your eyes, see your doctor imme di- ately. If g
asoline spills on your skin,
wash with soap an d water. If gaso-
line spills on your clothin g, chan ge
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.
1. Fuel tank filler tube
2. Maximum fuel level
1
2
Recommended fuel:
Unleaded gasoline (E10 acceptable)
Octane num ber (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)
E5
E10
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Instrument and control functions
3-21
3 this system reg
ularly and have a
Yamaha dealer repair it if it does not
function properly.
EAU44895
I g nition circuit cut-off systemThis 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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