2021 YAMAHA MT-125 warning

Operation and important ri din g points
5-1
5
EAU15952
Read the Owner’s Manual carefully to
become familiar with all controls. If
there is a control or function you do not
understand, ask your Yamaha dealer.
WARNING
EWA10272
Failure to familiarize yourself with
the controls can lead to loss of con-
trol, which coul d cause an acci dent
or injury.
EAU16831
En gine break-inThere is never a more important period
in the life of your engine than the period
between 0 and 1000 km (600 mi). For
this reason, you should read the fol-
lowing material carefully.
Since the engine is brand new, do not
put an excessive load on it for the first
1000 km (600 mi). The various parts in
the engine wear and polish themselves
to the correct operating clearances.
During this period, prolonged full-throt-
tle operation or any condition that
might result in engine overheating
must be avoided.
EAU16983
0–500 km (0–300 mi)
Avoid prolonged operation above 5000
r/min.
After every hour of operation, stop the
engine, and then let it cool for five to
ten minutes.
Vary the engine speed from time to
time. Do not operate the engine at one
set throttle position. 500–1000 km (300–600 mi)
Avoid prolonged operation above 7500
r/min.
Rev the engine freely through the
gears, but do not use full throttle at any
time.
NOTICE: After 1000 km (600 mi)
of operation, the en gine oil must b e
chan ged , the oil filter cartri dge or el-
ement replace d, an d the oil strainer
cleaned .
[ECA10322]
1000 km (600 mi) and b eyon d
The vehicle can now be operated nor-
mally.NOTICE
ECA10311
 Keep the en gine spee d out of
the tachometer red zone.
 If any en gine trou ble shoul d oc-
cur during the en gine break-in
perio d, imme diately have a
Yamaha dealer check the vehi-
cle.
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Operation and important rid ing points
5-2
5
EAU86690
Startin g the eng ineThe ignition circuit cut-off system will
enable starting when:
 the transmission is in the neutral
position or
 the transmission is in gear, the
sidestand is up, and the clutch le-
ver is pulled.
To start the engine1. Turn the main switch on and set the engine stop switch to the run
position.
2. Confirm the indicator and warning light(s) come on for a few sec-
onds, and the go off. (See page
3-2.)TIPDo not start the engine if the en-
gine trouble warning light remains
on.
 The ABS warning light should
come on and stay on until the ve-
hicle reaches a speed of 10 km/h
(6 mi/h).
NOTICE
ECA24110
If a warnin g or in dicator li ght does
not work as d escribed a bove, have a
Yamaha dealer check the vehicle.3. Shift the transmission into the
neutral position.
4. Start the engine by pushing the start switch.
5. Release the start switch when the engine starts, or after 5 seconds.
Wait 10 seconds before pressing
the switch again to allow battery
voltage to restore.NOTICE
ECA11043
For maximum en gine life, never ac-
celerate har d when the en gine is
col d!
EAU45312
TIPThis model is equipped with a lean an-
gle sensor to stop the engine in case of
a turnover. In this case, turn the main
switch off and then on. Failing to do so
will prevent the engine from starting
even though the engine will crank
when pushing the start switch.
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Operation and important rid ing points
5-4
5 The neutral indicator light should
come on and then the clutch lever
can be released.
WARNING
EWA17380

Improper brakin g can cause
loss of control or traction. Al-
ways use b oth brakes an d apply
them smoothly.
 Make sure that the motorcycle
and the en gine have sufficiently
slowe d b efore shiftin g to a low-
er gear. En gag in g a lower gear
when the vehicle or en gine
speed is too hi gh coul d make
the rear wheel lose traction or
the en gine to over-rev. This
coul d cause loss of control, an
acci dent an d injury. It coul d also
cause en gine or drive train dam-
a g e.
EAU16811
Tips for re ducin g fuel con-
sumptionFuel consumption depends largely on
your riding style. Consider the follow-
ing tips to reduce fuel consumption:
 Shift up swiftly, and avoid high en-
gine speeds during acceleration.
 Do not rev the engine while shift-
ing down, and avoid high engine
speeds with no load on the en-
gine.
 Turn the engine off instead of let-
ting it idle for an extended length
of time (e.g., in traffic jams, at traf-
fic lights or at railroad crossings).
EAU17214
Parkin gWhen parking, stop the engine, and
then remove the key from the main
switch.
WARNING
EWA10312
Since the en gine an d exhaust
system can become very hot,
park in a place where pe destri-
ans or chil dren are not likely to
touch them an d b e burne d.
 Do not park on a slope or on soft
groun d, otherwise the vehicle
may overturn, increasin g the
risk of a fuel leak an d fire.
 Do not park near grass or other
flammab le materials which
mi ght catch fire.
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Periodic maintenance an d a djustment
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 performin g maintenance ac-
tivities incorrectly may increase
your risk of injury or death during
service or while usin g the vehicle. If
you are not familiar with vehicle ser-
vice, have a Yamaha d ealer perform
service.
WARNING
EWA15123
Turn off the en gine when performin g
maintenance unless otherwise
specified .
 A runnin g en gine has movin g
parts that can catch on b ody
parts or clothin g an d electrical
parts that can cause shocks or
fires.
 Runnin g the eng ine while ser-
vicin g can lead to eye injury,
b urns, fire, or car bon monoxi de
poisonin g – possi bly lea din g to
d eath. See pag e 1-3 for more in-
formation a bout car bon monox-
i d e.
WARNING
EWA15461
Brake discs, calipers, drums, an d
linin gs can b ecome very hot during
use. To avoi d possi ble burns, let
b rake components cool before
touching them.
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.
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Periodic maintenance an d a djustment
6-14
6 6. Add coolant to the maximum level
mark, and then install the coolant
reservoir cap. WARNING! Re-
move only the coolant reservoir
cap. Never attempt to remove
the ra diator cap when the en-
g ine is hot.
[EWA15162]
NOTICE: If
coolant is not availa ble, use dis-
tille d water or soft tap water in-
stea d. Do not use har d water or
salt water since it is harmful to
the en gine. If water has been
use d instea d of coolant, replace
it with coolant as soon as possi-
b le, otherwise the coolin g sys-
tem will not be protected
a g ainst frost an d corrosion. If
water has b een added to the
coolant, have a Yamaha d ealer
check the antifreeze content of
the coolant as soon as possi ble,
otherwise the effectiveness of
the coolant will b e reduced.
[ECA10473]
7. Install the coolant reservoir cap
protector.
8. Install the cowling.
EAU33032
Chan gin g the coolant
The coolant must be changed at the in-
tervals specified in the periodic main-
tenance and lubrication chart. Have a
Yamaha dealer change the coolant.
WARNING! Never attempt to remove the ra diator cap when the en gine is
hot.
[EWA10382] EAUM2391
Replacin
g the air filter ele-
ment an d cleanin g the check
hoseThe air filter element should be re-
placed at the intervals specified in the
periodic maintenance and lubrication
chart. Have a Yamaha dealer replace
the air filter element more frequently if
you are riding in unusually wet or dusty
areas. In addition, the air filter check
hose must be frequently checked and
cleaned if necessary.
To clean the air filter check hose
1. Check the hose on the side of the air filter case for accumulated dirt
or water.
Coolant reservoir capacity (up to
the maximum level mark):0.15 L (0.16 US qt, 0.13 Imp.qt)
1. Air filter check hoseZAUM1739
1
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Periodic maintenance an d a djustment
6-17
6
EAU77621
TiresTires 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 d eath from loss of
control.  The tire air pressure must b e
checked and a djuste d on col d
tires (i.e., when the temperature
of the tires equals the am bient
temperature).
 The tire air pressure must b e
a d juste d in accor dance with the
ri din g speed and with the total wei
ght of ri der, passen ger, car-
g o, an d accessories approve d
for this mo del.
WARNING
EWA10512
Never overloa d your vehicle. Opera-
tion of an overloa ded vehicle coul d
cause an acci dent.
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.TIPThe tire tread depth limits may differ
from country to country. Always com-
ply with the local regulations.
Col d 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 loa d:
Veh ic le:
178 kg (392 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 trea d d epth (front an d
rear): 1.6 mm (0.06 in)
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Periodic maintenance an d a djustment
6-18
6
WARNING
EWA10472
 Have a Yamaha dealer replace
excessively worn tires. Besi des
b ein g ille gal, operatin g the vehi-
cle with excessively worn tires
d ecreases ri din g sta bility an d
can lead to loss of control.
 The replacement of all wheel
and b rake-relate d parts, inclu d-
in g the tires, shoul d b e left to a
Yamaha dealer, who has the
necessary professional knowl-
e dge an d experience to do so.
 Ride at mo derate spee ds after
chan gin g a tire since the tire
surface must first be “ broken
in” for it to develop its optimal
characteristics.
Tire information
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 an d rear tires shoul d
b e of the same make an d d e-
si gn, otherwise the han dlin g characteristics of the vehicle
may
be different, which coul d
lea d to an acci dent.
 Always make sure that the valve
caps are securely installe d to
prevent air pressure leaka ge.
 Use only the tire valves an d
valve cores liste d below to
avoi d tire d eflation during a ride.
After extensive tests, only the tires list-
ed below have been approved for this
model by Yamaha.
1. Tire air valve
2. Tire air valve core
3. Tire air valve cap with seal
12 3
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 an d a djustment
6-20
6 6. To increase the clutch lever free
play, turn the clutch lever free play
adjusting nut in direction (a). To
decrease the clutch lever free
play, turn the adjusting nut in di-
rection (b).
7. Tighten the locknut at the crank- case.
8. Tighten the locknut at the clutch lever and then slide the rubber
cover to its original position.
EAUT1223
Checkin g the front b rake lever
free playMeasure the front brake lever free play
as shown.
Periodically check the brake lever free
play and, if necessary, have a Yamaha
dealer check the brake system.
WARNING
EWA10642
An incorrect b rake lever free play in-
d icates a hazar dous con dition in the
b rake system. Do not operate the vehicle until the b
rake system has
b een checked or repaired by a
Yamaha dealer.1. Brake lever free playFront brake lever free play:
2.0–5.0 mm (0.08–0.20 in)
1
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