warning YAMAHA MT-125 2021 Owner's Manual

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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Periodic maintenance an d a djustment
6-21
6
EAUM1355
A djustin g the brake pe dal free
playMeasure the brake pedal free play as
shown.
Periodically check the brake pedal free
play and, if necessary, have a Yamaha
dealer adjust it.
WARNING
EWAM1031
An incorrect brake pe dal free play
in dicates a hazar dous con dition in
the brake system. Do not operate the motorcycle until the
brake sys-
tem has b een checked or repaired
b y a Yamaha dealer.
EAU36505
Brake li ght switchesThe brake light should come on just
before braking takes effect. The brake
light is activated by switches connect-
ed to the brake lever and brake pedal.
Since the brake light switches are
components of the anti-lock brake sys-
tem, they should only be serviced by a
Yamaha dealer.
1. Brake pedal free playBrake pe dal free play:
7.0–13.0 mm (0.28–0.51 in)
1
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Periodic maintenance an d a djustment
6-23
6
Rear
brake
WARNING
EWA16011
Improper maintenance can result in
loss of b raking a bility. O bserve
these precautions:  Insufficient brake flui d may al-
low air to enter the brake sys-
tem, re ducin g brakin g
performance.
 Clean the filler cap before re-
movin g. Use only DOT 4 brake
flui d from a seale d container. 
Use only the specified b rake flu-
i d ; otherwise, the ru bber seals
may deteriorate, causin g leak-
a g e.
 Refill with the same type of
brake flui d. A dding a brake fluid
other than DOT 4 may result in a
harmful chemical reaction.
 Be careful that water or d ust
d oes not enter the brake flui d
reservoir when refillin g. Water
will si gnificantly lower the boil-
in g point of the flui d an d may re-
sult in vapor lock, an d d ir
t may
clo g the ABS hy draulic unit
valves.
NOTICE
ECA17641
Brake flui d may d amage painte d
surfaces or plastic parts. Always
clean up spilled fluid imme diately.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 markSpecifie
d b rake flui d:
DOT 4
1
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Periodic maintenance an d a djustment
6-26
6 may contain su
bstances that
coul d damag e the O-rin gs.
[ECA11112] EAU23098
Checkin
g an d lu bricatin g the
cab lesThe operation of all control cables and
the condition of the cables should be
checked before each ride, and the ca-
bles and cable ends should be lubri-
cated if necessary. If a cable is
damaged or does not move smoothly,
have a Yamaha dealer check or re-
place it. WARNING! Dama ge to the
outer housin g of cab les may result
in internal rustin g an d cause inter-
ference with cab le movement. Re-
place damag ed cab les as soon as
possi ble to prevent unsafe con di-
tions.
[EWA10712] EAU23115
Checkin
g an d lu bricatin g the
throttle grip an d ca bleThe operation of the throttle grip
should be checked before each ride. In
addition, the cable should be lubricat-
ed by a Yamaha dealer at the intervals
specified in the periodic maintenance
chart.
The throttle cable is equipped with a
rubber cover. Make sure that the cover
is securely installed. Even though the
cover is installed correctly, it does not
completely protect the cable from wa-
ter entry. Therefore, use care not to
pour water directly onto the cover or
cable when washing the vehicle. If the
cable or cover becomes dirty, wipe
clean with a moist cloth.
Recommen ded lu bricant:
Yamaha cable lubricant or other
suitable cable lubricant
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Periodic maintenance an d a djustment
6-28
6
EAU23203
Checkin g an d lu bricatin g the
si destan dThe operation of the sidestand should
be checked before each ride, and the
sidestand pivot and metal-to-metal
contact surfaces should be lubricated
if necessary.
WARNING
EWA10732
If the si destan d d oes not move up
an d d own smoothly, have a Yamaha
d ealer check or repair it. Otherwise,
the si destan d coul d contact the
g roun d an d d istract the operator, re-
sultin g in a possi ble loss of control.
EAU23252
Lub ricatin g the rear suspen-
sionThe pivoting points of the rear suspen-
sion must be lubricated by a Yamaha
dealer at the intervals specified in the
periodic maintenance and lubrication
chart.
Recommen ded lu bricants:
Brake lever:
Silicone grease
Clutch lever:
Lithium-soap-based grease
Recommen ded lu bricant:
Lithium-soap-based grease
Recommen ded lu bricant:
Lithium-soap-based grease
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Periodic maintenance an d a djustment
6-29
6
EAU23273
Checkin g the front forkThe condition and operation of the
front fork must be checked as follows
at the intervals specified in the periodic
maintenance and lubrication chart.
To check the con dition
Check the inner tubes for scratches,
damage and excessive oil leakage.
To check the operation 1. Place the vehicle on a level sur- face and hold it in an upright posi-
tion. WARNING! To avoi d injury,
securely support the vehicle so
there is no dan ger of it fallin g
over.
[EWA10752]
2. While applying the front brake, push down hard on the handle-
bars several times to check if the
front fork compresses and re-
bounds smoothly.
NOTICE
ECA10591
If any damag e is foun d or the front
fork does not operate smoothly,
have a Yamaha d ealer check or re-
pair it.
EAU23285
Checkin g the steerin gWorn or loose steering bearings may
cause danger. Therefore, the operation
of the steering must be checked as fol-
lows at the intervals specified in the
periodic maintenance and lubrication
chart.
1. Raise the front wheel off the ground. (See page 6-34.)
WARNING! To avoi d injury, se-
curely support the vehicle so
there is no dan ger of it fallin g
over.
[EWA10752]
2. Hold the lower ends of the front fork legs and try to move them for-
ward and backward. If any free
play can be felt, have a Yamaha
dealer check or repair the steer-
ing.ZAUM1744
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Periodic maintenance an d a djustment
6-30
6
EAU23292
Checkin g the wheel b earingsThe front and rear wheel bearings must
be checked at the intervals specified in
the periodic maintenance and lubrica-
tion chart. If there is play in the wheel
hub or if the wheel does not turn
smoothly, have a Yamaha dealer
check the wheel bearings.
EAU50583
BatteryThe battery is located under the rider
seat. It is a VRLA (valve-regulated lead-
acid) battery. There is no need to check
the electrolyte or to add distilled water.
However, the battery lead connections
need to be checked, and tightened if
necessary.
WARNING
EWA10761
 Electrolyte is poisonous an d
d an gerous since it contains sul-
furic aci d, which causes severe
b urns. Avoi d any contact with
skin, eyes or clothin g an d al- ways shiel
d your eyes when
workin g near b atteries. In case
of contact, ad minister the fol-
lowin g FIRST AID.
EXTERNAL: Flush with plenty of water.
INTERNAL: Drink lar ge quan-
tities of water or milk an d im-
me diately call a physician.
EYES: Flush with water for 15 minutes an d seek prompt
me dical attention.
 Batteries pro duce explosive hy-
d ro gen gas. Therefore, keep
sparks, flames, ci garettes, etc.,
away from the battery an d pro-
vi de sufficient ventilation when
char gin g it in an enclose d
space.
 KEEP THIS AND ALL BATTER-
IES OUT OF THE REACH OF
CHILDREN.
NOTICE
ECA10621
Never attempt to remove the b attery
cell seals, as this would permanently
d amag e the battery.
1. Positive battery lead (red)
2. Battery
3. Negative battery lead (black)
1
2
3
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