warning YAMAHA YZF-R125 2021 Owner's Manual

Periodic maintenance an d a djustment
6-14
6
EAUS1203
CoolantThe coolant level should be checked
regularly. In addition, the coolant must
be changed at the intervals specified in
the periodic maintenance chart.TIPIf genuine Yamaha coolant is not avail-
able, use an ethylene glycol antifreeze
containing corrosion inhibitors for alu-
minum engines and mix with distilled
water at a 1:1 ratio.
EAUE3460
To check the coolant level
1. Place the vehicle on a level sur- face.
2. Remove cowling C of left side. (See page 6-8.)
3. Hold the vehicle in an upright po- sition.
TIPThe coolant level must be
checked on a cold engine since
the level varies with engine tem-
perature.
 Make sure that the vehicle is posi-
tioned straight up when checking
the coolant level. A slight tilt to the
side can result in a false reading.4. Check the coolant level in the
coolant reservoir.TIPThe coolant should be between the
minimum and maximum level marks.
5. If the coolant is at or below theminimum level mark, remove the
coolant reservoir cap.
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-
stead . Do not use har d water or
salt water since it is harmful to
the en gine. If water has been
use d instead of coolant, replace
it with coolant as soon as possi-
b le, otherwise the coolin g sys-
Recommen ded coolant:
YAMALUBE coolant
Coolant quantity: Coolant reservoir (max level mark):0.15 L (0.16 US qt, 0.13 Imp.qt)
Radiator (including all routes): 0.49 L (0.52 US qt, 0.43 Imp.qt)
1. Coolant reservoir
2. Maximum level mark
3. Minimum level mark
1
2
3
FULL
LOW
ZAUE3384
1. Coolant reservoir cap
1ZAUE3385
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Periodic maintenance an d a djustment
6-15
6
tem will not
be protecte d
a g ainst frost an d corrosion. If
water has been a dded to the
coolant, have a Yamaha dealer
check the antifreeze content of
the coolant as soon as possi ble,
otherwise the effectiveness of
the coolant will be re duce d.
[ECA10473]
7. 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. 2. If dirt or water is visible, remove
the hose, clean it, and then install
it.
Coolant reservoir capacity (up to
the maximum level mark):0.15 L (0.16 US qt, 0.13 Imp.qt)
1. Air filter check hoseZAUM1594
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Periodic maintenance an d a djustment
6-17
6
3. To increase the throttle grip free
play, turn the adjusting nut in di-
rection (a). To decrease the throt-
tle grip free play, turn the adjusting
nut in direction (b).
4. Tighten the locknut and then slide the rubber cover to its original po-
sition.
EAU21403
Valve clearanceThe 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.TIPThis service must be performed when
the engine is cold.
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 be
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 be
a d juste d in accor dance with the
ri din g spee d an d with the total
1. Adjusting nut
2. LocknutZAUM1596
1 2
(a)
(b)
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Periodic maintenance an d a djustment
6-18
6 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.
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 rid ing 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 speed s after
chan gin g a tire since the tire
surface must first be “ broken
in” for it to develop its optimal
characteristics.
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:
Vehicle:
175 kg (387 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 depthMinimum 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
6-19
6
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.
EAU21963
Cast wheelsTo maximize the performance, durabil-
ity, and safe operation of your vehicle,
note the following points regarding the
specified wheels.
 The wheel rims should be
checked for cracks, bends, warp-
age or other damage before each
ride. If any damage is found, have
a Yamaha dealer replace the
wheel. Do not attempt even the
smallest repair to the wheel. A de-
formed or cracked wheel must be
replaced.
 The wheel should be balanced
whenever either the tire or wheel
has been changed or replaced. An
unbalanced wheel can result in
poor performance, adverse han-
dling characteristics, and a short-
ened tire life.
1. Tire air valve
2. Tire air valve core
3. Tire air valve cap with seal
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
6-21
6
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 brake lever free play in-
d icates a hazar dous con dition in the
b rake system. Do not operate the vehicle until the
brake system has
b een checked or repaired by a
Yamaha dealer.
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 ped al free play
in dicates a hazar dous con dition in
the brake system. Do not operate
1. Brake lever free playFront brake lever free play:
2.0–5.0 mm (0.08–0.20 in)ZAUM1599
1
1. Brake pedal free play
Brake pe dal free play:
3.5–4.5 mm (0.14–0.18 in)ZAUM1600
1
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Periodic maintenance an d a djustment
6-23
6
indicator groove has almost disap-
peared, have a Yamaha dealer replace
the brake pads as a set.
EAU36721
Rear
brake pa ds
Each rear brake pad is provided with
wear indicator grooves, which allow
you to check the brake pad wear with-
out having to disassemble the brake.
To check the brake pad wear, check
the wear indicator grooves. If a brake
pad has worn to the point that the wear
indicator grooves have almost disap-
peared, have a Yamaha dealer replace
the brake pads as a set.
EAU40262
Checkin g the brake flui d levelBefore 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 b raking a bility. O bserve
these precautions:  Insufficient brake flui d may al-
low air to enter the b rake sys-
tem, re ducing brakin g
performance.
 Clean the filler cap before re-
moving . Use only DOT 4 b rake
flui d from a seale d container.
1. Wear indicator grooveZAUM1601
1
1
1. Minimum level mark
1
ZAUM1057
1. Minimum level mark
Specified b rake flui d:
DOT 4ZAUM1603
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Periodic maintenance an d a djustment
6-27
6
EAU23098
Checkin g an d lu bricatin g the
ca blesThe 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 ca ble 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.
EAU44276
Checkin g an d lu bricatin g the
b rake an d shift pe dalsThe operation of the brake and shift
pedals should be checked before each
ride, and the pedal pivots should be lu-
bricated if necessary.
Brake pe dal
Shift pe dal
Recommen ded lu bricant:
Yamaha cable lubricant or other
suitable cable lubricant
ZAUM1606ZAUM1607
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Periodic maintenance an d a djustment
6-29
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 sid estand 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
Lu bricatin 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.
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.
Recommen ded lu bricant:
Lithium-soap-based greaseZAUM1620
Recommen ded lu bricant:
Lithium-soap-based grease
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Periodic maintenance an d a djustment
6-30
6
NOTICE
ECA10591
If any d amage 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.
EAU23292
Checkin g the wheel bearin gsThe 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.
ZAUM1187
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