2021 YAMAHA YZF-R125 warning light

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
6-14
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
UB5GE2E0.book Page 14 Thursday, July 30, 2020 3:08 PM

Motorcycle care and stora ge
7-2
7
chemicals such as, solvents,
g
asoline, rust removers, b rake
flui d, or antifreeze, etc.
Before washin g
1. Park the vehicle out of direct sun- light and allow it to cool. This will
help avoid water spots.
2. Make sure all caps, covers, elec- trical couplers and connectors are
tightly installed.
3. Cover the muffler end with a plas- tic bag and a strong rubber band.
4. Pre-soak stubborn stains like in- sects or bird droppings with a wet
towel for a few minutes.
5. Remove road grime and oil stains with a quality degreasing agent
and a plastic-bristle brush or
sponge. NOTICE: Do not use
d eg reasin g a gent on areas re-
quirin g lu brication such as
seals, gaskets, an d wheel axles.
Follow pro duct instructions.
[ECA26290]
Washin g
1. Rinse off any degreaser and spray down the vehicle with a garden
hose. Use only enough pressure
to do the job. Avoid spraying wa-
ter directly into the muffler, instru-
ment panel, air inlet, or other inner
areas such as underseat storage
compartments.
2. Wash the vehicle with a quality au- tomotive-type detergent mixed
with cool water and a soft, clean
towel or sponge. Use an old tooth-
brush or plastic-bristle brush for
hard-to-reach places. NOTICE:
Use col d water if the vehicle has
b een exposed to salt. Warm wa-
ter will increase salt’s corrosive
properties.
[ECA26301]
3. For windshield-equipped vehicles: Clean the windshield with a soft
towel or sponge dampened with
water and a pH neutral detergent.
If necessary, use a high-quality
windshield cleaner or polish for
motorcycles. NOTICE: Never use
any stron g chemicals to clean
the wind shield. Additionally,
some cleanin g compoun ds for plastic may scratch the win
d-
shiel d, so b e sure to test all
cleanin g pro ducts before gen-
eral application.
[ECA26310]
4. Rinse off thoroughly with clean water. Be sure to remove all deter-
gent residues, as they can be
harmful to plastic parts.
After washin g
1. Dry the vehicle with a chamois or absorbent towel, preferably mi-
crofiber terrycloth.
2. For drive chain-equipped models: Dry and then lubricate the drive
chain to prevent rust.
3. Use a chrome polish to shine chrome, aluminum, and stainless
steel parts. Often the thermally in-
duced discoloring of stainless
steel exhaust systems can be re-
moved through polishing.
4. Apply a corrosion protection spray on all metal parts including
chrome or nickel-plated surfaces.
WARNING! Do not apply sili- cone or oil spray to seats, han d
g rips, ru bber foot pe gs or tire
trea ds. Otherwise these parts
UB5GE2E0.book Page 2 Thursday, July 30, 2020 3:08 PM

Motorcycle care and stora ge
7-3
7 will
become slippery, which
coul d cause loss of control.
Thorou ghly clean the surfaces
of these parts before operatin g
the vehicle.
[EWA20650]
5. Treat rubber, vinyl, and unpainted plastic parts with a suitable care
product.
6. Touch up minor paint damage caused by stones, etc.
7. Wax all painted surfaces using a non-abrasive wax or use a detail
spray for motorcycles.
8. When finished cleaning, start the engine and let it idle for several
minutes to help dry any remaining
moisture.
9. If the headlight lens has fogged up, start the engine and turn on
the headlight to help remove the
moisture.
10. Let the vehicle dry completely be- fore storing or covering it.NOTICE
ECA26320
Do not apply wax to ru bber or
unpainte d plastic parts. 
Do not use a brasive polishin g
compoun ds as they will wear
away the paint.
 Apply sprays an d wax sparin gly.
Wipe off excess afterwar ds.
WARNING
EWA20660
Contaminants left on the b rakes or
tires can cause loss of control.  Make sure there is no lu bricant
or wax on the brakes or tires.
 If necessary, wash the tires with
warm water an d a mil d d eter-
g ent.
 If necessary, clean the brake
d iscs an d pa ds with brake
cleaner or acetone.
 Before ri din g at hi gher spee ds,
test the vehicle’s b raking per-
formance an d cornerin g b ehav-
ior.
EAU83472
Stora geAlways store the vehicle in a cool, dry
place. If necessary, protect it against
dust with a porous cover. Be sure the
engine and the exhaust system are
cool before covering the vehicle. If the
vehicle often sits for weeks at a time
between uses, the use of a quality fuel
stabilizer is recommended after each
fill-up.NOTICE
ECA21170
 Storin g the vehicle in a poorly
ventilate d room or coverin g it
with a tarp, while it is still wet,
will allow water an d humi dity to
seep in an d cause rust.
 To prevent corrosion, avoi d
d amp cellars, sta bles (b ecause
of the presence of ammonia)
an d areas where stron g chemi-
cals are store d.Lon g term stora ge
Before storing the vehicle long term (60
days or more):
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10-1
10
Index
AABS....................................................... 3-15
ABS warning light ................................... 3-3
Air filter element and check hose,
replacing and cleaning ....................... 6-15BBattery .................................................. 6-31
Brake and clutch levers, checking and lubricating........................................... 6-28
Brake and shift pedals, checking and lubricating........................................... 6-27
Brake fluid, changing............................ 6-24
Brake fluid level, checking.................... 6-23
Brake lever............................................ 3-14
Brake light switches ............................. 6-22
Brake pedal .......................................... 3-14
Brake pedal free play, adjusting ........... 6-21CCables, checking and lubricating ......... 6-27
Canister ................................................ 6-10
Care ........................................................ 7-1
Catalytic converter ............................... 3-19
Clutch lever........................................... 3-13
Clutch lever free play, adjusting ........... 6-20
Coolant ................................................. 6-14
Coolant temperature warning light ......... 3-2
Cowlings, removing and installing.......... 6-8DData recording, vehicle........................... 9-2
Diagnostic connector ............................. 9-2
Dimmer/Pass switch............................. 3-13
Drive chain, cleaning and lubricating ... 6-26
Drive chain slack .................................. 6-25
EEngine break-in ...................................... 5-1
Engine idling speed.............................. 6-16
Engine oil and oil filter element ............ 6-11
Engine overheating .............................. 6-37
Engine serial number ............................. 9-1
Engine stop switch............................... 3-13FFront and rear brake pads, checking ... 6-22
Front brake lever free play, checking ... 6-21
Front fork, checking ............................. 6-29
Fuel ...................................................... 3-16
Fuel consumption, tips for reducing ...... 5-4
Fuel tank breather hose and overflow hose ................................................... 3-18
Fuel tank cap........................................ 3-16
Fuses, replacing ................................... 6-32HHandlebar switches ............................. 3-12
High beam indicator light ....................... 3-2
Horn switch .......................................... 3-13IIdentification numbers ........................... 9-1
Ignition circuit cut-off system .............. 3-21
Indicator lights and warning lights ......... 3-2LLicense plate light bulb, replacing ....... 6-34MMain switch/steering lock ...................... 3-1
Maintenance and lubrication, periodic... 6-4
Maintenance, emission control system ................................................. 6-3
Malfunction indicator light (MIL)............. 3-3
Matte color, caution ............................... 7-1 Model label ............................................. 9-1
Multi-function meter unit ........................ 3-4
NNeutral indicator light ............................. 3-2PParking.................................................... 5-4
Part locations.......................................... 2-1RRear suspension, lubricating ................ 6-29SSafety information................................... 1-1
Seats ..................................................... 3-19
Shifting.................................................... 5-3
Shift light ................................................. 3-3
Shift pedal............................................. 3-14
Sidestand.............................................. 3-20
Sidestand, checking and lubricating .... 6-29
Spark plug, checking .............................. 6-9
Specifications ......................................... 8-1
Starting the engine ................................. 5-2
Start switch ........................................... 3-13
Steering, checking ................................ 6-30
Storage ................................................... 7-3
Supporting the motorcycle ................... 6-34TTail/brake light ...................................... 6-33
Throttle grip and cable, checking and
lubricating ........................................... 6-27
Throttle grip free play, adjusting ........... 6-16
Tires ...................................................... 6-17
Tool kit .................................................... 6-2
Troubleshooting .................................... 6-35
Troubleshooting chart........................... 6-36
Turn signal indicator light ....................... 3-2
UB5GE2E0.book Page 1 Thursday, July 30, 2020 3:08 PM