2021 YAMAHA YZF-R125 lock

Instrument and control functions
3-7
3 1” and “TRIP 2”, instantaneous fuel
consumption mode “km/L” or “L/100
km”, average fuel consumption mode
“AVE_ _._ km/L” or “AVE_ _._ L/100
km” and average speed mode “AVE_
_._ km/h” in the following order:
ODO
→ TRIP 1 → TRIP 2 → km/L or
L/100 km → AVE_ _._ km/L or AVE_ _._
L/100 km → AVE_ _._ km/h → ODO
For the UK:
Push the “SELECT” button to switch
the display between the odometer
mode “ODO”, tripmeters mode “TRIP
1” and “TRIP 2”, instantaneous fuel
consumption mode “km/L” or “L/100
km” or “MPG”, average fuel consump-
tion mode “AVE_ _._ km/L”, “AVE_ _._
L/100 km” or “AVE_ _ _._ MPG” and
average speed mode “AVE_ _._ km/h”
or “AVE_ _._ MPH” in the following or-
der:
ODO → TRIP 1 → TRIP 2 → km/L or
L/100 km or MPG → AVE_ _._ km/L or
AVE_ _._ L/100 km or AVE_ _ _._
MPG → AVE_ _._ km/h or AVE_ _._
MPH → ODO Push the “RESET” button to switch
display backward.
If the last segment of the fuel meter
starts flashing, the display automati-
cally changes to the fuel reserve trip-
meter mode “TRIP F” and starts
counting the distance traveled from
that point. In that case, push the “SE-
LECT” button to switch the display be-
tween the various tripmeter, odometer,
instantaneous fuel consumption, aver-
age fuel consumption, and average
speed modes in the following order:
TRIP F
→ km/L or L/100 km → AVE_
_._ km/L or AVE_ _._ L/100 km → AVE_
_._ km/h → ODO → TRIP 1 → TRIP 2
→ TRIP F
For the UK:
TRIP F → km/L, L/100 km or MPG →
AVE_ _._ km/L, AVE_ _._ L/100 km or
AVE_ _ _._ MPG → AVE_ _._ km/h or
AVE_ _._ MPH → ODO → TRIP 1 →
TRIP 2 → TRIP F To reset a tripmeter, select it by push-
ing the “SELECT” button and then
push and hold the “RESET” button.
If you do not reset the fuel reserve trip-
meter manually, it resets itself auto-
matically and the display returns to the
prior mode after refueling and traveling
5 km (3 mi).
O
dometer mo de
The odometer shows the total distance
traveled by the vehicle. It will lock at
999999 and cannot be reset.
1. OdometerZAUM1575
1
UB5GE2E0.book Page 7 Thursday, July 30, 2020 3:08 PM

Instrument and control functions
3-15
3
EAU63040
ABSThe Yamaha ABS (Anti-lock Brake
System) features a dual electronic con-
trol system, which acts on the front and
rear brakes independently.
Operate the brakes with ABS as you
would conventional brakes. If the ABS
is activated, a pulsating sensation may
be felt at the brake lever or brake ped-
al. In this situation, continue to apply
the brakes and let the ABS work; do
not “pump” the brakes as this will re-
duce braking effectiveness.
WARNING
EWA16051
Always keep a sufficient d istance
from the vehicle ahea d to match the
ri din g speed even with ABS.
 The ABS performs best with
lon g b rakin g d istances.
 On certain surfaces, such as
rou gh or g ravel roa ds, the b rak-
in g d istance may b e longer with
the ABS than without.The ABS is monitored by an ECU,
which will revert the system to conven-
tional braking if a malfunction occurs.
TIP The ABS performs a self-diagno-
sis test each time the vehicle first
starts off after the key is turned to
“ON” and the vehicle has traveled
at a speed of 10 km/h (6 mi/h) or
higher. During this test, a “click-
ing” noise can be heard from the
hydraulic control unit, and if the
brake lever or brake pedal is even
slightly applied, a vibration can be
felt at the lever and pedal, but
these do not indicate a malfunc-
tion.
 This ABS has a test mode which
allows the owner to experience
the pulsation at the brake lever or
brake pedal when the ABS is op-
erating. However, special tools are
required, so please consult your
Yamaha dealer.NOTICE
ECA20100
Be careful not to damag e the wheel
sensor or wheel sensor rotor; other-
wise, improper performance of the
ABS will result.
1. Front wheel sensor rotor
2. Front wheel sensor
1. Rear wheel sensor
2. Rear wheel sensor rotorZAUM158912ZAUM1590
12
UB5GE2E0.book Page 15 Thursday, July 30, 2020 3:08 PM

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.ZAUM1591
2 1
UB5GE2E0.book Page 16 Thursday, July 30, 2020 3:08 PM

Instrument and control functions
3-18
3
NOTICE
ECA11401
Use only unlea ded g asoline. The use
of lead ed g asoline will cause severe
d amag e to internal en gine parts,
such as the valves an d piston rin gs,
as well as to the exhaust system.
EAU86240
Fuel tank breather hose an d
overflow hoseThe breather hose prevents a vacuum
condition from forming within the fuel
tank.
The overflow hose drains excess gaso-
line and directs it safely away from the
vehicle.
Before operating the vehicle:
 Check each hose connection.
 Check each hose for cracks or
damage, and replace if necessary.
 Make sure that the end of each
hose is not blocked, and clean if
necessary. 
Make sure that each hose is posi-
tioned as shown.1. Guide
2. Fuel tank overflow hose
3. Canister breather hoseZAUM1801
1
32
UB5GE2E0.book Page 18 Thursday, July 30, 2020 3:08 PM

Instrument and control functions
3-20
3
2. Install the passenger seat by in-
stalling and tightening the nut to
the specified torque.
3. Install the plastic cover.
Ri der seat
To remove the rider seat
1. Insert the key into the seat lock, and then turn it clockwise.
2. While holding the key in the posi- tion “2”, lift from rear of the rider
seat and pull it backward. To install the rider seat
1. Insert the projection on the front of
the rider seat into the seat holder
as shown, place the seat in the
original position.
2. Remove the key.TIPMake sure that the seats are properly
secured before riding.
EAU15306
Si destan dThe sidestand is located on the left
side of the frame. Raise the sidestand
or lower it with your foot while holding
the vehicle upright.TIPThe built-in sidestand switch is part of
the ignition circuit cut-off system,
which cuts the ignition in certain situa-
tions. (See the following section for an
explanation of the ignition circuit cut-
off system.)
WARNING
EWA10242
The vehicle must not be ri dden with
the si destan d d own, or if the si de-
stan d cannot b e properly move d up
(or does not stay up), otherwise the
si destan d coul d contact the groun d
an d d istract the operator, resultin g
in a possib le loss of control.
Yamaha’s ig nition circuit cut-off
system has been desi gne d to assist
the operator in fulfillin g the respon-
si bility of raisin g the sid estand b e-
fore startin g off. Therefore, check
Ti ghtenin g torque:
Passenger seat nut: 13 N·m (1.3 kgf·m, 9.6 lb·ft)1. Rider seat lock
2. Unlock.
21
ZAUE3366
1. Projection
2. Seat holder
21
ZAUE3367
UB5GE2E0.book Page 20 Thursday, July 30, 2020 3:08 PM

Periodic maintenance an d a djustment
6-10
6 Before installing a spark plug, the
spark plug gap should be measured
with a wire thickness gauge and, if
necessary, adjusted to specification.
Clean the surface of the spark plug
gasket and its mating surface, and
then wipe off any grime from the spark
plug threads.
TIPIf a torque wrench is not available
when installing a spark plug, a good
estimate of the correct torque is 1/4–
1/2 turn past finger tight. However, the
spark plug should be tightened to the
specified torque as soon as possible.
EAU36112
CanisterThis model is equipped with a canister
to prevent the discharging of fuel vapor
into the atmosphere. Before operating
this vehicle, make sure to check the
following:
 Check each hose connection.
 Check each hose and canister for
cracks or damage. Replace if
damaged.
 Make sure that the canister
breather is not blocked, and if
necessary, clean it.
1. Spark plug gapSpark plu g g ap:
0.8–0.9 mm (0.031–0.035 in)
Ti ghtenin g torque:
Spark plug: 12.5 N·m (1.25 kgf·m, 9.22 lb·ft)
1
ZAUM0037
UB5GE2E0.book Page 10 Thursday, July 30, 2020 3:08 PM

Periodic maintenance an d a djustment
6-16
6
EAU34302
A djustin g the eng ine idlin g
spee dThe engine idling speed must be
checked and, if necessary, adjusted as
follows at the intervals specified in the
periodic maintenance and lubrication
chart.
The engine should be warm before
making this adjustment.
Check the engine idling speed and, if
necessary, adjust it to specification by
turning the idle adjusting screw. To in-
crease the engine idling speed, turn
the screw in direction (a). To decrease
the engine idling speed, turn the screw
in direction (b).
TIPIf the specified idling speed cannot be
obtained as described above, have a
Yamaha dealer make the adjustment.
EAU48434
A djustin g the throttle grip free
playMeasure the throttle grip free play as
shown.
Periodically check the throttle grip free
play and, if necessary, adjust it as fol-
lows.TIPThe engine idling speed must be cor-
rectly adjusted before checking and
adjusting the throttle grip free play.1. Slide the rubber cover back.
2. Loosen the locknut.
1. Idle adjusting screwZAUE3388
(a)
(b)
1
En gine i dlin g spee d:
1250–1550 r/min
1. Throttle grip free playThrottle grip free play:
3.0–5.0 mm (0.12–0.20 in)ZAUM1595
1
UB5GE2E0.book Page 16 Thursday, July 30, 2020 3:08 PM

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)
UB5GE2E0.book Page 17 Thursday, July 30, 2020 3:08 PM