lock YAMAHA XSR 125 2021 User Guide

Instrument and control functions
3-15
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 hoseZAUM2032
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Instrument and control functions
3-16
3
EAU13435
Catalytic converterThe exhaust system contains catalytic
converter(s) to reduce harmful exhaust
emissions.
WARNING
EWA10863
The exhaust system is hot after op-
eration. To prevent a fire hazar d or
b urns:
 Do not park the vehicle near
possi ble fire hazar ds such as
g rass or other materials that
easily burn.
 Park the vehicle in a place
where pe destrians or chil dren
are not likely to touch the hot
exhaust system.
 Make sure that the exhaust sys-
tem has coole d down before
d oin g any maintenance work.
 Do not allow the en gine to i dle
more than a few minutes. Lon g
i d lin g can cause a buil d-up of
heat.
EAU13941
SeatTo remove the seat 1. Insert the key into the seat lock, and then turn it clockwise.
2. While holding the key in that posi- tion, lift the rear of the seat, and
then pull the seat off.
To install the seat 1. Insert the projection on the front of the seat into the seat holder as
shown. 2. Push the rear of the seat down to
lock it in place.
3. Remove the key.
TIPMake sure that the seat is properly se-
cured before riding.
1. Seat lock
2. Turn.
2
1
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Periodic maintenance an d a djustment
6-9
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.
EAU36113
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
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Periodic maintenance an d a djustment
6-15
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 screw
1
(b)
(a)
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)
1
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Periodic maintenance an d a djustment
6-16
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.
EAU69761
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. Locknut
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Periodic maintenance an d a djustment
6-18
6
ageing. Old and aged tires shall be
checked by tire specialists to ascertain
their suitability for further use.
WARNING
EWA10462
The front an
d rear tires shoul d b e of
the same make an d d esi gn, other-
wise the han dlin g characteristics of
the vehicle may be different, which
coul d lea d to an acci dent.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.
EAU22047
Adjustin g the clutch lever free
playMeasure the clutch lever free play as
shown.
Periodically check the clutch lever free
play and, if necessary, adjust it as fol-
lows.
1. Slide the rubber cover back at the clutch lever.
2. Loosen the locknut.
Front tire: Size:110/70-17 M/C 54S
Manufacturer/model: IRC/TRAIL WINNER GP-211F
Rear tire:
Size:140/70-17 M/C 66S
Manufacturer/model:
IRC/TRAIL WINNER GP-211R
1. Rubber cover
2. Clutch lever free play adjusting bolt
3. Locknut
4. Clutch lever free play
Clutch lever free play:10.0–15.0 mm (0.39–0.59 in)
4
1 2
(a)
(b)
3
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Periodic maintenance an d a djustment
6-19
6 3. To increase the clutch lever free
play, turn the clutch lever free play
adjusting bolt in direction (a). To
decrease the clutch lever free
play, turn the adjusting bolt in di-
rection (b).
TIPIf the specified clutch lever free play
could be obtained as described above,
skip steps 4–7.4. Fully turn the adjusting bolt at theclutch lever in direction (a) to loos-
en the clutch cable.
5. Loosen the locknut at the crank- case. 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
1. Locknut
2. Clutch lever free play adjusting nut (crank-
case)
1
2
(a)
(b)
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
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.
EAU22393
Checkin g the front an d rear
b rake pa dsThe front and rear brake pads must be
checked for wear at the intervals spec-
ified in the periodic maintenance and
lubrication chart.
EAU22434
Front brake pa ds
Each front 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.
EAU36721
Rear
brake pad s
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.
1. Wear indicator grooveZAUM2038
1. Wear indicator grooveZAUM2039
1
1
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Periodic maintenance an d a djustment
6-22
6
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 ducin g brakin g
performance.
 Clean the filler cap before re-
movin g. Use only DOT 4 b rake
flui d from a seale d container. 
Use only the specifie d 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 flui d
other than DOT 4 may result in a
harmful chemical reaction.
 Be careful that water or dust
d oes not enter the brake flui d
reservoir when refilling . 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 damag e painte d
surfaces or plastic parts. Always
clean up spille d flui d 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
1. Minimum level mark
1
ZAUM1057
1. Minimum level mark
Specified b rake flui d:
DOT 4ZAUM2040
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Periodic maintenance an d a djustment
6-24
6
4. If the drive chain slack is incorrect,
adjust it as follows. NOTICE: Im-
proper drive chain slack will
overloa d the en gine as well as
other vital parts of the motorcy-
cle an d can lead to chain slip-
pa ge or breakag e. To prevent
this from occurrin g, keep the
d rive chain slack within the
specifie d limits.
[ECA10572]
EAU3431B
To adjust the drive chain slack
Consult a Yamaha dealer before ad-
justing the drive chain slack. 1. Loosen the axle nut and the lock- nut on each side of the swingarm. 2. To tighten the drive chain, turn the
drive chain slack adjusting bolt on
each side of the swingarm in di-
rection (a). To loosen the drive
chain, turn the adjusting bolt on
each side of the swingarm in di-
rection (b), and then push the rear
wheel forward.
TIPUsing the alignment marks on each
side of the swingarm, make sure that
both drive chain pullers are in the same
position for proper wheel alignment.
3. Tighten the axle nut, then the lock-nuts to their specified torques.
4. Make sure that the drive chain pullers are in the same position,
the drive chain slack is correct,
and the drive chain moves
smoothly.
Drive chain slack:30.0–40.0 mm (1.18–1.57 in)
1. Drive chain slack adjusting bolt
2. Axle nut
3. Alignment marks
4. LocknutZAUM2042
23 1
4
(b)(a)
Tightenin g torques:
Axle nut: 85 N·m (8.5 kgf·m, 63 lb·ft)
Locknut:
15 N·m (1.5 kgf·m, 11 lb·ft)
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