2017 YAMAHA YS125 wheel

Periodic maintenance an d a djustment
6-19
6
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.
EAU51253
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 back the rubber cover at the clutch lever.
2. Loosen the locknut. 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. Slide back the rubber cover that is located further down the clutch
cable, and then loosen the lock-
nut.
1. Locknut
2. Clutch lever free play adjusting bolt
3. Rubber cover
4. Clutch lever free playClutch lever free play:10.0–15.0 mm (0.39–0.59 in)
321
(a)(b)
4
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Periodic maintenance an d a djustment
6-21
6
EAU39815
A djustin g the brake pe dal free
playMeasure the brake pedal free play at
the brake pedal end as shown.
Periodically check the brake pedal free
play and, if necessary, adjust it as fol-
lows.
To increase the brake pedal free play,
turn the brake pedal free play adjusting
nut at the brake rod in direction (a). To
decrease the brake pedal free play,
turn the adjusting nut in direction (b).
WARNING
EWA10681
 After a djustin g the drive chain
slack or removin g an d installin g
the rear wheel, always check
the brake pe dal free play.
 If proper a djustment cannot b e
o btaine d as descri bed , have a
Yamaha dealer make this ad -
justment.
 After a djustin g the brake ped al
free play, check the operation of
the brake li ght.
EAU22274
Brake li ght switchesThe brake light, which is activated by
the brake pedal and brake lever,
should come on just before braking
takes effect. If necessary, adjust the
rear brake light switch as follows, but
the front brake light switch should be
adjusted by a Yamaha dealer.
Turn the rear brake light switch adjust-
ing nut while holding the rear brake
light switch in place. To make the
brake light come on earlier, turn the ad-
justing nut in direction (a). To make the
brake light come on later, turn the ad-
justing nut in direction (b).
1. Brake pedal free playBrake pe dal free play:
10.0–20.0 mm (0.39–0.79 in)
1
1. Brake pedal free play adjusting nut
1
(a)
(b)
1. Rear brake light switch
2. Rear brake light switch adjusting nut
1 2
(a)
(b)
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Periodic maintenance an d a djustment
6-25
6 4. Place the motorcycle on the cen-
terstand.
5. To tighten the drive chain, turn the drive chain slack adjusting nut at
each end of the swingarm in direc-
tion (a). To loosen the drive chain,
turn the adjusting nut at each end
of the swingarm in direction (b),
and then push the rear wheel for-
ward.
TIPUsing the alignment marks on each
drive chain puller, make sure that both
drive chain pullers are in the same po-
sition for proper wheel alignment.
6. Take the motorcycle off the cen-terstand, and then put the side-
stand down.
7. Tighten both locknuts, and then tighten the axle nut and brake
torque rod nut to their specified
torques.
8. Adjust the brake pedal free play. (See page 6-21.)
WARNING
EWA10661
After a djustin g the brake pe dal free
play, check the operation of the
b rake li ght.9. Make sure that the drive chain
pullers are in the same position,
the drive chain slack is correct,
and the drive chain moves
smoothly.
EAU23018
Cleanin g an d lu bricatin g the
d rive chainThe drive chain must be cleaned and
lubricated at the intervals specified in
the periodic maintenance and lubrica-
tion chart, otherwise it will quickly wear
out, especially when riding in dusty or
wet areas. Service the drive chain as
follows.NOTICE
ECA10584
The drive chain must be lu bricated
after washin g the motorcycle, ri din g
in the rain or ri din g in wet areas.1. Remove all dirt and mud from the
drive chain with a brush or cloth.TIPFor a thorough cleaning, have a
Yamaha dealer remove the drive chain and soak it in solvent.2. Spray Yamaha chain lubricant or other suitable chain lubricant on
the entire chain, making sure that
all side plates and rollers have
been sufficiently oiled.
1. Washer
2. Alignment marks
1
2
Tightenin g torques:
Locknut: 7 N·m (0.7 kgf·m, 5.1 lb·ft)
Axle nut:
90 N·m (9.0 kgf·m, 65 lb·ft)
Brake torque rod nut: 18 N·m (1.8 kgf·m, 13 lb·ft)
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Periodic maintenance an d a djustment
6-30
6
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.
EAU2338A
BatteryThe battery is located behind panel B.
(See page 6-8.)
This model is equipped with a VRLA
(Valve Regulated Lead Acid) battery.
There is no need to check the electro-
lyte or to add distilled water. However,
the battery lead connections need to
be checked and, if necessary, tight-
ened.
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.1. Battery
2. Positive battery lead (red)
3. Negative battery lead (black)
2
1
3
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Periodic maintenance an d a djustment
6-36
6
3. Insert a new bulb into the socket,
push it in, and then turn it clock-
wise until it stops.
4. Install the lens by installing the screw. NOTICE: Do not over-
ti g hten the screw, otherwise the
lens may break.
[ECA11192] EAU78970
Replacin
g the license plate
lig ht bul b1. Remove the license plate light unit
by removing the nuts.
2. Remove the license plate light bulb socket (together with the
bulb) by pulling it out.
3. Remove the burnt-out bulb by pulling it out.
4. Insert a new bulb into the socket.
5. Install the socket (together with the bulb) by pushing it in.
6. Install the license plate light unit by installing the nuts.
EAU24361
Front wheel
EAUW3361
To remove the front wheel
WARNING
EWA10822
To avoi d injury, securely support the
vehicle so there is no dan ger of it
fallin g over.1. Take the vehicle off the center-
stand so that the front wheel is on
the ground, and then put the side-
stand down.
2. Loosen the front wheel axle nut.
1. Turn signal light bulb
1
1. License plate light unit
2. License plate light bulb
3. License plate light bulb socket
4. Nut
1
32
4
4
1. Axle nut
1
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Periodic maintenance an d a djustment
6-37
6 3. Place the vehicle on the center-
stand, and then remove the axle
nut.
4. Pull the wheel axle out, and then remove the wheel. NOTICE: Do
not apply the b rake after the
wheel an d b rake disc have b een
remove d, otherwise the brake
pa ds will be forced shut.
[ECA11073]
To install the front wheel
1. Lift the wheel up between the fork legs.TIPMake sure that there is enough space
between the brake pads before insert-
ing the brake disc into the caliper.
2. Insert the wheel axle, and then in-stall the axle nut.
3. Take the vehicle off the center- stand so that the front wheel is on
the ground, and then put the side-
stand down.
4. Tighten the axle nut to the speci- fied torque.
5. Push down hard on the handlebar several times to check for proper
fork operation.
EAU25081
Rear wheel
EAU78751
To remove the rear wheel
WARNING
EWA10822
To avoi d injury, securely support the
vehicle so there is no dan ger of it
fallin g over.1. Take the motorcycle off the cen-
terstand so that the rear wheel is
on the ground, and then put the
sidestand down.
2. Loosen the axle nut.
3. Disconnect the brake torque rod from the brake shoe plate by re-
moving the nut and the bolt.
1. Wheel axle
1
Tightenin g torque:
Axle nut: 59 N·m (5.9 kgf·m, 43 lb·ft)
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Periodic maintenance an d a djustment
6-38
6
4. Remove the brake pedal free play
adjusting nut, and then discon-
nect the brake rod from the brake
camshaft lever.
5. Loosen the drive chain puller lock-nut and the drive chain slack ad-
justing nut on both ends of the
swingarm.
6. Place the motorcycle on the cen- terstand.
7. Remove the axle nut and the washer, then pull the wheel axle
together with the washer out from
the right side, and then remove
the collars.
TIPA rubber mallet may be useful to tap
the wheel axle out.8. Push the wheel forward, and thenremove the drive chain from the
rear sprocket.
1. Axle nut
1
1. Brake pedal free play adjusting nut
2. Brake camshaft lever
3. Drive chain puller locknut
4. Drive chain slack adjusting nut
5. Brake shoe plate
6. Brake rod
7. Brake torque rod
8. Brake torque rod bolt
9. Brake torque rod nut
234
5
67
1
98
1. Washer
2. Collar
3. Wheel axle
2
1
2
31
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Periodic maintenance an d a djustment
6-39
6
TIPThe drive chain does not need to be
disassembled in order to remove and
install the wheel.9. Remove the wheel.
To install the rear wheel 1. Install the drive chain onto the rear sprocket.
2. Install the wheel by installing the collars on both sides and installing
the washer and the wheel axle
from the right side.
3. Install the washer and the axle nut.
4. Connect the brake rod to the brake camshaft lever, and then in-
stall the brake pedal free play ad-
justing nut onto the brake rod.
5. Connect the brake torque rod to the brake shoe plate by installing
the bolt and the nut.
6. Adjust the drive chain slack. (See page 6-24.)
7. Take the motorcycle off the cen- terstand so that the rear wheel is
on the ground, and then put the
sidestand down. 8. Adjust the brake pedal free play.
(See page 6-21.)
WARNING
EWA10661
After a djustin g the brake pe dal free
play, check the operation of the
b rake li ght.
EAU25853
Trou bleshootin gAlthough Yamaha motorcycles receive
a thorough inspection before shipment
from the factory, trouble may occur
during operation. Any problem in the
fuel, compression, or ignition systems,
for example, can cause poor starting
and loss of power.
The following troubleshooting chart
represents a quick and easy procedure
for checking these vital systems your-
self. However, should your motorcycle
require any repair, take it to a Yamaha
dealer, whose skilled technicians have
the necessary tools, experience, and
know-how to service the motorcycle
properly.
Use only genuine Yamaha replace-
ment parts. Imitation parts may look
like Yamaha parts, but they are often
inferior, have a shorter service life and
can lead to expensive repair bills.
WARNING
EWA15142
When checkin g the fuel system, do
not smoke, an d make sure there are
no open flames or sparks in the ar-
ea, inclu din g pilot li ghts from water
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