wheel YAMAHA YS125 2017 User Guide

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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Motorcycle care and stora ge
7-1
7
EAU37834
Matte color cautionNOTICE
ECA15193
Some mo dels are equipped with
matte colored finished parts. Be
sure to consult a Yamaha dealer for
a d vice on what prod ucts to use be-
fore cleanin g the vehicle. Usin g a
b rush, harsh chemical pro ducts or
cleanin g compoun ds when cleanin g
these parts will scratch or damag e
their surface. Wax also shoul d not
b e applie d to any matte colored fin-
ishe d parts.
EAU26005
CareWhile the open design of a motorcycle
reveals the attractiveness of the tech-
nology, it also makes it more vulnera-
ble. Rust and corrosion can develop
even if high-quality components are
used. A rusty exhaust pipe may go un-
noticed on a car, however, it detracts
from the overall appearance of a mo-
torcycle. Frequent and proper care
does not only comply with the terms of
the warranty, but it will also keep your
motorcycle looking good, extend its
life and optimize its performance.
Before cleanin g
1. Cover the muffler outlet with a plastic bag after the engine has
cooled down.
2. Make sure that all caps and cov- ers as well as all electrical cou-
plers and connectors, including
the spark plug cap, are tightly in-
stalled.
3. Remove extremely stubborn dirt, like oil burnt onto the crankcase,
with a degreasing agent and a
brush, but never apply such prod- ucts onto seals, gaskets, sprock-
ets, the drive chain and wheel
axles. Always rinse the dirt and
degreaser off with water.
Cleanin g
NOTICE
ECA10773
Avoi d usin g stron g aci dic wheel
cleaners, especially on spoked
wheels. If such pro ducts are
use d on har d-to-remove dirt, do
not leave the cleaner on the af-
fected area any lon ger than in-
structed . Also, thorou ghly rinse
the area off with water, immed i-
ately dry it, an d then apply a cor-
rosion protection spray.
 Improper cleanin g can d amage
plastic parts (such as cowlin gs,
panels, win dshiel ds, hea dlig ht
lenses, meter lenses, etc.) an d
the mufflers. Use only a soft,
clean cloth or spon ge with wa-
ter to clean plastic. However, if
the plastic parts cannot be thor-
ou ghly cleaned with water, di-
lute d mil d d eter gent with water
may be used . Be sure to rinse
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Motorcycle care and stora ge
7-2
7 off any d
etergent resi due usin g
plenty of water, as it is harmful
to plastic parts.
 Do not use any harsh chemical
prod ucts on plastic parts. Be
sure to avoi d using cloths or
spon ges which have been in
contact with stron g or a brasive
cleanin g prod ucts, solvent or
thinner, fuel ( gasoline), rust re-
movers or inhi bitors, brake flui d,
antifreeze or electrolyte.
 Do not use hi gh-pressure wash-
ers or steam-jet cleaners since
they cause water seepa ge an d
d eterioration in the followin g ar-
eas: seals (of wheel an d swin g-
arm bearin gs, fork an d b rakes),
electric components (couplers,
connectors, instruments,
switches an d lig hts), breather
hoses an d vents.
 For motorcycles equippe d with
a win dshield : Do not use stron g
cleaners or har d spon ges as
they will cause dullin g
or
scrat

ching . Some cleanin g
compoun ds for plastic may
leave scratches on the win d- shield
. Test the pro duct on a
small hidden part of the win d-
shield to make sure that it does
not leave any marks. If the win d-
shield is scratche d, use a quality
plastic polishin g compoun d af-
ter washin g.
After normal useRemove dirt with warm water, a mild
detergent, and a soft, clean sponge,
and then rinse thoroughly with clean
water. Use a toothbrush or bottlebrush
for hard-to-reach areas. Stubborn dirt
and insects will come off more easily if
the area is covered with a wet cloth for
a few minutes before cleaning.
After riding in the rain, near the sea oron salt-sprayed roadsSince sea salt or salt sprayed on roads
during winter are extremely corrosive
in combination with water, carry out
the following steps after each ride in
the rain, near the sea or on salt-
sprayed roads.
TIPSalt sprayed on roads in the winter
may remain well into spring.1. Clean the motorcycle with cold
water and a mild detergent, after
the engine has cooled down.
NOTICE: Do not use warm wa-
ter since it increases the corro-
sive action of the salt.
[ECA10792]
2. Apply a corrosion protection spray on all metal, including chrome-
and nickel-plated, surfaces to pre-
vent corrosion.
After cleanin g
1. Dry the motorcycle with a chamois or an absorbing cloth.
2. Immediately dry the drive chain and lubricate it to prevent it from
rusting.
3. Use a chrome polish to shine chrome, aluminum and stainless-
steel parts, including the exhaust
system. (Even the thermally in-
duced discoloring of stainless-
steel exhaust systems can be re-
moved through polishing.)
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Motorcycle care and stora ge
7-4
7 2. Fill up the fuel tank and add fuel
stabilizer (if available) to prevent
the fuel tank from rusting and the
fuel from deteriorating.
3. Perform the following steps to protect the cylinder, piston rings,
etc. from corrosion.a. Remove the spark plug cap and spark plug.
b. Pour a teaspoonful of engine oil into the spark plug bore.
c. Install the spark plug cap onto the spark plug, and then place
the spark plug on the cylinder
head so that the electrodes are
grounded. (This will limit spark-
ing during the next step.)
d. Turn the engine over several times with the starter. (This will
coat the cylinder wall with oil.)
WARNING! To prevent d am-
a g e or injury from sparkin g,
make sure to groun d the
spark plu g electro des while
turnin g the en gine over.
[EWA10952]
e. Remove the spark plug cap
from the spark plug, and then
install the spark plug and the
spark plug cap.
4. Lubricate all control cables and the pivoting points of all levers and
pedals as well as of the side-
stand/centerstand.
5. Check and, if necessary, correct the tire air pressure, and then lift
the motorcycle so that both of its
wheels are off the ground. Alterna-
tively, turn the wheels a little every
month in order to prevent the tires
from becoming degraded in one
spot.
6. Cover the muffler outlet with a plastic bag to prevent moisture
from entering it.
7. Remove the battery and fully char- ge it. Store it in a cool, dry place
and charge it once a month. Do
not store the battery in an exces-
sively cold or warm place [less
than 0 °C (30 °F) or more than 30
°C (90 °F)]. For more information
on storing the battery, see page
6-30.
TIPMake any necessary repairs before
storing the motorcycle.
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Specifications
8-1
8
Dimensions:Overall length:2005 mm (78.9 in)
Overall width:
735 mm (28.9 in)
Overall height: 1050 mm (41.3 in)
Seat height: 795 mm (31.3 in)
Wheelbase:
1320 mm (52.0 in)
Ground clearance: 150 mm (5.91 in)
Minimum turning radius: 2.2 m (7.22 ft)Wei ght:Curb weight:
129 kg (284 lb)Engine:Combustion cycle:
4-stroke
Cooling system: Air cooled
Valve train: SOHC
Number of cylinders:
Single cylinder
Displacement: 125 cm³
Bore × stroke:
52.4 × 57.9 mm (2.06 × 2.28 in)
Compression ratio:
10.0 : 1 Starting system:
Electric starter
Lubrication system: Wet sump
Engine oil:Recommended brand:
YAMALUBE
SAE viscosity grades: 10W-40, 20W-40
Recommended engine oil grade: API service SG type or higher, JASO
standard MA
Engine oil quantity:
Oil change:1.00 L (1.06 US qt, 0.88 Imp.qt)
With oil filter removal:
1.10 L (1.16 US qt, 0.97 Imp.qt)Air filter:Air filter element:Dry element
Fuel:Recommended fuel:Regular unleaded gasoline (Gasohol [E10]
acceptable)
Fuel tank capacity: 14 L (3.7 US gal, 3.1 Imp.gal)
Fuel reserve amount:
2.2 L (0.58 US gal, 0.48 Imp.gal)Fuel injection:Throttle body:ID mark:BT41 00Spark plu g(s):Manufacturer/model:
NGK/CPR8EA-9
Spark plug gap: 0.8–0.9 mm (0.031–0.035 in)Clutch:Clutch type:
Wet, multiple-discDrivetrain:Primary reduction ratio:3.409 (75/22)
Final drive:
Chain
Secondary reduction ratio: 3.071 (43/14)
Transmission type: Constant mesh 5-speed
Gear ratio:
1st:2.714 (38/14)
2nd:
1.789 (34/19)
010305070 90110
130 ˚F
-20 -10 0 10 20 3040
50 ˚C
SAE 10W-40
SAE 20W-40
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