oil YAMAHA YS125 2017 User Guide

Periodic maintenance an d a djustment
6-23
6 
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-
moving . Use only DOT 4 b rake
flui d from a seale d container.
 Use only the specified 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 ddin g a brake flui d
other than DOT 4 may result in a
harmful chemical reaction.
 Be careful that water does not
enter the brake flui d reservoir
when refillin g. Water will si gnifi-
cantly lower the boilin g point of
the flui d an d may result in vapor
lock.
NOTICE
ECA17641
Brake flui d may damag e painted
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
fluid level goes down suddenly, have a
Yamaha dealer check the cause before further riding.
EAU22724
Chan gin g the brake flui d Have a Yamaha dealer change the
brake fluid at the intervals specified in
the periodic maintenance and lubrica-
tion chart. In addition, have the oil seals
of the brake master cylinder and cali-
per as well as the brake hose replaced
at the intervals listed below or whenev-
er they are damaged or leaking.
 Oil seals: Replace every two
years.
 Brake hose: Replace every four
years.
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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
6-29
6
EAU23273
Checkin g the front forkThe condition and operation of the
front fork must be checked as follows
at the intervals specified in the periodic
maintenance and lubrication chart.
To check the con dition
Check the inner tubes for scratches,
damage and excessive oil leakage.
To check the operation 1. Place the vehicle on a level surfa- ce and hold it in an upright posi-
tion. WARNING! To avoi d injury,
securely support the vehicle so
there is no dan ger of it fallin g
over.
[EWA10752]
2. While applying the front brake, push down hard on the handle-
bars several times to check if the
front fork compresses and re-
bounds smoothly.
NOTICE
ECA10591
If any d amage is foun d or the front
fork does not operate smoothly,
have a Yamaha dealer check or re-
pair it.
EAU45512
Checkin g the steerin gWorn or loose steering bearings may
cause danger. Therefore, the operation
of the steering must be checked as fol-
lows at the intervals specified in the
periodic maintenance and lubrication
chart.
1. Place the vehicle on the center- stand. WARNING! To avoi d inju-
ry, securely support the vehicle
so there is no dan ger of it fallin g
over.
[EWA10752]
2. Hold the lower ends of the front fork legs and try to move them for-
ward and backward. If any free
play can be felt, have a Yamaha
dealer check or repair the steer-
ing.
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Periodic maintenance an d a djustment
6-33
6
EAU78872
Replacin g the hea dlig ht bul bThis model is equipped with a halogen
bulb headlight. If the headlight bulb
burns out, replace it as follows.NOTICE
ECA10651
Take care not to d amage the follow-
in g parts:
 Hea dlig ht bul b
Do not touch the g lass part of
the hea dlig ht bul b to keep it free
from oil, otherwise the transpar-
ency of the glass, the luminosity
of the b ulb, an d the bul b life will
b e ad versely affected . Thor-
ou ghly clean off any dirt an d fin-
g erprints on the head lig ht bul b
usin g a cloth moistened with al-
cohol or thinner.
 Hea dlig ht lens
Do not affix any type of tinted
film or stickers to the hea dlig ht
lens.
Do not use a hea dlig ht bul b of a
watta ge hi gher than specifie d.
1. Remove the headlight unit side
covers by removing the screw on
each side. 2. Remove the bolt on each side.
3. Loosen the headlight unit stay
bolt, and then tilt the headlight unit
forward.1. Do not touch the glass part of the bulb.
1. Headlight unit side cover
2. Screw
1
2
1. Headlight unit side cover
2. Screw
3. Headlight unit stay bolt
1. Bolt
213
1
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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
7-3
7
4. To prevent corrosion, it is recom-
mended to apply a corrosion pro-
tection spray on all metal,
including chrome- and nickel-plat-
ed, surfaces.
5. Use spray oil as a universal clean- er to remove any remaining dirt.
6. Touch up minor paint damage caused by stones, etc.
7. Wax all painted surfaces.
8. Let the motorcycle dry completely before storing or covering it.
WARNING
EWA11132
Contaminants on the b rakes or tires
can cause loss of control.  Make sure that there is no oil or
wax on the brakes or tires.
 If necessary, clean the brake
d iscs an d b rake linin gs with a
re gular brake disc cleaner or
acetone, an d wash the tires with
warm water an d a mil d d eter-
g ent. Before rid ing at hi gher
spee ds, test the motorcycle’s
b rakin g performance an d cor-
nerin g b ehavior.
NOTICE
ECA10801
 Apply spray oil an d wax spar-
in gly an d make sure to wipe off
any excess.
 Never apply oil or wax to any
rubber an d plastic parts, b ut
treat them with a suita ble care
prod uct.
 Avoi d using abrasive polishin g
compoun ds as they will wear
away the paint.TIP Consult a Yamaha dealer for ad-
vice on what products to use.
 Washing, rainy weather or humid
climates can cause the headlight
lens to fog. Turning the headlight
on for a short period of time will
help remove the moisture from the
lens.
EAU43204
Stora geShort-term
Always store your motorcycle in a cool,
dry place and, if necessary, protect it
against dust with a porous cover. Be
sure the engine and the exhaust sys-
tem are cool before covering the mo-
torcycle.NOTICE
ECA10811
 Storin g the motorcycle in a
poorly ventilated room or cover-
in g it with a tarp, while it is still
wet, will allow water an d humi d-
ity to seep in an d cause rust.
 To prevent corrosion, avoi d
d amp cellars, stab les (because
of the presence of ammonia)
an d areas where stron g chemi-
cals are stored .Long-term
Before storing your motorcycle for sev-
eral months: 1. Follow all the instructions in the “Care” section of this chapter.
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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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Specifications
8-2
8
3rd:1.318 (29/22)
4th: 1.045 (23/22)
5th:
0.875 (21/24)
Chassis:Frame type:Diamond
Caster angle:
25.0 °
Trail: 82 mm (3.2 in)Front tire:Type:
Tubeless
Size: 2.75-18M/C 42P
Manufacturer/model: CHENG SHIN/C910Rear tire:Type:Tubeless
Size: 100/80-18M/C 59P
Manufacturer/model:
CHENG SHIN/C905Loading:Maximum load:171 kg (377 lb)
(Total weight of rider, passenger, cargo
and accessories)
Tire air pressure (measured on cold
tires):1 person:
Front: 175 kPa (1.75 kgf/cm², 25 psi)
Rear:
200 kPa (2.00 kgf/cm², 29 psi)
2 persons: Front:
175 kPa (1.75 kgf/cm², 25 psi)
Rear: 225 kPa (2.25 kgf/cm², 33 psi)
Maximum load: Front: 175 kPa (1.75 kgf/cm², 25 psi)
Rear: 250 kPa (2.50 kgf/cm², 36 psi)Front wheel:Wheel type:Cast wheel
Rim size: 18M/C x MT1.85Rear wheel:Wheel type:Cast wheel
Rim size: 18M/C x MT2.15Unified brake system:Operation:Activated by front brakeFront brake:Type:
Hydraulic single disc brake Specified brake fluid:
DOT 3 or 4
Rear brake:Type:
Mechanical leading trailing drum brakeFront suspension:Type:Telescopic fork
Spring:
Coil spring
Shock absorber: Hydraulic damper
Wheel travel: 120 mm (4.7 in)Rear suspension:Type:Swingarm
Spring: Coil spring
Shock absorber:
Hydraulic damper
Wheel travel: 112 mm (4.4 in)Electrical system:System voltage:
12 V
Ignition system: TCI
Charging system: AC magnetoBattery:Model:YTX5L-BS
UBT4E0E0.book Page 2 Wednesday, December 21, 2016 11:07 AM

10-1
10
IndexAAir filter element and check hose,
cleaning .............................................. 6-14
Auxiliary light bulb, replacing ................ 6-34BBattery .................................................. 6-30
Brake and clutch levers, checking and lubricating ........................................... 6-27
Brake and shift pedals, checking and
lubricating ........................................... 6-26
Brake fluid, changing ............................ 6-23
Brake fluid level, checking .................... 6-22
Brake lever .............................................. 3-7
Brake lever free play, checking............. 6-20
Brake light switches.............................. 6-21
Brake pads and shoes, checking ......... 6-22
Brake pedal............................................. 3-7
Brake pedal free play, adjusting ........... 6-21
Brake/tail light bulb, replacing .............. 6-35CCables, checking and lubricating ......... 6-26
Care ........................................................ 7-1
Catalytic converters .............................. 3-10
Centerstand and sidestand, checking and lubricating .................................... 6-28
Clutch lever ............................................. 3-6
Clutch lever free play, adjusting ........... 6-19
Cowling and panels, removing and installing................................................ 6-8DData recording, vehicle ........................... 9-2
Diagnostic connector.............................. 9-2
Dimmer switch ........................................ 3-5
Drive chain, cleaning and lubricating .... 6-25 Drive chain slack .................................. 6-24
EEco indicator light................................... 3-2
Engine break-in ...................................... 5-3
Engine idling speed .............................. 6-16
Engine oil and oil filter element ............ 6-11
Engine serial number .............................. 9-1
Engine trouble warning light ................... 3-2FFront fork, checking ............................. 6-29
Fuel ......................................................... 3-8
Fuel consumption, tips for reducing ...... 5-3
Fuel tank cap .......................................... 3-8
Fuse, replacing ..................................... 6-31HHandlebar switches ................................ 3-5
Headlight bulb, replacing ..................... 6-33
High beam indicator light ....................... 3-2
Horn switch ............................................ 3-5IIdentification numbers ............................ 9-1
Ignition circuit cut-off system ............... 3-13
Indicator lights and warning light ........... 3-2LLicense plate light bulb, replacing........ 6-36MMain switch/steering lock....................... 3-1
Maintenance and lubrication, periodic ... 6-4
Maintenance, emission control
system.................................................. 6-3
Matte color, caution ............................... 7-1
Model label ............................................. 9-1
Multi-function meter unit ........................ 3-3
NNeutral indicator light ..............................3-2PParking ....................................................5-4
Part locations ..........................................2-1
Pass switch .............................................3-5SSafety information ...................................1-1
Seat .......................................................3-11
Shifting ....................................................5-2
Shift pedal ...............................................3-6
Shock absorber assemblies, adjusting .............................................3-11
Sidestand ..............................................3-12
Spark plug, checking ............................6-10
Specifications .........................................8-1
Starting the engine ..................................5-1
Start switch .............................................3-6
Steering, checking ................................6-29
Storage ...................................................7-3
Swingarm pivots, lubricating ................6-28TThrottle grip and cable, checking and lubricating ...........................................6-26
Throttle grip free play, checking ...........6-16
Tires ......................................................6-17
Tool kit ....................................................6-2
Troubleshooting ....................................6-39
Troubleshooting chart ...........................6-41
Turn signal indicator light........................3-2
Turn signal light bulb, replacing ............6-35
Turn signal switch ...................................3-5VValve clearance .....................................6-17
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