2017 YAMAHA YS125 fuel

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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Consumer information
9-2
9
The model label is affixed to the frame
behind panel A. (See page 6-8.) Re-
cord the information on this label in the
space provided. This information will
be needed when ordering spare parts
from a Yamaha dealer.
EAU69910
Dia
gnostic connectorThe diagnostic connector is located as
shown.
EAU74701
Vehicle data recor din gThis model’s ECU stores certain vehi-
cle data to assist in the diagnosis of
malfunctions and for research and de-
velopment purposes. This data will be
uploaded only when a special Yamaha
diagnostic tool is attached to the vehi-
cle, such as when maintenance checks
or service procedures are performed.
Although the sensors and recorded
data will vary by model, the main data
points are:
 Vehicle status and engine perfor-
mance data
 Fuel-injection and emission-relat-
ed data
Yamaha will not disclose this data to a
third party except:  With the consent of the vehicle
owner
 Where obligated by law
 For use by Yamaha in litigation
 For general Yamaha-conducted
research purposes when the data
is not related to an individual vehi-
cle nor owner
1. Diagnostic connector
1
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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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