2017 YAMAHA YS125 steering

Table of contentsSafety information ............................ 1-1
Description ....................................... 2-1
Left view ......................................... 2-1
Right view ....................................... 2-2
Controls and instruments ............... 2-3
Instrument an d control functions ... 3-1
Main switch/steering lock............... 3-1
Indicator lights and warning light ............................................. 3-2
Multi-function meter unit ................ 3-3
Handlebar switches ........................ 3-5
Clutch lever .................................... 3-6
Shift pedal ...................................... 3-6
Brake lever...................................... 3-7
Brake pedal .................................... 3-7
Fuel tank cap .................................. 3-8
Fuel ................................................. 3-8
Catalytic converters ..................... 3-10
Seat .............................................. 3-11
Adjusting the shock absorber assemblies ................................ 3-11
Sidestand ..................................... 3-12
Ignition circuit cut-off system ....... 3-13 For your safety – pre-operation
checks
............................................... 4-1
Operation an d important ri din g
points ................................................. 5-1
Starting the engine .......................... 5-1
Shifting ............................................ 5-2
Tips for reducing fuel consumption ................................ 5-3
Engine break-in ............................... 5-3
Parking ............................................ 5-4
Perio dic maintenance an d
a d justment ........................................ 6-1
Owner’s tool kit ............................... 6-2
Periodic maintenance chart for the emission control system .............. 6-3
General maintenance and lubrication chart ........................... 6-4
Removing and installing the
cowling and panels ...................... 6-8
Checking the spark plug ............... 6-10
Engine oil and oil filter element ..... 6-11
Cleaning the air filter element and cleaning the check hose ............ 6-14
Adjusting the engine idling
speed ......................................... 6-16
Checking the throttle grip free play ............................................ 6-16
Valve clearance ............................. 6-17
Tires .............................................. 6-17 Cast wheels .................................. 6-19
Adjusting the clutch lever free
play ............................................ 6-19
Checking the brake lever free play ............................................ 6-20
Adjusting the brake pedal free play ............................................ 6-21
Brake light switches ..................... 6-21
Checking the front brake pads
and rear brake shoes ............... 6-22
Checking the brake fluid level ...... 6-22
Changing the brake fluid ............. 6-23
Drive chain slack........................... 6-24
Cleaning and lubricating the
drive chain ................................. 6-25
Checking and lubricating the cables ........................................ 6-26
Checking and lubricating the throttle grip and cable ............... 6-26
Checking and lubricating the
brake and shift pedals............... 6-26
Checking and lubricating the brake and clutch levers ............. 6-27
Checking and lubricating the centerstand and sidestand........ 6-28
Lubricating the swingarm
pivots......................................... 6-28
Checking the front fork ................. 6-29
Checking the steering................... 6-29
Checking the wheel bearings ....... 6-30
Battery .......................................... 6-30UBT4E0E0.book Page 1 Thursday, November 17, 2016 10:55 AM

Safety information
1-4
1
tents, can create unstable han-
dling or a slow steering re-
sponse.
 This vehicle is not desi gne d to
pull a trailer or to be attached to
a si decar.
Genuine Yamaha Accessories
Choosing accessories for your vehicle
is an important decision. Genuine
Yamaha accessories, which are avail- able only from a Yamaha dealer, have
been designed, tested, and approved
by Yamaha for use on your vehicle.
Many companies with no connection
to Yamaha manufacture parts and ac-
cessories or offer other modifications
for Yamaha vehicles. Yamaha is not in
a position to test the products that
these aftermarket companies produce.
Therefore, Yamaha can neither en-
dorse nor recommend the use of ac-
cessories not sold by Yamaha or
modifications not specifically recom-
mended by Yamaha, even if sold and
installed by a Yamaha dealer. Aftermarket Parts, Accessories, an
d
Mo difications
While you may find aftermarket prod-
ucts similar in design and quality to
genuine Yamaha accessories, recog-
nize that some aftermarket accesso-
ries or modifications are not suitable
because of potential safety hazards to
you or others. Installing aftermarket
products or having other modifications
performed to your vehicle that change
any of the vehicle’s design or operation
characteristics can put you and others
at greater risk of serious injury or
death. You are responsible for injuries
related to changes in the vehicle.
Keep the following guidelines in mind,
as well as those provided under “Load-
ing” when mounting accessories.  Never install accessories or carry
cargo that would impair the per-
formance of your motorcycle.
Carefully inspect the accessory
before using it to make sure that it
does not in any way reduce
ground clearance or cornering
clearance, limit suspension travel, steering travel or control opera-
tion, or obscure lights or reflec-
tors.
• Accessories fitted to the han- dlebar or the front fork area can
create instability due to improp-
er weight distribution or aerody-
namic changes. If accessories
are added to the handlebar or
front fork area, they must be as
lightweight as possible and
should be kept to a minimum.
• Bulky or large accessories may seriously affect the stability of
the motorcycle due to aerody-
namic effects. Wind may at-
tempt to lift the motorcycle, or
the motorcycle may become
unstable in cross winds. These
accessories may also cause in-
stability when passing or being
passed by large vehicles.
• Certain accessories can dis- place the operator from his or
her normal riding position. This
improper position limits the
freedom of movement of the
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Description
2-3
2
EAU10431
Controls and instruments
12 34 678
5
1. Clutch lever (page 3-6)
2. Left handlebar switches (page 3-5)
3. Main switch/steering lock (page 3-1)
4. Multi-function meter unit (page 3-3)
5. Front brake fluid reservoir (page 6-22)
6. Right handlebar switch (page 3-5)
7. Throttle grip (page 6-16)
8. Brake lever (page 3-7)
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Instrument and control functions
3-1
3
EAU10462
Main switch/steerin g lockThe main switch/steering lock controls
the ignition and lighting systems, and is
used to lock the steering. The various
positions are described below.
EAU78890
(on)
All electrical circuits are supplied with
power and the vehicle lights are turned
on. The engine can be started. The key
cannot be removed.
TIPTo prevent draining the battery, do not
leave the key in the on position for an
extended time without the engine run-
ning.
EAU54301
(off)
All electrical systems are off. The key
can be removed.
WARNING
EWA16371
Never turn the key to “ ” or “LOCK”
while the vehicle is movin g. Other-
wise the electrical systems will be
switched off, which may result in
loss of control or an acci dent.
EAU73820
LOCK
The steering is locked, and all electrical
systems are off. The key can be re-
moved. To lock the steering
1. Turn the handlebars all the way to
the left or right.
2. With the key in the “ ” position, push the key in and turn it to
“LOCK”.
3. Remove the key.TIPIf the steering will not lock, try turning
the handlebars back to the right or left
slightly.
LOCK
1. Push.
2. Turn.12
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Instrument and control functions
3-2
3
To unlock the steering
Insert the key and turn it to “ ”.
EAU1100D
In
dicator li ghts an d warnin g
lig ht
EAU11022
Turn si gnal in dicator li ght “ ”
This indicator light flashes when a turn
signal light is flashing.
EAU11061
Neutral in dicator li ght “ ”
This indicator light comes on when the
transmission is in the neutral position.
EAU11081
Hi gh beam in dicator li ght “ ”
This indicator light comes on when the
high beam of the headlight is switched
on.
EAU78310
En gine trou ble warnin g li ght “ ”
This warning light comes on if a prob-
lem is detected in the engine or other
vehicle control system. If this occurs,
have a Yamaha dealer check the on-
board diagnostic system.
The electrical circuit of the warning
light can be checked by turning the key
to “ ”. The warning light should come
on for a few seconds, and then go off.
If the warning light does not come on
initially when the key is turned to “ ”,
or if the warning light remains on, have
a Yamaha dealer check the vehicle.
EAUE2572
Eco in dicator li ght “ECO”
This indicator light comes on when the
vehicle is being operated in an environ-
mentally friendly, fuel-efficient manner.
The indicator light goes off when the
vehicle is stopped.
1. Turn.
1
1. Turn signal indicator light “ ”
2. Neutral indicator light “ ”
3. High beam indicator light “ ”
4. Eco indicator light “ECO”
5. Engine trouble warning light “ ”
1
2
3
4
5
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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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Consumer information
9-1
9
EAU53562
Id entification num bersRecord the vehicle identification num-
ber, engine serial number, and the
model label information in the spaces
provided below. These identification
numbers are needed when registering
the vehicle with the authorities in your
area and when ordering spare parts
from a Yamaha dealer.
VEHICLE IDENTIFICATION NUMBER:
ENGINE SERIAL NUMBER:
MODEL LABEL INFORMATION:
EAU26401
Vehicle i dentification num ber
The vehicle identification number is
stamped into the steering head pipe.
Record this number in the space pro-
vided.TIPThe vehicle identification number is
used to identify your motorcycle and
may be used to register your motorcy-
cle with the licensing authority in your
area.
EAU26442
En gine serial num ber
The engine serial number is stamped
into the crankcase.
EAU36981
Mo del la bel
1. Vehicle identification number
1
1. Engine serial number
1. Model label
1
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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