2017 YAMAHA YS125 light

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

Table of contents
Replacing the fuse.........................6-31
Replacing the headlight bulb.........6-33
Replacing the auxiliary light
bulb ...........................................6-34
Replacing the brake/tail light
bulb ............................................6-35
Replacing a turn signal light bulb ............................................6-35
Replacing the license plate light bulb ............................................6-36
Front wheel....................................6-36
Rear wheel.....................................6-37
Troubleshooting ............................6-39
Troubleshooting chart ...................6-41
Motorcycle care an d stora ge ..........7-1
Matte color caution .........................7-1
Care .................................................7-1
Storage ............................................7-3
Specifications ....................................8-1
Consumer information .....................9-1
Identification numbers .....................9-1
Diagnostic connector ......................9-2
Vehicle data recording ....................9-2
In dex ................................................10-1
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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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Safety information
1-5
1operator and may limit control
ability, therefore, such accesso-
ries are not recommended.
 Use caution when adding electri-
cal accessories. If electrical ac-
cessories exceed the capacity of
the motorcycle’s electrical sys-
tem, an electric failure could re-
sult, which could cause a
dangerous loss of lights or engine
power.
Aftermarket Tires an d Rims
The tires and rims that came with your
motorcycle were designed to match
the performance capabilities and to
provide the best combination of han-
dling, braking, and comfort. Other
tires, rims, sizes, and combinations
may not be appropriate. Refer to page
6-17 for tire specifications and more in-
formation on replacing your tires.
Transportin g the Motorcycle
Be sure to observe following instruc-
tions before transporting the motorcy-
cle in another vehicle.  Remove all loose items from the
motorcycle. 
Check that the fuel cock (if
equipped) is in the “OFF” position
and that there are no fuel leaks.
 Point the front wheel straight
ahead on the trailer or in the truck
bed, and choke it in a rail to pre-
vent movement.
 Shift the transmission in gear (for
models with a manual transmis-
sion).
 Secure the motorcycle with tie-
downs or suitable straps that are
attached to solid parts of the mo-
torcycle, such as the frame or up-
per front fork triple clamp (and not,
for example, to rubber-mounted
handlebars or turn signals, or
parts that could break). Choose
the location for the straps carefully
so the straps will not rub against
painted surfaces during transport.
 The suspension should be com-
pressed somewhat by the tie-
downs, if possible, so that the mo-
torcycle will not bounce exces-
sively during transport.
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Description
2-1
2
EAU10411
Left view
4
7
1
2
8
9
3
6
5
10
1. Auxiliary light (page 6-34)
2. Headlight (page 6-33)
3. Fuel tank cap (page 3-8)
4. Idle adjusting screw (page 6-16)
5. Air filter element (page 6-14)
6. Seat (page 3-11)
7. Shock absorber assembly spring preload adjusting ring (page 3-11)
8. Brake/tail light (page 6-35) 9. License plate light (page 6-36)
10.Shift pedal (page 3-6)
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Description
2-2
2
EAU10421
Right view
3,4
1
2
5
6
7
8
9
1. Shock absorber assembly spring preload adjusting ring (page 3-11)
2. Owner’s tool kit (page 6-2)
3. Battery (page 6-30)
4. Fuses (page 6-31)
5. Engine oil filter element (page 6-11)
6. Engine oil drain bolt (page 6-11)
7. Engine oil filler cap (page 6-11)
8. Brake pedal (page 3-7) 9. Rear brake light switch (page 6-21)UBT4E0E0.book Page 2 Thursday, November 17, 2016 10:55 AM

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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