transmission YAMAHA YS125 2017 Owners Manual

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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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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Instrument and control functions
3-3
3
TIPConsider the following tips to reduce
fuel consumption:
 Avoid high engine speeds during
acceleration.
 Travel at a constant speed.
 Select the transmission gear that
is appropriate for the vehicle
speed.
EAU78331
Multi-function meter unit
WARNING
EWA12423
Be sure to stop the vehicle before
makin g any settin g chan ges to the
multi-function meter unit. Chan gin g
settin gs while ri din g can d istract the
operator an d increase the risk of an
acci dent.The multi-function meter unit is
equipped with the following:
 speedometer 
odometer
 tripmeter
 tachometer
 fuel meter
 transmission gear display
TIPBe sure to turn the key to “ ” be-
fore using the “RESET/SELECT”
button.
 For the UK: To switch the speed-
ometer and odometer/tripmeter
displays between kilometers and
miles, push the “RESET/SELECT”
button for two seconds. However,
the display units can be switched
only while the odometer is dis-
played.Speed ometer
The speedometer shows the vehicle’s
traveling speed.
1. Tachometer
2. Fuel meter
3. Transmission gear display
4. Speedometer
5. Odometer/tripmeter
6. “RESET/SELECT” button
2
3
4
1
5
6
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Instrument and control functions
3-5
3 Transmission
gear display
This display shows the selected gear.
The neutral position, however, is not
displayed, it is indicated by the neutral
indicator light.
EAU1234M
Han dle bar switchesLeft
Ri ght
EAU12352
Pass switch “ ”
Press this switch to flash the headlight.TIPWhen the dimmer switch is set
to “ ”, the passing switch has no ef-
fect.
EAU12401
Dimmer switch “ / ”
Set this switch to “ ” for the high
beam and to “ ” for the low beam.
EAU12461
Turn si gnal switch “ / ”
To signal a right-hand turn, push this
switch to “ ”. To signal a left-hand
turn, push this switch to “ ”. When
released, the switch returns to the cen-
ter position. To cancel the turn signal
lights, push the switch in after it has re-
turned to the center position.
EAU12501
Horn switch “ ”
Press this switch to sound the horn.
1. Transmission gear display
1
1. Pass switch “ ”
2. Dimmer switch “ / ”
3. Turn signal switch “ / ”
4. Horn switch “ ”
1. Start switch “ ”
12
34
1
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Instrument and control functions
3-6
3
EAU12713
Start switch “ ”
Push this switch to crank the engine
with the starter. See page 5-1 for start-
ing instructions prior to starting the en-
gine.
EAU12822
Clutch leverThe clutch lever is located on the left
side of the handlebar. To disengage
the clutch, pull the lever toward the
handlebar grip. To engage the clutch,
release the lever. The lever should be
pulled rapidly and released slowly for
smooth clutch operation.
The clutch lever is equipped with a
clutch switch, which is part of the igni-
tion circuit cut-off system. (See page
3-13.)
EAU12872
Shift pe dalThe shift pedal is located on the left
side of the motorcycle and is used in
combination with the clutch lever when
shifting the gears of the 5-speed con-
stant-mesh transmission equipped on
this motorcycle.
1. Clutch lever
1
1. Shift pedal
1
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Instrument and control functions
3-13
3
EAU78340
Ig nition circuit cut-off systemThe ignition circuit cut-off system
(comprising the sidestand switch,
clutch switch and neutral switch) has
the following functions.
 It prevents starting when the
transmission is in gear and the
sidestand is up, but the clutch le-
ver is not pulled.
 It prevents starting when the
transmission is in gear and the
clutch lever is pulled, but the side-
stand is still down.
 It cuts the running engine when
the transmission is in gear and the
sidestand is moved down.
Periodically check the operation of the
ignition circuit cut-off system accord-
ing to the following procedure.UBT4E0E0.book Page 13 Thursday, November 17, 2016 10:55 AM

Instrument and control functions
3-14
3
With the engine turned off:
1. Move the sidestand down.
2. Turn the key on.
3. Shift the transmission into the neutral position.
4. Push the start switch.
Does the engine start?
With the engine still running:
5. Move the sidestand up.
6. Keep the clutch lever pulled.
7. Shift the transmission into gear.
8. Move the sidestand down.
Does the engine stall?
After the engine has stalled:
9. Move the sidestand up.
10. Keep the clutch lever pulled.
11. Push the start switch.
Does the engine start?
The system is OK. The motorcycle can be ridden. The sidestand switch may not be working correctly.
The motorcycle should not be ridden
until
checked by a Yamaha dealer.
The clutch switch may not be working correctly.
The motorcycle should not be ridden until
checked by a Yamaha dealer.
YES NO YES NO YES NO
The neutral switch may not be working correctly.
The motorcycle should not be ridden until
checked by a Yamaha dealer. The vehicle must be placed on the center-
stand during this inspection.If a malfunction is noted, have a Yamaha
dealer check the system before riding.
WA R N I N G
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Operation and important rid ing points
5-1
5
EAU15952
Read the Owner’s Manual carefully to
become familiar with all controls. If
there is a control or function you do not
understand, ask your Yamaha dealer.
WARNING
EWA10272
Failure to familiarize yourself with
the controls can lead to loss of con-
trol, which coul d cause an acci dent
or injury.
EAUM3150
TIPThis model is equipped with a lean an-
gle sensor to stop the engine in case of
a turnover. To start the engine after a
turnover, be sure to turn the main
switch to “ ” and then to “ ”. Failing
to do so will prevent the engine from
starting even though the engine will
crank when pushing the start switch.
EAU78350
Startin g the en gineIn order for the ignition circuit cut-off
system to enable starting, one of the
following conditions must be met:
 The transmission is in the neutral
position.
 The transmission is in gear with
the clutch lever pulled and the
sidestand up.
See page 3-13 for more informa-
tion.
1. Turn the key to “ ”. The engine trouble warning light
should come on for a few sec-
onds, then go off.NOTICE
ECA23970
If the warnin g li ght does not come
on initially when the key is turne d
to “ ”, or if the warnin g li ght re-
mains on, see pag e 3-2 for the warn-
in g lig ht circuit check.2. Shift the transmission into the
neutral position. The neutral indi-
cator light should come on. If not,
ask a Yamaha dealer to check the
electrical circuit.
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Operation and important ri din g points
5-2
5
3. Start the engine by pushing the
start switch.
If the engine fails to start when us-
ing the start switch, release it, wait
a few seconds, and then try again.
Each starting attempt should be
as short as possible to preserve
the battery. Do not crank the en-
gine more than 10 seconds on any
one attempt.
NOTICE
ECA11043
For maximum en gine life, never ac-
celerate har d when the en gine is
col d!
EAU16673
Shiftin gShifting gears lets you control the
amount of engine power available for
starting off, accelerating, climbing hills,
etc.
The gear positions are shown in the il-
lustration.TIPTo shift the transmission into the neu-
tral position, press the shift pedal down
repeatedly until it reaches the end of its
travel, and then slightly raise it.
NOTICE
ECA10261
Even with the transmission in
the neutral position, d o not
coast for lon g period s of time
with the en gine off, an d d o not
tow the motorcycle for lon g d is-
tances. The transmission is
properly lu bricated only when
the en gine is runnin g. Ina de-
quate lu brication may d amage
the transmission.
 Always use the clutch while
chan gin g g ears to avoi d d am-
a g in g the en gine, transmission,
an d d rive train, which are not
d esi gne d to withstan d the
shock of force d shiftin g.
1. Shift pedal
2. Neutral position
1
N
2 3
4
5
1
2
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Periodic maintenance an d a djustment
6-24
6
EAU22762
Drive chain slackThe drive chain slack should be
checked before each ride and adjusted
if necessary.
EAU22799
To check the drive chain slack
1. Place the motorcycle on the cen- terstand.
2. Shift the transmission into the neutral position.
3. Measure the drive chain slack as shown. 4. If the drive chain slack is incorrect,
adjust it as follows. NOTICE: Im-
proper drive chain slack will
overloa d the en gine as well as
other vital parts of the motorcy-
cle an d can lead to chain slip-
pa ge or b reakag e. To prevent
this from occurrin g, keep the
d rive chain slack within the
specifie d limits.
[ECA10572]
EAU78831
To adjust the drive chain slack
Consult a Yamaha dealer before ad-
justing the drive chain slack. 1. Take the motorcycle off the cen- terstand, and then put the side-
stand down.
2. Loosen the brake pedal free play adjusting nut, brake torque rod
nut, and axle nut.
3. Loosen the drive chain puller lock-nut at each end of the swingarm.
1. Drive chain slackDrive chain slack:40.0–50.0 mm (1.57–1.97 in)
1
1. Brake pedal free play adjusting nut
2. Brake torque rod nut
1. Axle nut
2. Drive chain slack adjusting nut
3. Drive chain puller locknut
4. Drive chain puller
1
2
4 31
2
(a)(b)
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