2017 YAMAHA YS125 brake fluid

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

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)
UBT4E0E0.book Page 3 Thursday, November 17, 2016 10:55 AM

For your safety – pre-operation checks
4-1
4
EAU15599
Inspect your vehicle each time you use it to make sure the vehicle is in safe operating condition. Always follow the inspection
and maintenance procedures and schedules described in the Owner’s Manual.
WARNING
EWA11152
Failure to inspect or maintain the vehicle properly increases the possibility of an acci dent or equipment damag e.
Do not operate the vehicle if you fin d any pro blem. If a pro blem cannot be corrected b y the proce dures provi ded in
this manual, have the vehicle inspecte d b y a Yamaha dealer.Before using this vehicle, check the following points:
ITEM CHECKS PAGE
Fuel • Check fuel level in fuel tank.
• Refuel if necessary.
• Check fuel line for leakage. 3-8
En gine oil • Check oil level in engine.
• If necessary, add recommended oil to specified level.
• Check vehicle for oil leakage. 6-11
Front brake • Check operation.
• If soft or spongy, have Yamaha dealer bleed hydraulic system.
• Check brake pads for wear.
• Replace if necessary.
• Check fluid level in reservoir.
• If necessary, add specified brake fluid to specified level.
• Check hydraulic system for leakage. 6-22, 6-22
Rear brake • Check operation.
• Check pedal free play.
• Adjust if necessary. 6-21, 6-22
Clutch • Check operation.
• Lubricate cable if necessary.
• Check lever free play.
• Adjust if necessary. 6-19
UBT4E0E0.book Page 1 Thursday, November 17, 2016 10:55 AM

Periodic maintenance an d a djustment
6-4
6
EAU71342
General maintenance an d lu brication chartNO. ITEM CHECK OR MAINTENANCE JOB ODOMETER READING
ANNUAL
CHECK
1000 km
(600 mi) 6000 km
(3500 mi) 12000 km
(7000 mi) 18000 km
(10500 mi) 24000 km
(14000 mi)
1 *Dia
gnostic system
check • Perform dynamic inspection us-
ing Yamaha diagnostic tool.
• Check the error codes. √√√√√√
2 *Air filter element • Clean.
√√
•Replace. √√
3 Air filter case check
hose
• Clean.
√√√√√
4Clutch • Check operation.
•Adjust.
√√√√√
5 *Front brake • Check operation, fluid level, and
for fluid leakage.
• Replace brake pads if necessary. √√√√√√
6 *Rear brake • Check operation.
• Adjust brake pedal free play.
• Replace brake shoes if neces-
sary. √√√√√√
7 *Brake hose • Check for cracks or damage.
√√√√√
• Replace. Every 4 years
8 *Brake flui d • Change. Every 2 years
9 *Wheels • Check runout and for damage.
• Replace if necessary.
√√√√
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Periodic maintenance an d a djustment
6-7
6
EAU72690
TIP The air filter needs more frequent service if you are riding in unusually wet or dusty areas.
 Hydraulic brake service
• Regularly check and, if necessary, correct the brake fluid level.
• Every two years replace the internal components of the brake master cylinder and caliper, and change the brake fluid.
• Replace the brake hoses every four years and if cracked or damaged.29 *Throttle
grip hous-
in g an d cab le • Check operation and free play.
• Adjust the throttle cable free play
if necessary.
• Lubricate the throttle grip housing and cable. √√√√√
30 *Li
ghts, si gnals an d
switches • Check operation.
• Adjust headlight beam.
√√√√√√
NO. ITEM CHECK OR MAINTENANCE JOB
ODOMETER READING
ANNUAL
CHECK
1000 km
(600 mi) 6000 km
(3500 mi) 12000 km
(7000 mi) 18000 km
(10500 mi) 24000 km
(14000 mi)UBT4E0E0.book Page 7 Thursday, November 17, 2016 10:55 AM

Periodic maintenance an d a djustment
6-22
6
EAU22382
Checkin g the front b rake pads
an d rear b rake shoes The front brake pads and the rear
brake shoes must be checked for wear
at the intervals specified in the periodic
maintenance and lubrication chart.
EAU22432
Front brake pad s
Each front brake pad is provided with
wear indicator grooves, which allow
you to check the brake pad wear with-
out having to disassemble the brake.
To check the brake pad wear, check
the wear indicator grooves. If a brake
pad has worn to the point that the wear indicator grooves have almost disap-
peared, have a Yamaha dealer replace
the brake pads as a set.
EAU43171
Rear
brake shoes
The rear brake is provided with a wear
indicator, which allows you to check
the brake shoe wear without having to
disassemble the brake. To check the
brake shoe wear, check the position of
the wear indicator while applying the
brake. If a brake shoe has worn to the
point that the wear indicator reaches
the wear limit mark, have a Yamaha
dealer replace the brake shoes as a
set.
EAU32346
Checkin g the brake flui d levelBefore riding, check that the brake fluid
is above the minimum level mark.
Check the brake fluid level with the top
of the reservoir level. Replenish the
brake fluid if necessary.
WARNING
EWA15991
Improper maintenance can result in
loss of b raking a bility. O bserve
these precautions:
1. Brake pad wear indicator groove
1
1
1. Brake shoe wear limit mark
2. Brake shoe wear indicator
1
2
1. Minimum level mark
Specified b rake flui d:
DOT 41
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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.
UBT4E0E0.book Page 23 Thursday, November 17, 2016 10:55 AM

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