2021 YAMAHA MT-125 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 lights............................................ 3-2
Multi-function meter unit ................ 3-4
Handlebar switches ...................... 3-12
Clutch lever .................................. 3-13
Shift pedal .................................... 3-14
Brake lever.................................... 3-14
Brake pedal .................................. 3-14
ABS .............................................. 3-15
Fuel tank cap ................................ 3-16
Fuel ............................................... 3-16
Fuel tank breather hose and overflow hose ............................ 3-18
Catalytic converter ....................... 3-19
Seat .............................................. 3-19
Helmet holder ............................... 3-20
Sidestand ..................................... 3-20
Ignition circuit cut-off system ....... 3-21 For your safety – pre-operation
checks
............................................... 4-1
Operation an d important ri din g
points ................................................. 5-1
Engine break-in ............................... 5-1
Starting the engine .......................... 5-2
Shifting ............................................ 5-3
Tips for reducing fuel consumption ................................ 5-4
Parking ............................................ 5-4
Perio dic maintenance an d
a d justment ........................................ 6-1
Tool kit ............................................ 6-2
Periodic maintenance chart for the emission control system .............. 6-3
General maintenance and lubrication chart ........................... 6-4
Removing and installing cowlings... 6-8
Checking the spark plug ................. 6-8
Canister ........................................... 6-9
Engine oil and oil filter element ..... 6-10
Why Yamalube .............................. 6-12
Coolant.......................................... 6-13
Replacing the air filter element
and cleaning the check hose..... 6-14
Adjusting the engine idling speed ......................................... 6-15
Adjusting the throttle grip free play ............................................ 6-16 Valve clearance............................. 6-16
Tires .............................................. 6-17
Cast wheels .................................. 6-19
Adjusting the clutch lever free
play ............................................ 6-19
Checking the front brake lever free play..................................... 6-20
Adjusting the brake pedal free
play ............................................ 6-21
Brake light switches ..................... 6-21
Checking the front and rear brake pads .......................................... 6-22
Checking the brake fluid level ...... 6-22
Changing the brake fluid .............. 6-24
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............... 6-27
Checking and lubricating the brake and clutch levers ............. 6-27
Checking and lubricating the
sidestand................................... 6-28
Lubricating the rear suspension ... 6-28
Checking the front fork ................. 6-29
Checking the steering................... 6-29
Checking the wheel bearings ....... 6-30UB6GE1E0.book Page 1 Thursday, July 30, 2020 1:08 PM

Description
2-2
2
EAU10421
Right view
1
2
3
4
5
6
7
1. Rear turn signal lights (page 6-33)
2. Seat lock (page 3-19)
3. Front turn signal light (page 6-33)
4. Engine oil filter element (page 6-10)
5. Dipstick (page 6-10)
6. Brake pedal (page 3-14)
7. Rear brake fluid reservoir (page 6-22)UB6GE1E0.book Page 2 Thursday, July 30, 2020 1:08 PM

Description
2-3
2
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Controls and instruments
1
2
3
4
5
6
7
8
1. Clutch lever (page 3-13)
2. Left handlebar switches (page 3-12)
3. Multi-function meter unit (page 3-4)
4. Main switch/steering lock (page 3-1)
5. Front brake fluid reservoir (page 6-22)
6. Right handlebar switches (page 3-12)
7. Throttle grip (page 6-16)
8. Brake lever (page 3-14)
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For your safety – pre-operation checks
4-1
4
EAU1559B
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.
• Check fuel tank breather hose and overflow hose for obstructions, cracks or
damage, and check hose connections. 3-16, 3-18
En gine oil • Check oil level in engine.
• If necessary, add recommended oil to specified level.
• Check vehicle for oil leakage. 6-10
Coolant • Check coolant level in reservoir.
• If necessary, add recommended coolant to specified level.
• Check cooling system for leakage. 6-13
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
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For your safety – pre-operation checks
4-2
4
Rear 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
Clutch • Check operation.
• Lubricate cable if necessary.
• Check lever free play.
• Adjust if necessary.
6-19
Throttle grip • Make sure that operation is smooth.
• Check throttle grip free play.
• If necessary, have Yamaha dealer adjust throttle grip free play and lubricate ca-
ble and grip housing. 6-16, 6-26
Control ca bles • Make sure that operation is smooth.
• Lubricate if necessary. 6-26
Drive chain • Check chain slack.
• Adjust if necessary.
• Check chain condition.
• Lubricate if necessary.
6-24, 6-25
Wheels an d tires • Check for damage.
• Check tire condition and tread depth.
• Check air pressure.
• Correct if necessary.
6-17, 6-19
Brake an d shift pe dals • Make sure that operation is smooth.
• Lubricate pedal pivoting points if necessary. 6-27
Brake an d clutch levers • Make sure that operation is smooth.
• Lubricate lever pivoting points if necessary.
6-27
Si destan d • Make sure that operation is smooth.
• Lubricate pivot if necessary.
6-28
ITEM CHECKS PAGE
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Periodic maintenance an d a djustment
6-4
6
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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 • 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, fluid level, and
for fluid leakage.
• Replace brake pads if necessary. √√√√√√
7 *Brake hoses • 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. √√√√
10 *Tires • Check tread depth and for dam-
age.
• Replace if necessary.
• Check air pressure.
• Correct if necessary. √√√√√
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Periodic maintenance an d a djustment
6-7
6
EAU72750
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 cylinders and calipers, and change the brake fluid.
• Replace the brake hoses every four years and if cracked or damaged.30 *Throttle g
rip hous-
in g an d ca ble • Check operation and free play.
• Adjust the throttle cable free play
if necessary.
• Lubricate the throttle grip housing and cable. √√√√√
31 *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)
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Periodic maintenance an d a djustment
6-22
6
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Checkin g the front an d rear
b rake pa dsThe front and rear brake pads must be
checked for wear at the intervals spec-
ified in the periodic maintenance and
lubrication chart.
EAU22421
Front brake pa ds
Each front brake pad is provided with a
wear indicator groove, which allows
you to check the brake pad wear with-
out having to disassemble the brake.
To check the brake pad wear, check
the wear indicator groove. If a brake
pad has worn to the point that the wear indicator groove has almost disap-
peared, have a Yamaha dealer replace
the brake pads as a set.
EAU36721
Rear
brake pad s
Each rear 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.
EAU40262
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.
Front brake
1. Wear indicator grooveZAUM1466
1
1. Wear indicator grooveZAUM1601
1
1
1. Minimum level mark
1
ZAUM1057
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