Yamaha YZF-R125 Service Manual: Troubleshooting
If the fuel pump fails to operate.
NOTE:
- Before troubleshooting, remove the following part(s):
1. Rider seat
2. Fuel tank
Circuit diagram
4. Main fuse
5. Main switch
9. Battery
17.Engine stop switch
25.ECU (engine control unit)
30.Fuel pump
64.Ignition fuse ...
Electrical components
1. Main switch
2. Clutch switch
3. Front brake light switch
4. Ignition coil
5. Throttle body sensor assembly (intake air
pressure sensor, intake air temperature
sensor, throttle position se ...
Other materials:
Checking the shift shaft
1. Check:
Shift shaft
Bends/damage/wear Replace.
Shift shaft spring
Damage/wear Replace.
Checking the stopper lever
1. Check:
Stopper lever
Bends/damage Replace.
Roller turns roughly Replace
the stopper
lever.
Stopper lever spring
Damage/wear Replace.
...
Aftermarket Parts, Accessories, and Modifications
While you may find aftermarket products
similar in design and quality to
genuine Yamaha accessories, recognize
that some aftermarket accessories
or modifications are not suitable because
of potential safety hazards to you
or others. Installing aftermarket products
or having other modif ...
Checking the valves and valve guides
The following procedure applies to all of the
valves and valve guides.
1. Measure:
Valve-stem-to-valve-guide clearance
Out of specification Replace the
valve
guide.
Valve-stem-to-valve-guide clearance =
Valve guide inside diameter "a" -
Valve stem diameter "b"
2. Replace:
...