Yamaha YZF-R125 Service Manual: Troubleshooting
- General information
- Starting failures
- Incorrect engine idling speed
- Poor medium-and-high-speed performance
- Shift pedal does not move
- Jumps out of gear
- Faulty clutch
- Overheating
- Poor braking performance
- Faulty front fork legs
- Unstable handling
- Faulty lighting or signaling system
Checking the fid (fast idle solenoid)
1. Disconnect:
FID (fast idle solenoid) coupler
2. Check:
FID (fast idle solenoid) resistance
a. Disconnect the FID (fast idle solenoid) coupler
from the FID.
b. Connect the pocket t ...
General information
NOTE:
The following guide for troubleshooting does not
cover all the possible causes of trouble. It should
be helpful, however, as a guide to basic troubleshooting.
Refer to the relative procedu ...
Other materials:
Intake air pressure sensor
1. Check:
Intake air pressure sensor output voltage
Out of specification Replace the throttle
body.
a. Connect the pocket tester (DC 20 V) to the
throttle body sensor assembly coupler as
shown.
Positive tester probe
pink/white "1"
Negative tester probe
gray/black "2"
...
Checking the timing chain and timing chain guide
1. Check:
Timing chain
Damage/stiffness Replace the
timing
chain and camshaft sprocket as a set.
2. Check:
Timing chain guide (intake side)
Damage/wear Replace.
Checking the oil strainer
1. Check:
Oil strainer
Damage Replace.
Contaminants Clean with solvent.
...
Checking the crankshaft
1. Measure:
Crankshaft runout
Out of specification Replace
the crankshaft,
bearing or both.
NOTE:
Turn the crankshaft slowly.
2. Measure:
Big end side clearance
Out of specification Replace
the crankshaft.
3. Measure:
Crankshaft width
Out of specification&nbs ...