Yamaha YZF-R125 Service Manual: Troubleshooting
The ignition system fails to operate (no spark or intermittent spark).
NOTE:
- Before troubleshooting, remove the following part(s):
1. Seats
2. Fuel tank
3. Right side cover
4. Left side panel
5. Left upper side cowling
Circuit diagram
2. Crankshaft position sensor
4. Main fuse
5. Main switch
8. Sidestand switch
9. Battery
17.Engine stop switch
23.Lean angle sensor
25.ECU (engine control unit)
26.Ignition coil
27.Spark ...
Other materials:
Checking the spark plug cap
1. Check:
Spark plug cap resistance
Out of specification Replace.
a. Remove the spark plug cap from the spark
plug lead.
b. Connect the pocket tester ( × 1k)
to the
spark plug cap as shown.
c. Measure the spark plug cap resistance. ...
Measuring the compression pressure
NOTE:
Insufficient compression pressure will result in a
loss of performance.
1. Measure:
Valve clearance
Out of specification →Adjust.
Refer to "ADJUSTING THE VALVE CLEARANCE"
on page 3-3.
2. Start the engine, warm it up for several minutes,
and then turn it off.
3. Remove:
...
Operation and important riding points
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
Failure to familiarize yourself with
the controls can lead to loss of control,
which could cause an accident
or injury.
TIP ...