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 connections
Check the leads, couplers, and connectors for
stains, rust, moisture, etc.
1. Disconnect:
Lead
Coupler
Connector
2. Check:
Lead
Coupler
Connector
Moisture → Dry with an air blower.
Rust/stains → Connect and disconnect several
times.
3. Check:
All co ...
Installing the front brake master cylinder
1. Install:
Brake master cylinder "1"
Brake master cylinder holder "2"
NOTE:
Install the brake master cylinder holder with the
arrow mark "a" pointing forward.
Align the end of the brake master cylinder holder
with the punch mark "b" on the handlebar.
First, tighten the front bo ...
Adjusting the engine idling speed
The engine idling speed must be
checked and, if necessary, adjusted as
follows at the intervals specified in the
periodic maintenance and lubrication
chart.
The engine should be warm before
making this adjustment.
Remove panel A.
Check the engine idling speed
and, if necessary, ...