Yamaha YZF-R125 Service Manual: Checking the cylinder head breather hose
1. Remove:
- Left side panel Refer to "GENERAL CHASSIS" on page 4-1.
2. Check:
- Cylinder head breather hose "1"
Cracks/damage → Replace.
Loose connection → Connect properly.
| CAUTION: Make sure the cylinder head breather hose is routed correctly. |
3. Install:
- Left side panel Refer to "GENERAL CHASSIS" on page 4-1.
Checking the fuel line
1. Remove:
Left side panel
Refer to "GENERAL CHASSIS" on page 4-1.
2. Lift the fuel tank. (Do not disconnect the fuel
hose, drain hose
3. Check:
Fuel hose "1"
Cracks/damage → Replac ...
Checking the exhaust system
1. Check:
Exhaust assembly "1"
Cracks/damage → Replace.
Exhaust pipe gasket "2"
Exhaust gas leaks → Replace.
2. Check:
Tightening torques of the exhaust pipe nuts
"3" an ...
Other materials:
Troubleshooting method
The engine operation is not normal and the
engine trouble warning light comes on.
1. Check:
Fault code number
a. Check the fault code number displayed on
the FI diagnostic tool.
b. Identify the faulty system with the fault code.
Refer to "Self-Diagnostic Function table".
c. Identi ...
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
...
Checking the rectifier/regulator
1. Check:
Rectifier/regulator output voltage
Out of specification → Replace the
rectifier/
regulator.
a. Set the engine tachometer to the spark plug
lead.
b. Connect the pocket tester (DC 20 V) to the
rectifier/regulator coupler as shown.
Positive tester probe
red "1"
Negat ...