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
The spark plug is an important engine
component, which is easy to check.
Since heat and deposits will cause any
spark plug to slowly erode, the spark
plug should be removed and checked
in accordance with the periodic maintenance
and lubrication chart. In addition,
the condition of the ...
Fuel
Make sure there is sufficient gasoline in
the tank.
WARNING
Gasoline and gasoline vapors are
extremely flammable. To avoid fires
and explosions and to reduce the
risk of injury when refueling, follow
these instructions.
Before refueling, turn off the engine
and be sure that no on ...
Outline of the fi system
The main function of a fuel supply system is to provide fuel to the
combustion chamber at the optimum
air-fuel ratio in accordance with the engine operating conditions and the
atmospheric temperature. In
the conventional carburetor system, the air-fuel ratio of the mixture that is
supplied t ...