Yamaha YZF-R125 Service Manual: Troubleshooting

Starting circuit cut-off system operation

If the engine stop switch is set to " " and the main switch is set to "ON" (both switches are closed), the starter motor can only operate if at least one of the following conditions is met: ...

Charging system

...

Other materials:

Starting failures
Engine 1. Cylinder and cylinder head - Loose spark plug - Loose cylinder head or cylinder - Damaged cylinder head gasket - Damaged cylinder gasket - Worn or damaged cylinder - Incorrect valve clearance - Improperly sealed valve - Incorrect valve-to-valve-seat contact - Incorrect valve timi ...

Installing the relay arm
1. Lubricate: Spacers Bearings Oil seals Bolts (unthreaded shaft portion only) 2. Install: Bearing "1" (to the relay arm) Oil seal "2" (to the relay arm) 3. Rear shock absorber assembly 4. Relay arm 5. Connecting arm A. Left side B. Right side ...

Replacing the air filter element and cleaning the check hose
The air filter element should be replaced at the intervals specified in the periodic maintenance and lubrication chart. Have a Yamaha dealer replace the air filter element more frequently if you are riding in unusually wet or dusty areas. In addition, the air filter check hose must be ...