Yamaha YZF-R125 Service Manual: Radiator

Cooling system

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Checking the radiator

1. Check: Radiator fins obstruction clean. Apply compressed air to the rear of the radiator. Damage  repair or replace. NOTE: Straighten any flattened fins with a thin, flat-head scre ...

Other materials:

Adjusting the engine idling speed
NOTE: Prior to adjusting the engine idling speed, the air filter element should be clean, and the engine should have adequate compression. 1. Start the engine and let it warm up for several minutes. 2. Remove: Rider seat Refer to "GENERAL CHASSIS" on page 4-1. 3. Lift the fuel tank. ...

Troubleshooting charts
Starting problems or poor engine performance Starting problems or poor engine performance Engine overheating WARNING Do not remove the radiator cap when the engine and radiator are hot. Scalding hot fluid and steam may be blown out under pressure, which could cause serious injury. Be ...

Checking the thermostat
1. Check: Thermostat Does not open at 80.5-83.5 C (176.9-182.3 F)  Replace. a. Suspend the thermostat "1" in a container "2" filled with water. b. Slowly heat the water "3". c. Place a thermometer "4" in the water. d. While stirring the water, observe the thermostat and th ...