Yamaha YZF-R125 Service Manual: Throttle body

Checking the fuel pressure

1. Check: Pressure regulator operation a. Remove the fuel hose connector cover "1" and disconnect the fuel hose "2" from the fuel pump. CAUTION:Although the fuel has been removed from ...

Removing the throttle body

1. Extract the fuel in the fuel tank through the fuel tank filler hole with a pump. 2. Disconnect: Fuel hose WARNINGCover the fuel hose connections with a cloth when disconnecti ...

Other materials:

Checking the valves and valve guides
The following procedure applies to all of the valves and valve guides. 1. Measure: Valve-stem-to-valve-guide clearance Out of specification Replace the valve guide. Valve-stem-to-valve-guide clearance = Valve guide inside diameter "a" - Valve stem diameter "b" 2. Replace: ...

Bearings and oil seals
Install bearings "1" and oil seals "2" so that the manufacturer's marks or numbers are visible. When installing oil seals "1", lubricate the oil seal lips with a light coat of lithium-soap-based grease. Oil bearings liberally when installing, if appropriate. CAUTION:Do not spin th ...

Electrical components
1. Main switch 2. Clutch switch 3. Front brake light switch 4. Ignition coil 5. Throttle body sensor assembly (intake air pressure sensor, intake air temperature sensor, throttle position sensor) 6. FID (fast idle solenoid) 7. Rectifier/regulator 8. Lean angle sensor 9. Starting circui ...