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 cylinder and piston
1. Check: Piston wall Cylinder wall Vertical scratches Replace the cylinder, and replace the piston and piston rings as a set. 2. Measure: Piston-to-cylinder clearance a. Measure cylinder bore "C" with the cylinder bore gauge. NOTE: Measure cylinder bore "C" by takin ...

Checking the timing chain tensioner
1. Check: Timing chain tensioner Cracks/damage/rough movement Replace. a. Lightly press the timing chain tensioner rod into the timing chain tensioner housing by hand. NOTE: While pressing the timing chain tensioner rod, wind it clockwise with a thin screwdriver "1" until it stops. b. ...

Checking the front brake hose
1. Check: Brake hose "1" Cracks/damage/wear  Replace. 2. Check: Brake hose holder "2" Loose connection Tighten the holder bolt. 3. Hold the vehicle upright and apply the front brake several times. 4. Check: Brake hose Brake fluid leakage Replace the da ...