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:

Faulty clutch
Clutch slips 1. Clutch Improperly assembled clutch Improperly adjusted clutch cable Loose or fatigued clutch spring Worn friction plate Worn clutch plate 2. Engine oil Incorrect oil level Incorrect oil viscosity (low) Deteriorated oil Clutch drags 1. Clutch Unevenly t ...

Checking the camshaft sprocket and timing chain guide
1. Check: Camshaft sprocket More than 1/4 tooth wear "a" Replace the camshaft sprocket, timing chain and crankshaft as a set. a. 1/4 tooth b. Correct 1. Timing chain roller 2. Camshaft sprocket 2. Check: Timing chain guide (exhaust side) Damage/wear Replace. ...

Checking the speed sensor
1. Check: Speed sensor output voltage Out of specification → Replace. a. Connect the pocket tester (DC 20 V) to the speed sensor coupler (wire harness end) as shown. Positive tester probe gray "1" Negative tester probe gray/black "2" b. Set the main switch to "ON". c. ...