Yamaha YZF-R125 Service Manual: Balancer gear

Installing the shift shaft

1. Install: Stopper lever "1" Stopper lever spring "2" NOTE: Install the stopper lever spring as shown in the illustration. Hook the ends of the stopper lever spring onto the stoppe ...

Removing the primary drive gear and balancer gears

1. Loosen: Primary drive gear nut "1" NOTE: Place the aluminum plate "a" between the balancer drive gear "2" and the balancer driven gear "3", and then loosen the primary drive gear nut. ...

Other materials:

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 disconnecting them. Residual pressure in the fuel lines could cause fuel to spurt out when removing the h ...

Engine specifications
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Throttle position sensor
1. Check: Throttle position sensor a. Connect the digital circuit tester to the terminals of the throttle body sensor assembly coupler as shown. Positive tester probe → gray/red terminal "1" Negative tester probe → gray/black terminal "2" b. Measure the throttle pos ...