Yamaha YZF-R125 Service Manual: Jumps out of gear

Shift pedal does not move

Shift shaft Improperly adjusted shift rod Bent shift shaft Shift drum and shift forks Foreign object in a shift drum groove Seized shift fork Bent shift fork guide bar Transmission ...

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 oi ...

Other materials:

Checking the clutch plates
The following procedure applies to all of the clutch plates. 1. Check: Clutch plate Damage Replace the clutch plates as a set. 2. Measure: Clutch plate warpage (with a surface plate and thickness gauge "1") Out of specification Replace the clutch plates as a set. ...

Tires
To maximize the performance, durability, and safe operation of your motorcycle, note the following points regarding the specified tires. Tire air pressure The tire air pressure should be checked and, if necessary, adjusted before each ride. WARNING Operation of this vehicle with impro ...

Cleaning the air filter element
NOTE: There is a check hose "1" at the bottom of the air filter case. If dust and/or water collects in this hose, clean the air filter element and air filter case. 1. Remove: Rider seat Refer to "GENERAL CHASSIS" on page 4-1. 2. Remove: Fuel tank Refer to "FUEL TANK" on page ...