Yamaha YZF-R125 Service Manual: Lubricating the drive chain

The drive chain consists of many interacting parts. If the drive chain is not maintained properly, it will wear out quickly. Therefore, the drive chain should be serviced, especially when the vehicle is used in dusty areas.

This vehicle has a drive chain with small rubber O-rings between each side plate. Steam cleaning, high-pressure washing, certain solvents, and the use of a coarse brush can damage these O-rings. Therefore, use only kerosene to clean the drive chain. Wipe the drive chain dry and thoroughly lubricate it with engine oil or chain lubricant that is suitable for O-ring chains.

Do not use any other lubricants on the drive chain since they may contain solvents that could damage the O-rings.


    Adjusting the drive chain slack
    NOTE: The drive chain slack must be checked at the tightest point on the chain. CAUTION:A drive chain that is too tight will overload the engine and other vital parts, and one that ...

    Checking and adjusting the steering head
    1. Stand the vehicle on a level surface WARNINGSecurely support the vehicle so that there is no danger of it falling over. NOTE: Place the vehicle on a suitable stand so that the ...

    Other materials:

    Circuit diagram
    4. Main fuse 5. Main switch 9. Battery 14.Neutral switch 25.ECU (engine control unit) 31.Fuel sender 34.Rear brake light switch 35.Front brake light switch 37.Tail/brake light 38.Rear right turn signal light 39.Rear left turn signal light 40.Front right turn signal light 41.Front lef ...

    Checking the crankshaft
    1. Measure: Crankshaft runout Out of specification Replace the crankshaft, bearing or both. NOTE: Turn the crankshaft slowly. 2. Measure: Big end side clearance Out of specification Replace the crankshaft. 3. Measure: Crankshaft width Out of specification&nbs ...

    Ignition circuit cut-off system
    The ignition circuit cut-off system (comprising the sidestand switch, clutch switch and neutral switch) has the following functions. It prevents starting when the transmission is in gear and the sidestand is up, but the clutch lever is not pulled. It prevents starting when the t ...

    2026 Copyright www.yam-r125.net |