Yamaha YZF-R125 Service Manual: Removing the piston

Removing the piston


1. Remove:

  • Piston pin clips "1"

  • Piston pin "2"

  • Piston "3"

CAUTION:

Do not use a hammer to drive the piston pin out.

NOTE:

  • Before removing the piston pin clip, cover the crankcase opening with a clean rag to prevent the piston pin clip from falling into the crankcase.

  • Before removing the piston pin, deburr the piston pin clip groove and the piston pin bore area.

    If both areas are deburred and the piston pin is still difficult to remove, remove it with the piston pin puller set "4".


Removing the piston


2. Remove:

  • Top ring

  • 2nd ring

  • Oil ring

NOTE:

When removing a piston ring, open the end gap with your fingers and lift the other side of the ring over the piston crown.

Removing the piston


    Cylinder and piston
    ...

    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. Mea ...

    Other materials:

    Checking the steering
    Worn or loose steering bearings may cause danger. Therefore, the operation of the steering must be checked as follows at the intervals specified in the periodic maintenance and lubrication chart. Place a stand under the engine to raise the front wheel off the ground. WARNING! To ...

    Preparation for removal and disassembly
    1. Before removal and disassembly, remove all dirt, mud, dust and foreign material. 2. Use only the proper tools and cleaning equipment. Refer to "SPECIAL TOOLS" on page 1-8. 3. When disassembling, always keep mated parts together. This includes gears, cylinders, pistons and other part ...

    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 ...

    2025 Copyright www.yam-r125.net |