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


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