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Piston Mod

Here is an example of the modification required to use the Yamaha RZ or Yamaha Banshee style pistons in your Air cooled Yamaha RD 350 and 400.


  • Stock Pro-X Piston on the intake side
  • Draw a reference line strait across.
  • Use a Dremel cut off wheel and carefully cut on the top of the reference line
  • After it is cut, use a smooth cut flat file to even the surface.
  • chamfer the front edge.
  • Use fine sandpaper to finish the surface.
If you do not feel comfortable performing this procedure. Let us know and for $25.00 we will perform this operation on a set of pistons.  (that is two pistons)