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TM 250MX Big Bore Kit
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KTM 65SX Big Bore Kits/Big Bore Stroker Kits

  


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*Please be sure to clean out your crankcases before installing your big bore top end. There may be foreign material still inside from a prior top end failure, which will quickly ruin your new big bore kit. Also check your crankshaft to make sure your lower end bearing is not ready to fail. If you need us to check it for you, then send your entire engine to us when purchasing our big bore kit service.

 69cc Big Bore Kit Service  Send us your cylinder and head. Includes: Bore Cylinder and Re-Plate, Head Modification for bigger bore, Big Bore Porting, 47mm Wiseco or Vertex Piston Kit, Top End Gasket Kit, and Return Shipping.
Price $475.00   For 1997-08 65SX 

71cc Big Bore Kit Service  Send us your cylinder, power valve, and head. Includes: Bore Cylinder and Re-Plate, Head Modification for bigger bore, Big Bore Porting, any Power Valve Modification needed, 47mm Piston Kit, Top End Gasket Kit, and Return Shipping.
Price $475.00   For 2009-11 65SX 

 69cc Big Bore Parts Kit Only  47mm Vertex Piston Kit #22858200, Top End Gasket Kit, and Top End Bearing.
Price $122.00   For 1997-08 65SX 

 69cc Big Bore Parts Kit Only  47mm Wiseco Piston Kit #746M04700, Top End Gasket Kit, and Top End Bearing.
Price $156.00   For 1997-08 65SX 

71cc Big Bore Parts Kit Only  47mm Wiseco Piston Kit #864M04700, Top End Gasket Kit, and Top End Bearing.
Price $156.00   For 2009-11 65SX