The Wossner K8594D425-2 piston kit is a forged performance component tailored for Harley Davidson Twin Cam engines. Designed with a +4.25mm oversize bore (3.915") and a flat top configuration, these pistons deliver enhanced structural integrity and efficient heat management. Manufactured in Germany, the kit includes all essential components required for reliable engine assembly and operation.

Features

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  Forged high-performance pistons with skirt coating

  
  


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  Elliptical design ensures uniform load distribution under heat expansion

  
  


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  Optimised for effective heat transfer from combustion chamber to cylinder walls

  
  


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  Flat top pistons with 8.5:1 compression ratio

  
  


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  Includes rings, clips, and pins

  
  

Specifications

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  Bore size: 3.915" (+0.167", +4.25mm)

  
  


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  Compression ratio: 8.5:1

  
  


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  Quantity: 2 pistons per kit

  
  


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  Made in Germany

  
  

Cross-Reference OEM Part Numbers

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  Part No. 56-W9865.425.WO

  
  


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  Ring Set Part No. 995XSY

  
  

Vehicle Fitments

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  Harley Davidson 1453cc Twin Cam 1999–2009

  
  


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  Harley Davidson 1577cc Twin Cam 1999–2009

  
  


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  Twin Cam 88 (88 cu. in.) 1999–2006