This Wossner forged piston kit is specifically engineered for Yamaha YZ250 (1992–1998) and WR250 (1992–1999) models with a +0.02mm oversize. Manufactured in Germany, it is designed for enhanced thermal conductivity and mechanical stability. The elliptical piston profile helps maintain an even load distribution during heat expansion, which reduces stress concentrations and prevents piston collapse. Its design supports effective combustion heat transfer to the cylinder wall, contributing to improved reliability under demanding conditions.

Features

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  Forged piston construction ensures high structural integrity

  
  


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  Elliptical design provides balanced expansion and bearing surface

  
  


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  Reduces localised stress and risk of collapse under thermal load

  
  


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  Supports effective heat dissipation from combustion chamber

  
  


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  Precision manufactured in Germany

  
  

Specifications

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  Bore Size: 68.02mm (+0.02mm oversize)

  
  


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  Actual Diameter: 67.96mm

  
  


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  Compression Height: 36.00mm

  
  


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  Stroke: 68.00mm

  
  


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  Displacement: 246 cm³

  
  


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  Piston Clearance: 0.06mm

  
  


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  Compression Ratio: 2-stroke (Wossner and OEM)

  
  

Cross-Reference OEM Part Numbers

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  Piston Kit Part No: 8023DC

  
  


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  Lock: CW18

  
  


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  Pin: WP033

  
  


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  Ring Set: RSB6800 x2

  
  


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  Rod: P2029

  
  

Vehicle Fitments

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  1992 Yamaha WR250

  
  


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  1992 Yamaha YZ250

  
  


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  1993 Yamaha WR250

  
  


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  1993 Yamaha YZ250

  
  


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  1994 Yamaha WR250

  
  


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  1994 Yamaha YZ250

  
  


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  1995 Yamaha WR250

  
  


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  1995 Yamaha YZ250

  
  


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  1996 Yamaha WR250

  
  


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  1996 Yamaha YZ250

  
  


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  1997 Yamaha WR250

  
  


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  1997 Yamaha YZ250

  
  


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  1998 Yamaha WR250

  
  


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  1998 Yamaha YZ250

  
  


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  1999 Yamaha WR250