The Wossner Forged Piston Kit (8957DA) with a standard 77mm bore is designed for the Yamaha YZ250F (2019). Engineered in Germany, this high-performance forged piston delivers strength, efficient heat transfer, and consistent load distribution. Its elliptical design minimises localised stress and helps prevent piston collapse under high-performance conditions.

Features

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  Forged construction for enhanced strength and durability

  
  


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  Designed for optimal combustion heat transfer to cylinder walls

  
  


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  Elliptical skirt profile ensures even thrust load distribution

  
  


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  Manufactured in Germany

  
  

Specifications

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  Piston Size: 77mm (STD)

  
  


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  Kit Part Number: 56-W8812.A.WO

  
  


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  Wossner Part Number: 8957DA

  
  


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  Piston Type: Forged

  
  

Cross-Reference OEM Part Numbers

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  B7B-11631-00-00

  
  

Vehicle Fitments

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  Yamaha YZ250F (2019)