This piston kit is designed for Yamaha R1 YZF1000 models from 2009 to 2015. It includes a set of four forged Wossner pistons with a standard bore size of 78.00mm. These pistons are built for high-performance and longevity, featuring an elliptical design that ensures even thrust load distribution and efficient heat expansion management. Manufactured in Germany, the kit is designed to match OEM compression characteristics while enhancing thermal reliability.

Features

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  Set of 4 forged Wossner pistons

  
  


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  Standard bore size (78.00mm, actual piston diameter 77.96mm)

  
  


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  Elliptical design for balanced pressure distribution under heat

  
  


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  Engineered for optimal combustion heat transfer

  
  


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  Made in Germany

  
  

Specifications

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  Part Number: K8812DA-4

  
  


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  Bore Size: 78.00mm (actual piston size 77.96mm)

  
  


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  Displacement: 1000cc

  
  


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  Display Displacement: 998cm³

  
  


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  Stroke: 52.20mm

  
  


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  Clearance: 0.04mm

  
  


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  Wossner Compression Ratio: OEM

  
  


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  OEM Compression Ratio: 12.70:1

  
  


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  Dome Volume: -3.30cm³

  
  


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  Compression Height: 22.80mm

  
  

Cross-Reference OEM Part Numbers

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  Clip: CW17

  
  


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  Piston Pin: WP083

  
  


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  Replacement Ring Set: 780XAS

  
  

Vehicle Fitments

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  Yamaha R1 YZF1000 2009–2015