This Wossner forged piston kit with a 47.50mm bore is a standard size replacement for Yamaha YZ85 models from 2002 to 2019. Engineered for durability and thermal efficiency in two-stroke engines, this German-made piston utilises advanced materials and design features to ensure consistent performance under high-stress conditions.

Features

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  Forged construction provides maximum strength and longevity

  
  


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  Designed to facilitate optimal combustion heat transfer to the cylinder walls

  
  


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  Elliptical profile ensures even load distribution and reduces piston collapse risk

  
  


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  Made in Germany

  
  

Specifications

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  Bore: 47.50mm

  
  


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  Actual Bore: 47.45mm

  
  


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  Engine Displacement: 85 cm³

  
  


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  Stroke: 47.80mm

  
  


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  Clearance: 0.05mm

  
  


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  Compression Ratio: 2-stroke (Wossner and OEM)

  
  


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  Compression Height: 26.00mm

  
  


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  Lock Part Number: CW14

  
  


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  Pin Part Number: WP058

  
  


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  Ring Set Part Number: RSB4750

  
  


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  Con Rod Kit Part Number: P2008

  
  

Cross-Reference OEM Part Numbers

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  5PA-11631-10-A0

  
  


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  09104832

  
  


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  805M04750

  
  

Vehicle Fitments

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  Yamaha YZ85 2002-2019