PISTON KIT 98-01 YZ125 54.50, WOSSNER 8091D050 YAMAHA MX

This Wossner piston kit with a 54.50mm bore (+0.50mm oversize) is built for Yamaha YZ125 and WR125 models from 1998 to 2001. Forged in Germany, the piston is engineered for high durability and effective heat management, making it suitable for demanding two-stroke engine applications.

Features

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  Forged piston for superior strength and reliability

  
  


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  Optimised heat transfer from combustion chamber to cylinder wall

  
  


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  Elliptical design reduces localised pressure and evenly distributes thrust loads

  
  


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  Precision-manufactured in Germany

  
  

Specifications

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  Bore size: 54.50 mm

  
  


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  Actual piston size: 54.45 mm

  
  


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  Display (cm³): 125

  
  


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  Stroke (mm): 54.50

  
  


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  Clearance (mm): 0.05

  
  


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  Compression ratio: 2-stroke (Wossner and OEM)

  
  


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  Compression height (mm): 28.00

  
  

Vehicle Fitments

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  1998 Yamaha WR125

  
  


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  1998 Yamaha YZ125 Base

  
  


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  1999 Yamaha WR125

  
  


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  1999 Yamaha YZ125 Base

  
  


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  2000 Yamaha WR125

  
  


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  2000 Yamaha YZ125 Base

  
  


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  2001 Yamaha WR125

  
  


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  2001 Yamaha YZ125 Base

  
  

Included Components

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  Piston: Wossner PN# 8091D050

  
  


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  Lock: PN# CW15

  
  


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  Pin: PN# WP032

  
  


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  Ring Set: PN# RSB5450

  
  


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  Rod: PN# P2019