WOSSNER 70mm PISTON KIT YAMAHA YZ250 83-87

Wossner forged piston kit for Yamaha YZ250 models from 1983 to 1987, featuring a 70.00 mm bore for performance applications requiring a +2.00 mm oversize. The piston is designed to optimise combustion efficiency and mechanical reliability. With an elliptical profile and advanced forging, it ensures uniform stress distribution, effective heat transfer, and reduced risk of piston deformation under high thermal loads. Precision-engineered and made in Germany.

Features

• Forged piston construction for enhanced strength and reliability

• Engineered for efficient heat transfer from combustion chamber to cylinder wall

• Elliptical design for balanced load distribution and minimised thermal stress

• Suitable for 2-stroke engine applications

• Manufactured in Germany

Specifications

• Bore: 70.00 mm

• Actual Bore Diameter: 69.94 mm

• Compression Height: 36.00 mm

• Display Volume: 246 cm³

• Stroke: 68.00 mm

• Clearance: 0.06 mm

• Compression Ratio: 2-stroke (Wossner and OEM)

Cross-Reference OEM Part Numbers

• Piston Kit Part No.: 8133D200

• Lock P/N: CW18

• Pin P/N: WP033

• Ring Set P/N: RSB7000 (x2)

• Rod P/N: P2048 (for 1983–1989 models)

• Alternate Part No.: 56-W560+200.WO

Vehicle Fitments

• Yamaha YZ250 (1983–1987)