he Wossner 8187D200 piston kit is engineered for Yamaha YZ80 models from 1988 to 1992, featuring a 50.00 mm bore for +2.00 mm oversize applications. Manufactured in Germany with a forged construction, this piston is built for strength and efficient heat dissipation. The elliptical design ensures an even load distribution under thermal expansion, minimising localised stress and reducing the risk of piston collapse. The kit includes all essential components for a complete engine rebuild.

Features

• Forged piston ensures high strength and thermal stability

• Designed for optimal heat transfer from combustion chamber to cylinder wall

• Elliptical profile evenly distributes thrust loads during expansion

• Minimises localised stress to help prevent piston failure

• Manufactured in Germany for consistent quality

Specifications

• Bore Size: 50.00 mm

• Actual Bore Diameter: 49.95 mm

• Stroke: 45.60 mm

• Display Displacement: 82 cm³

• Clearance: 0.05 mm

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

• Compression Height: 27.00 mm

Cross-Reference Wossner Part Numbers

• Piston Kit: 8187D200

• Lock: CW12

• Pin: WP091

• Ring Set: RSB5000

• Part No.: 56-W569+200.WO

Vehicle Fitments

• Yamaha YZ80 (1988–1992)