Piston Kit 87-09 YFZ350 68.50, Wossner 8075D450 Yamaha ATV

This Wossner forged piston kit has a 68.50mm bore and is a +4.50 oversize component designed for select Yamaha two-stroke engines. Manufactured in Germany, the piston features an elliptical design that distributes thrust loads evenly and reduces the risk of localised pressure points and piston collapse. Its construction supports effective heat transfer from the combustion chamber to the cylinder wall, enhancing reliability under high-performance conditions.

Features

• Forged piston construction for increased structural integrity

• Elliptical design for uniform bearing surface under heat expansion

• Efficient combustion chamber heat transfer to cylinder walls

• Made in Germany

• Includes piston, pin, locks, and ring set

Specifications

• Bore Size: 68.50mm

• Actual Bore: 68.44mm

• Stroke: 54.00mm

• Clearance: 0.06mm

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

• Compression Height: 36.00mm

• Displacement: 347 cm³

Cross-Reference OEM Part Numbers

• Piston Kit Part No: 56-W513+450.WO

• Lock P/N: CW16

• Pin P/N: WP027

• Ring Set P/N: RSB6850 (x2)

Vehicle Fitments

• Yamaha YFZ 350 Banshee (1987–2007)

• Yamaha RD350 LC - YPVS (1980–1987)

• Yamaha RD350 AC (1950–2014)

• Yamaha RZ350 (1982–1990)

• Yamaha RD 350 (1973–1976)

• Yamaha RD 400 (1976)