PISTON KIT 01-04 YFM660 102.00, WOSSNER 8507D200 YAMAHA ATV

This Wossner Piston Kit with a 102.00mm bore (+2.00 oversize) is engineered for Yamaha XTZ660 motorcycles and YFM660 series ATVs. Designed and manufactured in Germany, this forged piston provides superior strength, efficient heat transfer, and optimal expansion control through its elliptical design. It maintains OEM compression characteristics while offering enhanced durability under extreme operating conditions.

Features

• Forged construction for maximum strength and durability

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

• Elliptical profile ensures uniform thrust load distribution and reduces piston collapse risk

• Manufactured in Germany

Specifications

• Bore: 102.00 mm

• Measured Bore: 101.93 mm

• Clearance: 0.07 mm

• Compression Ratio: OEM

• OEM Compression Ratio: 9.20:1

• Dome Volume: -0.30 cm³

• Compression Height: 27.00 mm

• Display: 660 cm³

• Hub Stroke: 84.00 mm

• Part No.: 56-W8507+200.WO

• Piston Kit Model: 8507D200 (+2.00)

Cross-Reference OEM Part Numbers

• Not specified

Vehicle Fitments

• Yamaha XTZ660 Tenere 1991–1998

• Yamaha XTZ660 Raptor 1991–1998

• Yamaha YFM660R Raptor 2001–2004

• Yamaha YFM660F Grizzly 2001–2004