The Wossner 8601DA forged piston kit features a 95.00mm bore and is designed for Yamaha YFZ450 models from 2004 to 2005. Manufactured in Germany, this piston is built for optimal strength, heat transfer, and durability under high-performance conditions. Its elliptical shape ensures even pressure distribution and minimizes the risk of piston collapse due to thermal expansion.

Features

• Forged piston construction for enhanced strength and durability


• Designed for efficient heat transfer from the combustion chamber to cylinder walls


• Elliptical profile provides uniform bearing surface under heat expansion


• Reduces localized pressure and prevents piston collapse


• Manufactured in Germany

Specifications

• Bore: 95.00 mm


• Actual Bore Diameter: 94.95 mm


• Display: 449 cm³


• Hub Stroke: 62.00 mm


• Clearance: 0.05 mm


• Compression Height: 25.00 mm


• Dome Volume: -7.40 cm³


• Compression Ratio: OEM (11.90:1)


• Theoretical Weight: Not specified

Cross-Reference OEM Part Numbers

• Piston: 8601DA


• Lock: CW20


• Pin: WP038


• Ring Set: 950XSY


• Rod: P4029


• Part No.: 56-W4865+00A.WO


• OEM Reference: 5TG-11631-12-00, 4865M09500

Vehicle Fitments

• Yamaha YFZ450 2004–2005