The Wossner 8666DA forged piston kit with a 77.00mm bore is designed for Suzuki RM-Z250 models from 2007 to 2009. Manufactured in Germany, this piston delivers excellent durability, heat transfer, and performance. Its elliptical design ensures even bearing contact under heat expansion, reducing stress points and preventing piston collapse.

Features

• Forged piston construction for enhanced strength and reliability


• Designed to optimize heat transfer from combustion chamber to cylinder walls


• Elliptical shape provides uniform pressure distribution during thermal expansion


• Reduces risk of localized pressure and piston failure


• Manufactured in Germany

Specifications

• Bore: 77.00 mm


• Actual Bore Diameter: 76.96 mm


• Display: 249 cm³


• Hub Stroke: 53.60 mm


• Clearance: 0.04 mm


• Compression Height: 19.60 mm


• Dome Volume: -3.30 cm³


• Wossner Compression Ratio: OEM


• OEM Compression Ratio: 13.40:1

Cross-Reference OEM Part Numbers

• Piston: 8666DA


• Lock: CW16


• Pin: WP070


• Ring Set: 770XAS-2


• Rod: P4004


• Main Bearing: 2 x MB830046


• Part No.: 56-W4921.A.WO


• OEM Reference: 12111-10H20-0F0, 4921M07700

Vehicle Fitments

• Suzuki RM-Z250 2007–2009