PISTON KIT YZF WRF 250 2-RING, WOSSNER 8713DB 08-13 77mm

Wossner forged piston kit with a 77.01mm bore and 76.97mm diameter, designed for Yamaha YZ250F and WR250F models. This 2-ring piston is engineered for high performance, featuring superior strength and design. Manufactured in Germany, it ensures optimal heat transfer to cylinder walls. Its elliptical design provides a uniform bearing surface under heat expansion, reducing localized pressure and evenly distributing thrust loads to prevent piston collapse.

Features

• Forged construction for superior strength
• Optimized heat transfer for efficient combustion
• Elliptical design for uniform load distribution
• 2-ring piston design for performance applications
• Increased compression ratio for improved power output
• Manufactured in Germany

Specifications

• Bore: 77.01mm
• Diameter: 76.97mm
• Display (cm³): 249
• Stroke (mm): 53.60
• Clearance (mm): 0.04
• Wossner Compression Ratio: 14.10:1
• OEM Compression Ratio: 13.50:1
• Dome Volume (cm³): -5.00
• Compression Height (mm): 22.50

Cross-Reference OEM Part Numbers

• Wossner Piston Yamaha YZ250F (PN# 8713DB)
• Lock P/N: CW16
• Pin P/N: WP059
• Ring Set P/N: 770XAS
• Rod P/N: P4005

Vehicle Fitments

• Yamaha YZ250F (2008-2013)
• Yamaha WR250F (2008-2013)