PISTON KIT 01-04 YZF250 77.00, FORGED WOSSNER 8559DA 3-RING, 5NL-11631-10-00

Wossner forged piston kit designed for Yamaha YZ250F and WR250F models, featuring a 77mm bore and 76.95mm size with a three-ring design. Manufactured in Germany, this piston is engineered to enhance heat transfer, ensuring uniform expansion and even thrust load distribution. The elliptical design prevents localized pressure and piston collapse, making it ideal for high-performance applications.

Features

• High-strength forged piston for durability
• Optimized heat transfer for improved combustion efficiency
• Elliptical design to ensure uniform expansion and reduced localized pressure
• Three-ring design for enhanced sealing and performance
• Manufactured in Germany

Specifications

• Bore: 77mm
• Size: 76.95mm
• Part Number: 8559DA
• Compression Ratio: OEM
• OEM Compression Ratio: 12.50:1
• Lock Part Number: CW16
• Pin Part Number: WP059
• Ring Set Part Number: 770XAS
• Displacement: 249 cm³
• Stroke: 53.6mm
• Clearance: 0.04mm
• Dome Volume: -4.70 cm³
• Compression Height: 22.20mm
• Theoretical Weight: Not specified

Cross-Reference OEM Part Numbers

• 5NL-11631-10-00

Vehicle Fitments

• Yamaha YZ250F (2001-2004)
• Yamaha WR250F (2001-2004)