PISTON KIT 05-07 YZF250 77mm WOSSNER 8614DA 3-RING

Wossner forged piston kit with a 77mm bore, designed for Yamaha WR250F, YZ250F, and Gas Gas EC250F models. This three-ring piston is engineered for optimal combustion chamber heat transfer and uniform bearing surface under heat expansion, reducing localized pressure and piston collapse. Manufactured in Germany for durability and precision.

Features

• Forged piston for superior strength and design
• Three-ring design for enhanced sealing and durability
• Optimized heat transfer to cylinder walls
• Elliptical design for uniform bearing surface and even thrust load distribution
• Manufactured in Germany

Specifications

• Bore: 77mm
• Standard size piston (PN# 8614DA)
• Lock Part Number: CW16
• Pin Part Number: WP070
• Ring Set Part Number: 770XAS
• Displacement: 249 cm³
• Stroke: 53.6mm
• Clearance: 0.04mm
• Wossner Compression Ratio: OEM
• OEM Compression Ratio: 12.50:1
• Dome Volume: -4.50 cm³
• Compression Height: 22.20mm

Cross-Reference OEM Part Numbers

• 5NL-11631-20-00

Vehicle Fitments

• Yamaha WR250F (2005-2007)
• Yamaha YZ250F (2005-2007)
• Gas Gas EC250F (2010-2015)

Majority of our listings are for a direct replacement for your original part.

Our parts are made of quality and are designed to meet or exceed the original OEM Standards.

Our products are often a cost effective alternative to genuine OEM Parts.

Please note: the models of bike we state in our listings are for general guidance only. Please make sure this item will fit your bike before purchasing. Also, we cannot guarantee fitment to any non-UK models.