PISTON KIT YFM YFB250 71.50 WOSSNER FORGED 8659D050

The Wossner 71.50mm Bore Piston Kit (Part No. 8659D050) is a high-performance forged piston designed for Yamaha YFM250 Timberwolf, YFB250 Bear Tracker, Bruin, and Big Bear models. Engineered for strength and durability, it optimizes heat transfer within the combustion chamber and features an elliptical design to ensure even load distribution, reducing localized pressure and preventing piston collapse. Manufactured in Germany, this piston maintains the OEM compression ratio for reliable engine performance.

Features

• High-strength forged piston construction
• Optimized heat transfer for improved combustion efficiency
• Elliptical design for even thrust load distribution
• Manufactured in Germany

Specifications

• Bore Size: 71.50mm
• Actual Bore Diameter: 71.44mm
• Compression Ratio: OEM
• OEM Compression Ratio: 9.50:1
• Displacement: 229cc
• Stroke: 58.00mm
• Clearance: 0.06mm
• Dome Volume: -4.70cm³
• Compression Height: 23.80mm
• Theoretical Weight: Not specified

Cross-Reference OEM Part Numbers

• Lock P/N: CW16
• Pin P/N: WP041
• Ring Set P/N: 715XDS

Vehicle Fitments

• Yamaha YFM250 Timberwolf (1990-2000)
• Yamaha YFB250 Bear Tracker (2000-2004)
• Yamaha Bruin (2005-2006)
• Yamaha Big Bear (2007-2009)

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.