The Wossner 88mm Bore Piston Kit (Part No. 8702D300) is a high-performance forged piston designed for Honda TRX400EX and TRX400X models. Engineered for superior strength and heat transfer, it features an elliptical design to ensure uniform bearing surface expansion, reducing localized pressure and preventing piston collapse. Manufactured in Germany, this piston kit provides a compression ratio of 12.5:1 for enhanced 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: 88mm


• Actual Bore Diameter: 87.94mm


• Compression Ratio: 12.5:1


• OEM Compression Ratio: 10.0:1


• Displacement: 397cc


• Stroke: 70.00mm


• Clearance: 0.06mm


• Dome Volume: +8.40cm³


• Compression Height: 26.20mm

Cross-Reference OEM Part Numbers

• Lock P/N: CW20


• Pin P/N: WP052


• Ring Set P/N: 880XSY


• Rod P/N: P4021

Vehicle Fitments

• Honda TRX400EX (1999-2008)


• Honda TRX400X (2009-2012)