Wiseco PK1439 Compression ATV Piston Kit with Top-End Gasket Kit - 68.5mm 10.5 1

The Wiseco PK1439 is a complete top-end piston kit designed for the Honda TRX250EX Sportrax, featuring a 68.5mm bore and a high-performance 10.5:1 compression ratio. This kit delivers everything needed for a proper top-end rebuild, combining a precision-forged piston with a matched gasket set, high-performance ring set, alloy wrist pin, and circlips.

Forged for Superior Strength

Wiseco is the only aftermarket piston manufacturer in the United States that produces pistons exclusively through the forging process. Starting with aerospace-grade aluminum alloy, forging compresses and aligns the material's grain structure, resulting in a piston with greater density, improved tensile strength, and superior resistance to impact and fatigue compared to conventional cast pistons. Finite element modeling and 3D design techniques are used to optimize each piston for the highest strength-to-weight ratio possible.

Kit Contents:

• Forged aerospace-alloy piston — dedicated forging designed specifically for this application
• High-performance ring set — precision-matched for maximum compression and oil control
• Alloy wrist pin — lightweight and consistently true for reduced friction and durability
• Circlips — securing hardware included
• Top-end gasket kit — premium materials engineered to exceed OEM sealing standards

Key Features:

• 68.5mm bore diameter at 10.5:1 compression ratio
• Forged and CNC-machined in the USA at Wiseco's Mentor, Ohio facility
• Aerospace-grade aluminum alloy construction
• Optimized cam profile for peak horsepower and extended service life
• Race-proven design trusted by top-level race teams across all disciplines
• In-house dyno testing validates performance before release

Wiseco's complete top-end kits are engineered to simplify the rebuild process while delivering race-level performance and long-term reliability for ATV engines.