Wiseco PK1030 76mm Top End Piston Kit with Gaskets for Honda TRX300EX

The Wiseco PK1030 is a complete top-end piston kit engineered specifically for the Honda TRX300EX ATV. Featuring a 76.00mm bore and 11:1 compression ratio, this kit delivers a significant displacement increase over the standard 74.00mm bore, making it a popular choice for performance builds and top-end rebuilds.

Kit Includes:

• 1x Forged piston (76.00mm / Wiseco forging code 4574M)
• Matched piston ring set
• Wrist pin (chrome-plated for reduced friction)
• 2x Circlips
• Top-end gasket kit (Wiseco W5463)

Key Features:

• USA-forged construction — engineered, forged, and machined at Wiseco's facility in Mentor, OH
• Dedicated forging designed specifically for this 4-stroke powersports engine application
• Optimized strength-to-weight ratio — condensed grain structure aligned to part geometry for superior mechanical properties
• Armor Glide skirt coating for reduced friction and scuff resistance
• Horizontal slot pin oiling and pressure seal groove for maximum ring seal
• Race-ready dome finish with smooth edges for improved combustion flow
• Built to tighter tolerances than cast alternatives for enhanced performance and service life

Wiseco forged pistons outperform cast pistons in high-stress ATV applications by offering superior impact and fatigue resistance. Unlike brittle cast pistons, Wiseco forgings are designed to handle extreme conditions without catastrophic failure. Note: Cylinder boring is required when installing an oversized piston. All kits cover a single cylinder.