Wiseco 4721P3 HD 1200 EVO Domed Forged Piston Kit 3.528 In. Bore 10.5:1 CR

The Wiseco 4721P3 is a forged V-Twin piston kit engineered specifically for the Harley-Davidson 1200 EVO engine platform. Featuring a domed piston design with a 3.527-inch (3527X) bore and a 10.5:1 compression ratio, this kit is built for riders seeking increased performance and durability over stock cast alternatives.

Key Features:

• USA-Made Forged Construction: Engineered, forged, and machined in Mentor, OH from aerospace-grade, high-silicon low-expansion aluminum alloy for superior strength, reduced weight, improved heat transfer, and longer service life
• Domed Piston Design: Optimized dome profile raises compression to 10.5:1 to maximize power output on the 1200 EVO engine platform
• Precision CNC Machining: Diamond-turned finish using CNC turning centers ensures consistent sizing and a perfect fit in cast iron, chrome, Nikasil, and boron composite cylinder bore compositions
• Oversize Bore Option: 3.527 in. (3527X) oversize bore extends cylinder life; compatible with cylinder resleeving for chrome, Nikasil, and boron composite cylinders
• Complete Kit: Includes piston, piston rings, wrist pin, and circlips — everything needed for a top-end rebuild
• Finite Element Engineered: Wiseco utilizes 3D design and finite element modeling software to optimize strength-to-weight ratio for each specific application

Wiseco's forging process compresses the aluminum alloy's molecular grain structure, producing a piston that is more resistant to impact and fatigue than cast alternatives — critical for high-compression, high-performance V-Twin builds. The 4721P3 is part of the Wiseco Forged 4-Stroke Series and is purpose-built for the HD 1200 EVO platform.