Wiseco 4721PS Forged Piston Standard Bore 3.498in 10.5:1 Compression Evo Sportster 1200

The Wiseco 4721PS is a high-performance forged piston designed for the Harley-Davidson Evolution Sportster 1200 and 1100 engines. Featuring a domed profile at a standard bore of 3.498 inches and a 10.5:1 compression ratio, this piston is purpose-built to deliver increased performance over the stock piston while maintaining reliability for street and performance riding applications.

Key Features:

• Forged from high-silicon aluminum alloy for superior strength, reduced weight, and improved heat transfer compared to cast pistons
• Standard bore: 3.498 in. with domed top for optimized compression
• 10.5:1 compression ratio for improved throttle response and power output
• 73 ci. (1200cc) displacement compatible design engineered specifically for the Evolution Sportster platform
• CNC diamond-turned finish ensures precise sizing and consistent fitment across all cylinder bore compositions — cast iron, chrome, Nikasil, and boron composite
• Machined valve pockets deeper and larger than stock, providing adequate clearance for most high-lift cams
• Compatible with 3497X ring set (sold separately)
• Designed for use with stock stroke flywheels only
• Engineered, forged, and machined in the USA in Mentor, OH

Each Wiseco piston kit includes the piston, rings, wrist pin, and circlips — everything needed for a complete piston replacement. This piston is part of the Wiseco V-Twin series, representing over 80 years of forging expertise applied specifically to each engine platform for optimized performance and durability.