Wiseco 4729P1 HD 1340 Shovelhead 7:1 CR Forged Piston Kit 3.507 in. Bore

The Wiseco 4729P1 is a forged high-performance piston kit designed for the Harley-Davidson 1340cc Shovelhead V-Twin engine. Built to a 7:1 compression ratio with a 3.507-inch bore (standard sizing), this piston delivers a reliable, low-compression rebuild ideal for longevity and mild performance applications.

Forged from high-silicon aluminum alloy, the 4729P1 offers superior strength and thermal stability compared to cast alternatives. Wiseco's precision forging process produces a denser, tighter-grained piston structure that resists deformation under the heat and stress of combustion — a hallmark of Wiseco's V-Twin lineup developed over decades of powersports engineering.

Key Features:

• 3.507 in. bore — standard sizing designation (P1)
• 7:1 compression ratio — ideal for stock or mild rebuilds
• High-silicon forged aluminum alloy construction for maximum strength and dependability
• Optimized piston skirt design for improved horsepower and torque delivery
• Deep valve pockets machined to provide clearance for most modified or high-lift cam installations
• Kit includes: piston, rings, wrist pin, and circlips
• Recommended piston-to-cylinder wall clearance: .003"–.0035" (0.075mm–0.089mm)
• Oversize pistons require cylinder sleeving
• Made in the USA

Wiseco's 4-stroke V-Twin piston line is engineered specifically for each engine platform, ensuring a precise fit and consistent performance. The 4729 series is a well-established part family for the Harley-Davidson 1340cc Shovelhead platform, with piston-to-wall clearances validated in Wiseco's official installation documentation.