S&S Cycle 4.250" Big Bore Cylinder & Piston Kit - Wrinkle Black for Harley Milwaukee-Eight

Upgrade your 2017 and newer Milwaukee-Eight engine with the S&S Cycle 4.250" Big Bore Cylinder and Piston Kit. This bolt-on kit is engineered to increase displacement, delivering substantial gains in both horsepower and torque for your Harley-Davidson.

Why riders pick this

• Bolt-on design for 2017+ Milwaukee-Eight engines
• Increases displacement for more horsepower and torque
• Features a 4.250-inch bore for significant power gains
• Wrinkle black finish matches factory engine aesthetics
• Designed for stock or modified M8 platforms

Designed for riders chasing serious power, this S&S Cycle big bore kit transforms your M8 without requiring complex engine modifications. The 4.250-inch bore cylinders and matching pistons are ready to install, providing a significant boost whether your M8 is stock or already modified.

Unlock More Usable Power

• Bolt-on design for a straightforward installation on Milwaukee-Eight engines
• Increases engine displacement for enhanced horsepower and torque
• Durable wrinkle black finish blends seamlessly with factory components
• Engineered for 2017 and newer Harley-Davidson M8 models

Performance Ready for the Road

This big bore kit is an ideal foundation for a performance build, or as a standalone upgrade to uncork a detuned factory Milwaukee-Eight. While the installation is a bolt-on process, optimizing your engine's performance will require a proper dyno tune to ensure peak power and reliability after increasing displacement.

Specifications

• Brand: S&S Cycle
• Manufacturer Part #: 910-0683A
• Bore Size: 4.250 inch
• Finish: Wrinkle black
• Weight: 24.85 lb
• Category: Engine Components / Piston Sets - Powersports

Common questions