1250cc Big Bore Conversion Kits / '86-'22 Sportster

Revolutionize your Harley Sportster with the ultimate upgrade: the S&S Cycles 1250cc Conversion Kit. Tailored for the true enthusiast, this kit is your gateway to unmatched performance and the roar of real power. Featuring 10.3:1 flat top pistons, this comprehensive package ensures a seamless transformation of your ride into a formidable beast on the road. Kit Highlights: High-Performance Pistons: S&S 1250cc pistons with rings and wristpins, designed for peak performance. Precision Engineered Cylinders: S&S 3-9/16" bore cylinders for a significant boost in displacement and power. Enhanced Valve Compatibility: Forged pistons with enlarged valve pockets, accepting up to 2.00" valves for superior airflow. Quality and Durability: Forged pistons feature coated skirts with a measurement window and the iconic S&S logo, promising long-lasting performance. Comprehensive Gasket Set: Includes MLS head, base, and exhaust gaskets, ensuring a perfect seal and optimum reliabilit