S&S Cycle 1250cc Conversion Kit Black 10.3:1 for Sportster 86-21

Unleash the full potential of your Harley-Davidson Sportster with the high-performance S&S Cycle 1250cc conversion kit. Engineered to transform '86-'21 883cc and 1200cc Sportster models, this kit delivers a significant boost in displacement and power, providing an exhilarating riding experience.

Description

The S&S Cycle 1250cc conversion kit is meticulously designed to elevate your Sportster's engine performance without the need for extensive modifications. This comprehensive Sportster big bore kit converts your existing 883cc or 1200cc engine to a powerful 1250cc displacement. At its core are premium forged pistons, engineered with larger-than-stock valve pockets capable of accommodating up to 2.00" valves, allowing for future head upgrades and enhanced airflow. These pistons feature coated skirts for reduced friction and extended durability, along with a convenient measurement window and the iconic S&S logo. Installation is streamlined, as this kit requires no machining or rebalancing of your engine, making it a straightforward Harley-Davidson Sportster engine upgrade for experienced mechanics and DIY enthusiasts. The kit includes S&S 3-9/16" bore cylinders, MLS (Multi-Layer Steel) head, base, and exhaust gaskets for a reliable, leak-free seal, along with all necessary rings, wristpins, assembly lube, and detailed instructions. Proudly Made in the USA, this S&S Cycle kit ensures superior quality and a precise fit for a significant engine displacement increase, transforming your ride into a true powerhouse.

Features & Highlights

• Significant Displacement Increase: Converts 1986-2021 883cc and 1200cc Sportster models to a powerful 1250cc engine, dramatically boosting torque and horsepower.
• Premium Forged Pistons: Equipped with coated skirts for enhanced durability and reduced friction, featuring larger valve pockets to accept up to 2.00" valves for maximum performance potential.
• Hassle-Free Installation: Designed for direct bolt-on application, eliminating the need for complex machining or rebalancing of your engine.
• Complete Kit: Includes S&S 1250cc pistons, rings, wristpins, 3-9/16" bore cylinders, MLS (Multi-Layer Steel) head, base, and exhaust gaskets, plus assembly lube and instructions for a seamless upgrade.
• Durable Gasket Technology: Utilizes MLS (Multi-Layer Steel) gaskets for superior sealing, ensuring long-term reliability and performance.
• American Made Quality: Manufactured in the USA, guaranteeing top-tier materials and craftsmanship for your Sportster.

Technical Specifications

• Brand: S&S Cycle
• Displacement: 1250 cc
• Bore Size: 3-9/16"
• Piston Type: Forged with coated skirts
• Valve Pocket Compatibility: Accepts up to 2.00" valves
• Gasket Type: MLS (Multi-Layer Steel)
• Compression Ratio: 10.3:1 (Estimated)
• Color/Finish: Black
• Country of Origin: USA
• EAN: 09310526

Important to Know

• Will not work with Harley-Davidson XR1200 models.
• 883cc Sportster models will require the use of XL1200 cylinder heads to achieve correct compression ratios.
• For optimal performance, CNC head porting, performance cams, upgraded exhaust, and intake components are recommended (not included in kit).