S&S Cycle M8 Big Bore Kit - 4.25" Bore - 128ci - 310-1108C

Transform your Harley-Davidson Milwaukee-Eight engine with the ultimate S&S Cycle 128" Big Bore Kit. This comprehensive Power Package is engineered to upgrade 114" and 117" CVO M8 engines to a formidable 128" displacement, delivering a significant boost in horsepower and torque for an exhilarating riding experience.

Description

Experience unparalleled performance with the S&S Cycle Power Package, meticulously designed to elevate your 114" or 117" Milwaukee-Eight engine to a commanding 128" displacement. This premium engine upgrade kit is a true bolt-in solution, eliminating the need for complex and costly case machining. At its core are robust 4.250" forged pistons, engineered for extreme durability and optimal power delivery. The kit boasts an impressive 11.1:1 compression ratio, ensuring explosive throttle response and increased efficiency. Designed for water-cooled models, this big bore kit includes a high-performance S&S 550 camshaft, an upgraded oil pump/cam plate, Quickee pushrods with stylish chrome covers, precision tappets, and heavy-duty valve springs. Every component works in harmony to provide a reliable and substantial power increase, making your Harley-Davidson M8 big bore conversion seamless and incredibly rewarding.

Features & Highlights

• Massive Displacement Upgrade: Converts your 114" or 117" Milwaukee-Eight engine to a powerful 128" displacement, dramatically increasing horsepower and torque for superior on-road performance.
• Effortless Bolt-In Installation: Engineered for convenience, this kit requires no case machining, allowing for a straightforward and quicker installation process.
• Premium Forged Piston Construction: Equipped with high-strength forged pistons, ensuring exceptional durability and reliability under demanding performance conditions.
• Comprehensive Engine Enhancement: Includes an S&S 550 camshaft, upgraded oil pump/cam plate, Quickee pushrods with chrome covers, tappets, and valve springs for a complete and integrated performance boost.
• Optimized Compression Ratio: Features an 11.1:1 compression ratio, providing crisp throttle response and improved combustion efficiency for a more dynamic ride.
• Sleek Aesthetic Finish: Components feature a black granite finish with highlighted fins, adding a custom, high-performance look to your engine.

Technical Specifications

• Product Name: Performance Kit
• Model: Power Package
• Vendor Part Number: 310-1108C
• Displacement: 128"
• Bore Size: 4.250"
• Stroke Length: 4.500"
• Compression Ratio: 11.1:1
• Cam Drive Type: Gear
• Cooling System: Water Cooled
• Color/Finish: Highlighted Fins, Black Granite
• Units: Kit

Important to Know

• Not compatible with 121" CVO models.
• Not compatible with any Trike models.
• Intake and rocker cover gaskets are not included and must be purchased separately.