S&S Cycle 129" Power Package Big Bore Kit for M8

Unleash the full potential of your Harley-Davidson Milwaukee-Eight engine with the S&S Cycle 129" Power Package. This comprehensive big bore kit is engineered to transform your 107" M8 into a formidable 129" powerhouse, delivering a significant boost in torque and horsepower without the need for complex and costly case machining.

Description

The S&S Cycle 129" Power Package is a premium engine upgrade designed for motorcycle enthusiasts seeking unparalleled performance. This bolt-on kit features 4.32" bore cylinders and high-strength 11.0:1 compression ratio forged pistons, providing the foundation for extreme power gains. At its core, the package includes a meticulously engineered S&S oil pump and cam plate, finished with a distinctive blue anodized coating. This advanced oil management system boasts independent scavenge sections for both the flywheel cavity and cam chest, ensuring optimal lubrication and debris removal. Integral debris screens and a magnet in the cam chest further safeguard your engine's internals by preventing contaminants from entering the oil pump. Increased oil flow capacity on both the feed and scavenge sides, coupled with an adjustable pressure relief valve, guarantees consistent oil pressure and superior cooling for your oil-cooled M8 engine. The kit also integrates S&S Quickee pushrods, premium tappets, and durable hard-anodized, black coated billet aluminum tappet cuffs. Performance is further enhanced by S&S 550 cams, specifically designed for big bore applications, and high-performance conical single wire valve springs capable of handling cam lifts up to 0.605". Every component in this kit is crafted for durability and performance, ensuring a reliable and exhilarating ride. All necessary gaskets, bearings, and hardware are included for a straightforward bolt-on installation, making this 129" Power Package the ultimate Harley-Davidson M8 engine upgrade.

Features & Highlights

• Effortless Power Upgrade: Transform your 107" M8 engine into a potent 129" powerhouse with a bolt-on kit that requires no case machining, simplifying installation and saving time.
• Optimized Oil Management: Features an S&S oil pump/cam plate with independent scavenge sections, debris screens, and a cam chest magnet, ensuring superior lubrication and engine protection.
• High-Performance Internals: Includes 4.32" bore cylinders, 11.0:1 compression forged pistons, S&S Quickee pushrods, premium tappets, and billet aluminum tappet cuffs for robust and reliable operation.
• Big Bore Specific Cams: Equipped with S&S 550 cams precisely engineered for maximum performance in big bore applications, complemented by high-performance valve springs supporting up to 0.605" lift.
• Adjustable Oil Pressure Control: An adjustable pressure relief valve, serviceable even when installed, allows for fine-tuning of oil pressure to match specific engine demands.
• Complete Bolt-On Solution: Comes with all necessary gaskets, bearings, and hardware for a comprehensive and hassle-free installation, ensuring you have everything needed for the upgrade.

Technical Specifications

• Type: Engine Performance Kit
• Model: Power Package
• Units: Kit
• Product Name: Performance Kit
• Bore Size: 4.32"
• Displacement: 129"
• Compression Ratio: 11.0:1
• Stroke Length: 4-3/8"
• Cam Drive Type: Gear
• Cooling System: Oil Cooled
• Color/Finish: Highlighted Fins, Wrinkle Black
• Cam Lift Compatibility: Up to 0.605"
• Features: Chrome Pushrod Tubes
• Vendor Part Number: 310-1224C

Important to Know

• Not for any Trike models.