S&S Cycle 129" Big Bore Power Package for M8 VVT Engines

Elevate your riding experience with the S&S Cycle 129" Big Bore Power Package, engineered to transform your 107" Milwaukee-Eight (M8) engine into a formidable 129" powerhouse. This bolt-on kit delivers a significant displacement increase without requiring any case machining, making it a straightforward yet revolutionary upgrade for your motorcycle.

Description

Unleash the full potential of your Harley-Davidson M8 engine with this comprehensive S&S Cycle 129" Big Bore Kit. Designed for a seamless upgrade, this power package takes your 107" M8 to 129" displacement, providing a substantial boost in horsepower and torque. The kit features robust 4.32" bore cylinders and high-performance 11.0:1 compression ratio forged pistons, ensuring exceptional durability and responsiveness. Central to this M8 129" Power Package is the advanced S&S oil pump/cam plate, distinguished by its striking blue anodized finish. This innovative design includes independent scavenge sections for both the flywheel cavity and cam chest, along with debris screens in both scavenge pickups and a magnet in the cam chest to prevent contaminants from reaching the oil pump. Enjoy increased oil flow capacity on both the feed and scavenge sides, complemented by an adjustable pressure relief valve that can be fine-tuned even with the unit installed. The kit also includes S&S Quickee pushrods, premium tappets, and hard-anodized, black-coated billet aluminum tappet cuffs for superior valvetrain stability. Optimized for big bore applications, the S&S 550 cams work in harmony with high-performance conical single wire valve springs that accommodate cam lifts up to 0.605". Proudly made in the USA, this bolt-on big bore kit is specifically designed to fit VVT (Variable Valve Timing) models, offering a complete and reliable engine upgrade solution.

Features & Highlights

• Effortless Power Upgrade: Transform your 107" M8 engine into a commanding 129" without complex case machining, ensuring a quicker, simpler installation and immediate performance gains.
• Optimized Oil System: Features an S&S oil pump/cam plate with a striking blue anodized finish, independent scavenge sections, debris screens, and a cam chest magnet for superior lubrication, filtration, and extended engine longevity.
• High-Performance Valvetrain: Includes S&S 550 cams specifically designed for big-bore applications, paired with premium valve springs supporting up to 0.605" lift for maximum power delivery and aggressive throttle response.
• Durable & Precision Engineered: Equipped with 4.32" bore cylinders, 11.0:1 compression forged pistons, Quickee pushrods, and billet aluminum tappet cuffs for exceptional reliability and consistent performance under demanding conditions.
• Adjustable & Serviceable Design: An adjustable pressure relief valve allows for fine-tuning even when installed, while removable passage plugs simplify servicing and maintenance.
• VVT Compatible: Specifically designed to integrate seamlessly with Variable Valve Timing (VVT) models, ensuring broad compatibility and optimal performance across a range of M8 engines.
• American Made Quality: Proudly manufactured in the USA, guaranteeing high standards of craftsmanship, durability, and a product you can trust for your motorcycle.

Technical Specifications

• Engine Displacement Increase: 107" M8 to 129"
• Cylinder Bore: 4.32"
• Compression Ratio: 11.0:1
• Piston Type: Forged
• Cam Profile: S&S 550
• Valve Spring Compatibility: Cams up to 0.605" lift
• Oil Pump/Cam Plate Finish: Blue Anodized
• Tappet Cuffs Material: Billet Aluminum, Hard-anodized black coated
• Manufacturing Origin: Made in the USA
• EAN: 09040206

Important to Know

• Will fit VVT models.
• Not for any Trike models.
• Intake/rocker cover gaskets not included.