S&S Cycle 129" Power Package Big Bore Kit for M8
S&S Cycle 129" Power Package Big Bore Kit for M8
About this product
About this product
Elevate your Harley-Davidson M8 engine's performance with the S&S Cycle 129" Power Package, a premium big bore bolt-on kit engineered to transform your 107" M8 into a formidable 129" powerhouse. This complete kit delivers a significant displacement increase without requiring any complex case machining.
Description
The S&S Cycle 129" Power Package is the ultimate bolt-on solution for riders seeking a dramatic increase in power and torque from their 107" M8 engine. Featuring robust 4.32" bore cylinders paired with high-strength 11.0:1 compression ratio forged pistons, this kit ensures exceptional performance and durability. At its core is an S&S oil pump/cam plate, distinguished by its striking blue anodized finish, which significantly enhances oil flow capacity on both the feed and scavenge sides. This advanced oiling system includes independent scavenge sections for the flywheel cavity and cam chest, along with debris screens and a magnet to prevent contaminants from reaching the pump, ensuring long-term engine health. The adjustable pressure relief valve allows for fine-tuning even after installation. Complementing these components are S&S 550 cams, specifically designed for big bore applications, along with S&S valve springs capable of handling cam lifts up to 0.605". The kit also includes Quickee pushrods, premium tappets, and billet aluminum, hard-anodized black coated tappet cuffs, all contributing to a comprehensive, high-performance Harley-Davidson M8 engine upgrade.
Features & Highlights
- Effortless Bolt-On Installation: Upgrade your 107" M8 engine to a potent 129" displacement without the need for complex, time-consuming case machining, making installation straightforward.
- Superior Oiling System: Features an S&S oil pump/cam plate with a blue anodized finish, offering increased oil flow capacity and independent scavenge sections for optimal lubrication and engine longevity.
- Enhanced Engine Protection: Integrated debris screens in both scavenge pickups and a cam chest magnet actively prevent harmful contaminants from entering the oil pump, safeguarding critical engine components.
- High-Performance Camshafts and Valve Springs: Includes S&S 550 cams, specifically engineered for big bore applications, paired with conical single wire valve springs designed to support cam lifts up to 0.605".
- Premium Valvetrain Components: Equipped with Quickee pushrods, S&S premium tappets, and durable billet aluminum, hard-anodized black coated tappet cuffs for reliable, high-RPM operation.
- Complete Kit for Convenience: Comes with all necessary gaskets, bearings, and hardware, ensuring a hassle-free, comprehensive bolt-on installation right out of the box.
Important to Know
- Not for any Trike models.
Shipping & Return
Shipping & Return
Free shipping to GLS parcel shop parcel box for purchases over DKK 1,000.
GLS home delivery costs DKK 59.
We do our best to ship your order as quickly as possible. All orders are generally packed within 24 hours on weekdays.
There is a 14-day return policy. Read more
Specifications
310-1223C
Highlighted Fins, Wrinkle Black
Power Package
Performance Kit
4,320"
11,0:1
129"
4-3/8"
525 mm
315 mm
697 mm
Chain
Chrome Pushrod Tubes
Engine
Kit
Oil Cooled
Reviews


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