S&S Cycle 128" Power Package Big Bore Kit for Harley-Davidson M8
S&S Cycle 128" Power Package Big Bore Kit for Harley-Davidson M8
About this product
About this product
Transform your Harley-Davidson M8 engine with the S&S Cycle 128" Power Package big bore kit, designed to significantly boost displacement and power. This comprehensive kit upgrades 114" and 117" CVO models to a formidable 128" engine, delivering an exhilarating performance experience.
Description
Unleash the full potential of your Harley-Davidson M8 114" or 117" CVO engine with the S&S Cycle 128" Power Package, a premium performance kit engineered for a dramatic increase in power and torque. This bolt-in big bore kit is meticulously designed so that no case machining is required, simplifying the installation process and getting you back on the road faster. At its core are robust forged pistons, built to withstand the rigors of increased output and ensure long-term durability. With an impressive 4.250" bore and 4.500" stroke, this kit achieves a massive 128" displacement, complemented by an aggressive 11.1:1 compression ratio for explosive power delivery. The Power Package includes a complete suite of high-performance components: an upgraded oil pump/cam plate, Quickee pushrods with stylish chrome covers, precision tappets, tappet cuffs, a high-lift S&S 550 camshaft, and heavy-duty valve springs. The aesthetic is enhanced with a striking black granite finish featuring highlighted fins, ensuring your engine looks as good as it performs. This comprehensive performance upgrade is specifically tailored for 114" and 117" CVO models, providing a significant boost in engine displacement for an unparalleled riding experience.
Features & Highlights
- Effortless Bolt-In Installation: Designed as a direct bolt-in solution, this Power Package eliminates the need for complex case machining, significantly reducing installation time and costs.
- Massive 128" Displacement: Transform your 114" or 117" CVO M8 engine into a powerful 128" beast, delivering a substantial increase in horsepower and torque for thrilling acceleration.
- Durable Forged Pistons: Equipped with premium forged pistons, engineered for superior strength and resilience, ensuring reliable performance under extreme conditions and extended engine life.
- Comprehensive Performance Upgrade: Includes a full array of high-quality components such as an S&S 550 camshaft, upgraded oil pump/cam plate, Quickee pushrods with chrome covers, tappets, tappet cuffs, and heavy-duty valve springs for a complete system overhaul.
- Optimal Compression Ratio: Achieve maximum power output with an aggressive 11.1:1 compression ratio, providing crisp throttle response and exhilarating performance.
- Striking Black Granite Finish: The engine components feature a sleek black granite finish with highlighted fins, adding a custom, high-performance aesthetic to your motorcycle.
Technical Specifications
- Brand: S&S Cycle
- Product Name: Performance Kit
- Model: Power Package
- Part Number (MPN): 09040129
- Vendor Part Number: 310-1109C
- Units: Kit
- Bore Size: 4.250"
- Stroke Length: 4.500"
- Displacement: 128"
- Compression Ratio: 11.1:1
- Cooling System: Oil Cooled
- Cam Drive Type: Chain
- Color/Finish: Highlighted Fins, Black Granite
- Included Features: Quickee Pushrods w/Chrome Covers, Cam Chain Tensioner
Important to Know
- Not compatible with 121" CVO models.
- Not compatible with any Trike models.
- Intake/rocker cover gaskets are not included and must be purchased separately.
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
310-1109C
Highlighted Fins, Black Granite
Power Package
Performance Kit
4,250"
11,1:1
128"
4,500"
298.45 mm
490.855 mm
682.625 mm
Chain
Quickee Pushrods w/Chrome Covers, Cam Chain Tensioner
Kit
Oil Cooled
Reviews


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