S&s Cycle 128" M8 Big Bore Kit
S&s Cycle 128" M8 Big Bore Kit
About this product
About this product
Unleash the full potential of your Milwaukee-Eight engine with the S&S Cycle 128" Power Package Engine Performance Kit. This comprehensive kit delivers a significant power increase, transforming your 114" or 117" M-Eight into a fire-breathing 128 cubic inch powerhouse. Designed for bolt-on installation, this kit requires no case machining, making it an accessible upgrade for enthusiasts and professionals alike.
Description
The S&S Cycle 128" Big Bore Kit features 4.250" bore cylinders paired with high-compression 11.1:1 forged pistons, optimizing combustion efficiency for maximum power output. The kit includes an S&S oil pump and cam plate with a distinctive blue anodized finish, ensuring superior oil delivery and scavenging. Independent scavenge sections for the flywheel cavity and cam chest, along with debris screens and a cam chest magnet, provide enhanced oil cleanliness and engine protection. The increased oil flow capacity and adjustable pressure relief valve allows fine-tuning for optimal performance. S&S Quickee pushrods and premium tappets, combined with hard-anodized, black-coated tappet cuffs, enhance valve train stability at high RPMs. Paired with S&S 550 cams, these valve springs are designed to work with cams up to 0.605" lift, ensuring reliable high-performance operation.
Features & highlights
- Transforms 114"/117" M-Eight engines into a high-performance 128" powerhouse.
- No case machining required for easy bolt-on installation.
- High-compression 11.1:1 forged pistons maximize combustion efficiency.
- S&S oil pump and cam plate with independent scavenge sections ensure superior oil delivery and engine protection.
- Quickee pushrods and premium tappets enhance valve train stability.
- Includes all necessary gaskets, bearings, and hardware for a seamless installation.
- Proudly made in the U.S.A.
Technical specifications
- Brand: S&S Cycle
- Displacement: 128"
- Bore Size: 4.250"
- Stroke Length: 4.500"
- Compression Ratio: 11.1:1
- Cam Drive Type: Chain
- Cooling System: Oil Cooled, Water Cooled
- Type: Engine Performance Kit
- Color/Finish: Black Granite with Highlighted Fins
Important to know
This kit requires professional installation. All necessary gaskets, bearings, and hardware for bolt-on installation are included.
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
S&S CYCLE
310-1107B
Performance Kit
4,250"
11,1:1
128"
4,500"
Chain
Engine
Black
Kit
Oil Cooled, Water Cooled
Reviews


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