Engines and Components› Engines, Blocks and Components

S&S Cycle

S&S Cycle 2017+ M8 129in Power Pack w/ Chrome Pushrod Tubes & Cam Chain Tensioner - Blk w/ Highlight

$3,359.95

SKU: S0GE 310-1223

In Stock
In Stock
Ships by Jun 17
Free Shipping
Non-Returnable Item
INSTALL DIFFICULTY
DIY PRO SHOP

Moderate — 2–4 hours

Description

This S&S Cycle kit upgrades 107" oil-cooled M8 engines to 129" without case machining. It includes big bore cylinders, matching cam, cam plate, oil pump, high-performance conical single-wire S&S valve springs, multi-layered steel (MLS) head gaskets, and a performance-matched 550 cam. It is designed for seamless compatibility with the stock crankcase and retains original engine serial numbers. Made in the USA.

Fitment

Fitment Guaranteed

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on fit.

Log your build in the MOTORMIA app and we’ll guarantee this part fits your exact setup — or your money back, return shipping covered.

Available on iOS & Android

Specifications

BrandS&S Cycle
Part NumberS0GE 310-1223

Videos

How to Install: S&S Cycle Power Package (Part 3) Dyno Runs

How to Install: S&S Cycle Power Package (Part 3) Dyno Runs
How to Install: S&S Cycle Winter Power Pack (Part 1) Big Bore Kit

How to Install: S&S Cycle Winter Power Pack (Part 1) Big Bore Kit
S&S 128 High Horsepower UPGRADE KIT By Moonshine Horsepower | Shop Talk Episode 59

S&S 128 High Horsepower UPGRADE KIT By Moonshine Horsepower | Shop Talk Episode 59
S&S Cycle Product Spotlight - Power Packages for HD® Twin Cam & M8 Models

S&S Cycle Product Spotlight - Power Packages for HD® Twin Cam & M8 Models
S&S Cycle Big Bore Kit for Milwaukee-Eight Overview

S&S Cycle Big Bore Kit for Milwaukee-Eight Overview
S&S 128 Big Bore / Harley-Davidson Lowrider S

S&S 128 Big Bore / Harley-Davidson Lowrider S
S&S Big Bore Kits and Cylinder Heads for Harley Review at RevZilla.com

S&S Big Bore Kits and Cylinder Heads for Harley Review at RevZilla.com

Buy with Confidence

Built for enthusiasts. Every order is backed by our 30 day return window on eligible items. Unused and uninstalled products may be returned with approved RMA and no restocking fees when received in new condition. Orders placed through the MOTORMIA app with a complete build qualify for our Fitment Guarantee — free return shipping if the part doesn’t fit your exact setup. The guarantee covers fit only; installation must follow manufacturer instructions, and we recommend a qualified shop for parts marked Difficulty 4–5.

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