Engines and Components› Engines, Blocks and Components

S&S Cycle

124" Chain Drive Power Pack

$2,939.36

SKU: 310-1054

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In Stock
Ships by Sep 13
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$100 Minimum Order
30 Days Return
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Overview

The S&S Cycle 310-1054 is a 124″ Chain Drive Power Pack designed for 107″ Water-Cooled M8 Models.

This kit provides a big bore upgrade from 107″ to 124″ for a stock stroke flywheel. It features a wrinkle black finish with highlighted fins and a 4.250″ bore size with forged pistons and an 11:1 compression ratio. The power pack includes a precision-machined billet aluminum oil pump/cam plate with a blue anodized finish and a 550 cam designed for big bore applications with a chain drive.

Included components also feature Quickee pushrods, black pushrod tubes, S&S Precision Tappets, and tappet cuffs made from billet aluminum with a hard anodized black coating for improved stability. The high-performance conical single wire valve springs work well with cams up to .605 lift.
Show original supplier description
The S&S Cycle 310-1054 124″ Chain Drive Power Pack is a comprehensive big bore kit engineered to upgrade 107″ Water-Cooled M8 Harley-Davidson engines to 124 cubic inches while maintaining the stock stroke flywheel. This kit boasts a wrinkle black finish with highlighted fins, a 4.250″ bore, forged pistons, and an 11:1 compression ratio. The included oil pump and cam plate are precision-machined from billet aluminum with a blue anodized finish, featuring removable passage plugs, independent scavenge sections, debris screens, a magnet in the cam chest, and an adjustable pressure relief valve. The chain drive system utilizes an S&S High Performance cam chain tensioner. The package includes a 550 cam specifically designed for big bore applications and high-performance conical single wire valve springs rated for up to .605 lift. This kit is made in the USA. Installation of this power pack requires experienced mechanic knowledge, access to a factory service manual, and all necessary tools. Proper measurement of flywheel pinion shaft runout and end play is crucial, as excessive amounts will lead to damage, failure, and void the manufacturer's warranty. An aftermarket tuner, such as the ThunderMax Autotune System, is highly recommended for optimal performance. It is important to note that this kit is not recommended for Tri-Glide or other three-wheel models due to the lugging nature of these bikes.

Product descriptions are provided by our supplier partners and may not always be perfectly accurate. Not sure this fits? or call (760) 282-4645 and we’ll verify before you order.

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Specifications

BrandS&S Cycle
Part Number310-1054
CategoryEngines and Components

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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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Orders are processed in 1–3 business days. In stock parts ship promptly from our partner network. Special-order items either aren’t currently stocked or are built to your spec — expect 4–6 weeks. If a part goes on backorder while your order is in the queue, we’ll reach out and work through discounted alternatives together.

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