
S&S CYCLE 128" Power Package Engine Performance Kit
In stock items will be shipped within 1-3 days.
You can return the products within 14 days for a full refund, check our returns policy.
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In stock items will be shipped within 1-3 days.
You can return the products within 14 days for a full refund, check our returns policy.
Enhance your Harley-Davidson's performance with the 128" Power Package Engine Performance Kit. This kit includes a Big Bore Kit that increases the displacement from 114"/117" to 128" without the need for case machining. Featuring 4-1/4" bore cylinders equipped with 11:1 forged pistons, it ensures optimal power delivery.
The S&S oil pump and cam plate with a blue anodized finish provide reliable oil flow, while the removable passage plugs allow for easy servicing. With independent scavenge sections for the flywheel cavity and cam chest, along with debris screens in both pickups, this kit enhances engine longevity.
Included are adjustable pushrods, S&S premium tappets, and hard-anodized tappet cuffs to improve stability in high-lift, high-rpm situations. The S&S 550 cams are designed specifically for big bore applications, complemented by S&S valve springs that support lifts up to .605".
All necessary gaskets, bearings, and hardware for a bolt-on installation are included, making this kit a complete solution for your engine upgrade. Proudly made in the U.S.A.
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If your order is delayed or arrives damaged, you must notify us within 14 calendar days. We will investigate the issue and offer a resolution in accordance with applicable consumer protection laws.
In accordance with Royal Legislative Decree 1/2007 (Ley de Defensa de los Consumidores y Usuarios), you have the right to withdraw from your purchase within 14 calendar days from the date of receipt, without giving any reason.
To exercise this right, contact us via email or through our website, providing your order number and contact details.
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