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S&S Sidewinder® Big Bore Cylinders

The S&S® Sidewinder® Big Bore Kits

S&S SidewinderWhen S&S introduced the now legendary big bore cylinders in the bicentennial year 1976, they were given the name Sidewinder®, after the rattlesnake on the Gadsden flag (shown below), used by the original 13 American colonies. Like the retiring rattlesnake, the Sidewinder cylinders looked pretty harmless, but when it counted, they delivered.

The Sidewinder kit was a ground breaking product that allowed almost any repair shop to build big inch high performance engines, without the expense and time needed to design and fabricate special parts. In addition these kits were complete, containing everything needed to finish the job.

So, the next time someone asks why S&S big bore cylinders are called Sidewinders, you’ll know!
gadsden flag

A 3-5/8" bore S&S Sidewinder® big bore kit is one of the most popular performance upgrades available for Harley-Davidson® Evolution® big twin and shovelhead engines. Sidewinder kits are also available for 1986- 2003 Sportster® models. In the days before complete large displacement, high performance engines were available Sidewinder kits were the only way to go. Today, installing a Sidewinder kit to increase the displacement of a stock engine is still a very popular and cost effective alternative to replacing the engine.

All S&S Sidewinder kits include 3-5/8" bore cylinders and pistons - fit and ready to install, along with head and base gaskets. Sidewinder top end kits are available to increase the displacement of 80 cubic inch shovel and Evolution big twin engines to 88 cubic inches using the stock 4-1/4" stroke flywheels. Complete Sidewinder kits also contain an S&S dynamically balanced flywheel assembly. Depending on the stroke of the S&S flywheels, displacements of 88, 93, 96, 98, or 103 cubic inches are available. Since Sidewinder kits are configured to order, many optional parts are available in addition to the basic kits. See your S&S dealer for details.

Note - Stock crankcases must be bored to accept the larger 35⁄8” bore Sidewinder cylinders. It is recommended that Sidewinder installation be done by an S&S dealer. S&S also offers factory installation through our remanufacturing program.

Sidewinder kits and factory installation are available through your local S&S dealer.

Sidewinder Big Bore Kit for Shovelhead

Sidewinder Big Bore Kit for Sportster®

Sidewinder Big Bore Kit for Evolution Big Twin

Sidewinder Big Bore Kit for Shovelhead Harley Davidson Sidewinder Big Bore Kit for Sportster Harley Davidson Sidewinder Big Bore Kit for Evolution Big Twin