Engines and Components Engines, Blocks and Components

S&S Cycle

S&S Cycle 79-84 BT 88in Sidewinder 3-5/8in Big Bore Cylinder Kit - Gloss Black

$1,995.95

SKU: S0GE 91-9001

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Description

Part #: 91-9001

Installing this 3-5/8" big bore kit will increase the displacement of stock 80" HD (R) shovelhead engines to 88" using the stock 4-1/4" flywheels. This may also be used to build an 88" engine in 74" shovelheads if a 4-1/4" stroke flywheel assemble is also installed. The kit includes S&S 3-5/8" bore cylinders, 3-5/8" bore forged pistons with rings and wristpins, S&S stainless steel head bolts, base nuts, head gaskets, base gaskets, exhcaust gaskets, and instructions. Compression is 7.5:1. The cylinders are stock length so stock length pushrods and manifold may be used.

MIA's Description

The S&S Cycle 91-9001 Big Bore Kit increases the displacement of stock 80" Harley-Davidson Shovelhead engines to 88" using stock 4-1/4" flywheels. It includes 3-5/8" bore cylinders and forged pistons, along with gaskets and hardware for installation.

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Specifications

BrandS&S Cycle
Part NumberS0GE 91-9001

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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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