Engines and Components› Pistons and Piston Rings

S&S Cycle

S&S Cycle 36-84 BT 3-1/2in +.010in 80in HC Forged Pistons

$410.95

SKU: S0GE 106-5520

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Description

Part #: 106-5520

These 3-1/2" +.010" bore high compression pistons fit 1979-'84 74" HD (R) big twin engines, producing 9:1 compression with stock unmodified cylinder heads.. The modern alloys used in these pistons, coupled with the advanced skirt profiles, allow them to be fit tighter resulting in low engine noise and long engine life. In the past, this could only be achieved with weaker cast pistons. S&S (R) will fit these pistons to your existing cylinders (when purchasing new cylinders, pistons can be fit to them as an option).

MIA's Description

This piston kit is designed for 80" stock big twin motors. It features forged pistons for superior strength and includes a set of pistons, rings, wristpins, and clips. The wrist pin deck height is 1.270". It is made in the U.S.A. This kit requires the use of connecting rods with a rod length of 7.440" (standard length OEM #24281-74A connecting rods). Using earlier connecting rods with a length of 7.470" (OEM #24281-41A) will slightly increase the compression ratio by about half a point and may cause clearance problems, so all piston-to-cylinder head clearances should be checked carefully if using early-style rods.

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Specifications

BrandS&S Cycle
Part NumberS0GE 106-5520

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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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