Engines and Components› Pistons and Piston Rings

S&S Cycle

98 Cubic Inch Piston Kit with 3.937" Bore

$879.95

SKU: 0910-4524

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Description

This kit allows you to convert an 88" Twin Cam engine to a 98" displacement when used with 4" stroke flywheels. The pistons are forged for durability and feature a 3.937" bore size with a standard oversize. The kit provides a 10.3:1 compression ratio when used with stock heads, offering increased power output without sacrificing torque. The installation process involves boring the stock cylinders to the nominal diameter with a clearance of +/- 0.0005" for optimal fit. The deck height for these pistons is 1.265". This kit is specifically for use on 1999-2006 Harley Twin Cam models equipped with S&S 98" big bore kits.

MIA's Description

It features a 3.937" bore size, 10.3:1 compression ratio, and a 4" stroke length, resulting in a 98 cubic inch displacement. This kit is compatible with stock rods and allows stock cylinders to be bored to accommodate the larger piston.

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Specifications

BrandS&S Cycle
Part Number0910-4524
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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