Engines and Components› Pistons and Piston Rings

United Engine & Machine Co

9906 HARLEYDAVIDSON TWIN CAM/88 BIG BORE 107CI/1.74L OS .020 PISTON SET

$130.33

SKU: U00B KB912C.020

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Description

The United Engine & Machine Co. KB912C.020 is a forged piston designed for high-performance applications. It is constructed from 4032 alloy, known for its suitability in air-cooled engines, and features a dome with a 1.50 cc volume. This piston has a bore diameter of 4.145 inches and is designed for 1700cc engines.

This piston set is specifically engineered for 1999 to 2006 Harley-Davidson Twin Cam 88 Big Bore and 107ci engine configurations. It offers a compression ratio of 10.5:1 when used with an 85cc combustion chamber.

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Specifications

BrandUnited Engine & Machine Co
Part NumberU00B KB912C.020

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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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