Engines and Components› Pistons and Piston Rings

United Engine & Machine Co

4179 HARLEYDAVIDSON KNUCKLE/PAN/SHOVELHEAD 74CI/1200L OS .010 PISTON SET

$96.95

SKU: U00B KB263.010

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Description

The United Engine & Machine KB263.010 is a piston and ring kit designed for V-Twin engines. These pistons are constructed from a forged aluminum alloy (4032) with 16% silicon content. This high-silicon alloy offers excellent thermal barrier properties and a low rate of thermal expansion.

The piston style is a dome with two valve reliefs, allowing flexibility in installation. It features a bore of 3.447 inches, a stroke of 3.969 inches, and a rod length of 7.440 inches, with a compression distance of 1.805 inches and a dome height of 0.430 inches.

Fitment

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Specifications

BrandUnited Engine & Machine Co
Part NumberU00B KB263.010

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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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