Engines and Components› Pistons and Piston Rings

United Engine & Machine Co

8499 HARLEYDAVIDSON EVOLUTION 80CI/1340L OS .010 PISTON SET

$94.97

SKU: U00B KB258.010

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Description

The United Engine & Machine Co KB258.010 is a piston and piston ring kit designed for Big Twin Evolution engines from 1984-1999. These pistons are made from a hypereutectic alloy, a cast material with 16% silicon content, known for its low thermal expansion rate, allowing for tighter piston-to-cylinder clearance. This kit is perfect for air-cooled engines.

Fitment

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Specifications

BrandUnited Engine & Machine Co
Part NumberU00B KB258.010

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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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