# Why did the "Normal" valve win? Poppet valves vs. Sleeve Valves vs. Rotary valves.

Page: https://stenobird.com/podcast/cycle-world-podcast-6850183/why-did-the-normal-valve-win-poppet-valves-vs-sleeve-valves-vs-rotary-valves
Text version: https://stenobird.com/podcast/cycle-world-podcast-6850183/why-did-the-normal-valve-win-poppet-valves-vs-sleeve-valves-vs-rotary-valves.md
Podcast: [Cycle World Podcast](https://stenobird.com/podcast/cycle-world-podcast-6850183)
Published: 2026-02-25T17:02:32+00:00
Episode link: https://podcasters.spotify.com/pod/show/cycle-world/episodes/Why-did-the-Normal-valve-win--Poppet-valves-vs--Sleeve-Valves-vs--Rotary-valves-e3fjn3h
Audio file: https://anchor.fm/s/f21971c8/podcast/play/116038193/https%3A%2F%2Fd3ctxlq1ktw2nl.cloudfront.net%2Fstaging%2F2026-1-25%2F418815023-44100-2-7873200812ead.mp3
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Duration seconds: 4166

## Resource

There have been many engine valve designs since the dawn of the internal combustion engine. What made poppet valves stick? (See what we did?) There were many other designs and some, like the sleeve valve in the Bristol Centaurus WWII radial aircraft engine, that worked very well. Classic Kevin Cameron stuff here as he and Mark Hoyer discuss the relative merits of engine valve types.

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## Transcript

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