Desmodromic valve drive was often justified by claims that springs could not close valves reliably. There was once a time when Desmodromic valve technology was cutting edge and a necessary competitive advantage for Ducati in racing. Ducatisti around the world know that the red bikes have desmo valves. Not all of them can tell you what that means, exactly. The Greek words.

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By using our site, you acknowledge that you have read and understand our Cookie VlvePrivacy Policyand our Terms of Service. Ducati’s use a unique method to open and close their valves. It’s called the desmodromic valve train. The desmodromic valve system does not use springs to close the valve, it uses the cam and has a valve closing lobe.

Why did Ducati use this type of valve mechanism as opposed to a more tradition under the bucket shim design? Maintenance and servicing intervals. Mercedes Benz didn’t drop the idea of the desmodromic valve actuation because it performed better in ways that made the additional complexities worthwhile. The desmodromic valve actuation system that Ducati have some patents for is considerably different than the first desmodromic valve actuation systems that were invented and aforementioned.

Why things are the way they are: Desmodromic valves – RevZilla

Rotary valves – when correctly implemented – are a far better idea than currently working desmodromic valve actuation and also other popular Valvetrain systems; that lost popularity and funding for to F1 and other decisions. Theoretically this rotary valve approach resolves many limitations of the poppet valve whilst also offering many other benefits.


It still requires springs to be implemented properly and reliably; defeating one of its most commonly considered benefits. Finally, I believe it is mostly for reasons of tradition, heritage, and marketing, that Ducati persist with their desmodromic system on their non MotoGP machines; as it provides very little real-world benefits in those guises.

Given the metallurgy of the day it required a lot of spring pressure to ensure that the spring was push the valve closed. The desmo unit mechanically forces the valve closed as opposed to using spring pressure.

Desmodromic valve

This would allow an engine to run at a higher rpm then a unit with a conventional spring poppet valve. By clicking “Post Your Answer”, you acknowledge that you have read our updated terms of serviceprivacy policy and cookie policyand that your dexmodromic use of the website is subject to these policies. Home Questions Tags Users Unanswered. Why did Ducati decide to use the desmodromic valve train rather than a more tradition valve train?

What are the benefits to removing valve springs from the valve train? There’s a bunch of controversy about it’s use in wider applications so I took vlve link out. Just inserted it to make it simple for people like me to look up what desmodromic valvetrain is. I know your desmldromic trying to contribute!

Why things are the way they are: Desmodromic valves

Ducati use desmodromic valve systems because it provides for; A more faithful adherence to both; 1A Not just high speed Valvetrain timing. An alternative to pneumatic Valvetrain design approaches used by other manufacturers in MotoGP; that – if implemented correctly – can also provide both weight savings and also cylinder head port geometry benefits.


Jim Stanley 3. Happy New Year and cheers! You should have enough rep to comment now: OK thanks for that. If you register a user account in the system it may be easier for you to consistently sign in with the same user account so you gain reputation on a single account. It will help your reputation score that, as it increases, allows access to various features of the site.

D Cheers and Happy New Year. I agree that part of why they continue to use it is nostalgia and that the Ducatisti drive the loyalty to the mechanism, much like HD owners and their special V-Twins. The goal was to prevent valve float at higher rpms. This was more important on racing motors but Ducati used it desmodromuc street bikes as well. It also frees up frictional losses you see with typical valve spring design. I’d like to add that other motorcycle makers who race on Moto GP desmodrojic use a conventional valvetrain and most later switched to a pneumatic one en.

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