Desmodromic is a term used to describe a specific valve operating system used in Ducati motorcycles. It refers to the valve actuation mechanism that controls the opening and closing of the engine's valves.
In a traditional internal combustion engine, the valves are typically opened by a camshaft, which uses a cam and follower mechanism to push the valves open. Springs are then used to close the valves when the camshaft rotation is completed. This setup is known as a "spring-loaded" valve system.
In this system, both the opening and closing of the valves are controlled by separate cams or lobes, eliminating the need for valve springs.
The Desmodromic system ensures that the valves are positively and directly actuated, allowing for more precise control over valve timing and reducing the risk of valve float at high engine speeds. This design characteristic is particularly beneficial for high-performance engines, as it allows for higher engine speeds and improved overall engine performance.
Ducati has a long-standing history of using Desmodromic valve systems in their motorcycles, and it has become one of their signature engineering features. It is often regarded as one of the contributing factors to Ducati's success in motorcycle racing, as the system allows for excellent engine performance and responsiveness.