Ducati Motor Holding S.p.A. is an Italian company that designs and manufactures motorcycles. Headquartered in Bologna, Italy, Ducati is owned by German automotive monopoly Audi through its Italian subsidiary Lamborghini.
Ducati is best known for high performance motorcycles characterized by large capacity four-stroke, 90° V-twin engines, with a desmodromic valve design. Ducati refers to this configuration as L-twin because one cylinder is vertical while the other is horizontal, making it look like a letter "L". Modern Ducatis remain among the dominant performance motorcycles available today partly because of the desmodromic valve design, which is nearing its 50th year of use.
Desmodromic valves are closed with a separate, dedicated cam lobe and lifter instead of the conventional valve springs used in most internal combustion engines in consumer vehicles. This allows the cams to have a more radical profile, thus opening and closing the valves more quickly without the risk of valve-float, which causes a loss of power that is likely when using a "passive" closing mechanism under the same conditions.