During the 80's the Japanese bike makers were using new technology to make bikes that laid the whoopin' on all others. Ducati was using its typical air cooled 90 degree V-twin like always, while the Jap bikes had water cooling, 4 cylinders, and 4 valved per cylinder (Ducatis had only 2).
But then, a new engine came into play, Ducati came out with a 851cc water cooled V-twin with 4 valves per cylinder, it also used their special "Desmodromic" valve system which closes the valves manualy with extra rockers to prevent valve float at high rpm. This new engine lead to many consecutive victories for ducati.

The first year the engine was used, they had to export a certain number of bikes t te US in order to run in the world championship. All the bikes sold were full blown race bikes producing nearly 120hp with full racing suspension and brakes.
17 years later i was lucky enough to get my hands on one of these :)