Shaw, I actually rode a Ducati Desmo and it was pretty darn fast and the thing that I noticed was that there was no metallic noise from the engine. I think the design was a little different. I believe it used a second complimentary cam to pull the valve back to the seat. "J", it was great... The problem was that it was VERY expensive to build and did require some checking (valve train) and this is probably the reason it was not jumped on by the racing arena. You could get a valve spring engine to run just about as well for a lot less investment, but make no mistake about it, if it were a little cheaper to build, there would be a lot of racers running them.