My Opinion The Sharpest Mechanic Who Ever Lived...

JoeH wrote:

MEXICOWANDERER wrote:
Another neat concept is desmodromic.

Camshaft lobe operated valve closure. No springs. No float. No tons of resistance against engine revolving.

Smokey taught me the TRUE way to audit energy at age ten. The TRUE way of auditing production costs. The TRUE way of analyzing pros and cons of anything mechanical. He is held sixty-two years later on a personal pedestal of awe.

Ducati motorcycles have had desmodromic valves for a long time -- since the late 50's .

true, but the racing engines were a complete desmo engine, no valve springs of any kind. usually needed bump starting since valves wouldn't completely close at starting rpm with valve clearance set properly. The street bikes desmo engine use (or at least till a few years ago) a set of very light springs on intake and exhaust to make sure the valves close completely making it easier to start and better low rpm performance.

Mercedes also used desmo engines on some of their racing engines. But I think Ducati is the only mfg to consistently use a desmo design on production engines.