Originally Posted by
Glowgeek
Yep, extra valves and superchargers are the right stuff for power. I've read the Conley engines had mechanical issues eg cam gears and con rods. I'm sure those issues would have been worked out given enough time but hey, lesson learned, don't try selling a premium priced engines with mech issues. It only takes a few people posting legit complaints about a product to kill a product these days.
If I get lucky and find a nib YS 115S at a great price I'll pick one up to put in my Strega, otherwise it'll probably never see air time. "It's all or nothing baby!"
Part of the gain from using four valves, (and maybe most of it) is caused by the fact that two smaller columns of fuel and air accelerate quicker than one large one, toward the cylinder aiding cylinder filling which is a big plus.