I think we probably all agree that squish in a Commando engine is a desireable feature, but we shouldn't loose track of the fact that most Commandos, at least all the 850s, have no effective squish because the flat top piston is too far away from the head, due to the low CR, to provide effective squish. And they run fine that way. It's pretty easy to keep the piston-to-head clearance at .040" - .050", where the squish is effective, in a race bike. Typically, we push the piston as close to the head as we can for higher CR. But on a street bike, that's hard to do. When you dish the piston on something like a 1007 enough to get a streetable CR, but still keep .050" of squish, the penalty is a larger combustion chamber surface area, which is not what we aim for for efficient combustion. I really don't know if that's a good trade or not. What I do know is that a Commando engine will run just fine with no effective squish. I recently built an 883 Commando for the street, with a CR of 9.2, and way too much clearance for any squish effect, and it runs like a rocket. The factory short stroke 750s also worked quite well with a fully sphered head and no squish band. The Commando head design, mostly copied from the Gold Star according to some folks, creates enough swirl that you get enough turbulence at high rpm without needing more from the squish effect.
I'm not saying squish isn't a good thing, particularly for low speed performance. I'm just saying that a Commando will run fine without it.
Bottom line is, don't worry so much about squish, particularly in a 1007, which should provide massive low end torque just from the extra displacement.
As usual, just my humble opinion.
Ken
