[Dave at Pelican Parts]

I don't think I'd call it "typical", but it is certainly not unheard of to remove one of the fins. I forget if it's more usually the bottom head fin or the top cylinder fin--I would think the cylinder one, but I'm far from an expert in this...

I don't think it's common unless you're going for some interesting combination oof compression and deck-height, or you're using somewhat non-standard parts. (I.e., 96mm pistons designed for the 66mm stroke on a 2.0 motor with 71mm stroke.)

--DD