Sure. XL1200 heads are 63-67cc depending on the head. 883 heads are 49cc.
But there's a couple downsides. Small diameter, long valves that take away piston to valve clearance is one of the big ones. They can be sunk, and they unshrouded, and bigger valves can be put in, but by the time you do that, the chambers start getting up there close to what a 1200 chamber is.