On my CX bike I'm more upright.... and a bit further behind the cranks.
On the BJ, it's a bit more of a stretch for me, so I have the saddle a wee bit further forward.
Perhaps I was running too high a pressure? I was running 120psi on a 700 x 28 all condition sport tyre (60tpi).
PS The rims on the BJ are cheaper, and therefore heavier (but stiffer).