Size is a 23" (per catalog) or 58cm, measured center-to-top (of the top tube, NOT the top of the seat tube as so many erroneously do when selling bikes). Cannondale sold their tourers in 2" increments, 19" (at some point), 21", 23", 25" and for a few years, a 27". Their road/criterium (SR/SC) bikes were always in cm, measured the same way.

That Superbe Pro shifter lever (drive side) is not correctly oriented--likely, it's the typical Cannondale shifter boss mis-orientation (which is easily remedied). Maybe it was set up incorrectly, but I really think it's the shifter boss. I've dealt with this, as have many others.