Just curious, where is standover height measured on a frame with a sloping top tube? Many of the cross frames appear to be too tall for me. I'm thinking of building up a cross bike but the geometries of many frames I have looked at don't compare at all to my classic frame roadie, not that I expected them to. My 49cm roadie fits perfectly but I imagine that I would want a bit more clearance for racing purposes. Thanks for helping.