I think the sweet spot is somewhere between the GS500 and the 650, but I'm not sure. This CB500, geared lower, with a bit more juice, could be pretty sweet!
Changed my mind. Can't do it. Rode the GF's '81 CX500 last night to blow the carbon out before winter, and 50hp just won't cut it. I hopped on my FZ6 afterward and about put it in a hedge. Then romped home on the freeway at an effortless 80mph.