hope i dont burst your bubble, but its hard enough to find legit numbers of dry production bikes out there! i dont think many guys are weighing their conversion bikes with accurate scales.
but i'm in the same boat as you, i'd like to see how much the 500 engine weighs different than a 450f. but also keep in mind that fuel pumps, throttle bodies, and electronics are added weight on the 4 strokes that are in addition to the engine alone.
i'll get mine on some precision scales when i'm done with it for sure. HOPING on 215# range. that would be rad, we'll see.