Somebody's going to correct me on this one but this is what I think I know?!.... We're talking about the four lugs on the front downtubes which support the dynamo-engine plates. Nearly all A7 / A10 frames have the two top lugs made out of castings which are slid onto the tubes and brazed on, but the bottom lugs are plain tubes welded onto the downtubes. Towards the end of the production run BSA started manufacturing frames where all four lugs were of the cast type. Some of these frames may have been used as general production frames at the very end of the production run on Super Rockets. All RGS frames were like this so the 'four lug frame' (should be four cast lug) suddenly becomes highly desirable to those who wish to build RGS copies. I am also aware that BSA sold these frames as replacement frames to dealers and individuals who had crashed or twisted frames. Some of these frames had both types of rear brake cable anchors, some had the sports footrest lugs mounted on the pillion loops, but this doesn't mean they are RGS frames which, to the best of my knowledge, are the only frames stamped with the 'GA10...' prefix. The replacement frames which left the factory were unstamped. There are bound to be a few minor discrepencies and anomalies but i think, in general, what I'm offering as information is fairly accurate.
The bike on Ebay is described as 1958 yet the front brake looks like Ariel (56/57) and the four lug frame was not in production in 1958 (as far as I am aware) so this frame is probably one of the replacement frames I referred to earlier. I'd be very interested to know what the engine and frame numbers are.
