Please could someone shed a little light on this one for me. frame number is SB8085, not clear from pics or in person but a little pencil rubbing like we used to do over engravings as kids worked the trick in descerning it. I am more into vintage and actually came across this while chasing the owner's Golden Arrow, which is just out of my range. Anyway, I felt this was a good deal, knew a little (I mean only a little) about the SB prefix for the SBDU. Someone I know has been kind enough to help me identify what I have for the components but I am still missing the info on the frame. Also there is a tab/braze on hanging from the top tube, I think this has something to do with race specific cycles as opposed to custom collectors builds, is this right? Any ifo on this would be gratefully appreciated.