To avoid confusion or perhaps to create more. I think I should clarify my last post on this thread. I mistakenly claimed the internal diameter of the downtube was 1 inch.
Having discovered that this seat post is the only one suitable for my latest outings on
Ebay, I realised that I had taken a measurement of 1 inch and 1/16 or 27mm or as nearly as I can make out, using some fairly basic calipers.
Great isn't it two bikes acquired, neither of which had a safe or usable seat post. The one having been packed out with brown wrapping tape and the other being bent and too short!
All in all though, I don't think I've done too badly. Probably have to start a new thread on the non identical twins.
Thanks Tyred, Compo for your responses they have been thought provoking and are appreciated.
BTW just looking again at Compo's link to Sheldon's acticle and thinking 68mm BB shell was present before dumping it, perhaps this bike was threaded to 24 TPI after all and may therefore not have been made in Nottingham, despite the head badges suggestion.