... I gave in to temptation and bought an old Bickerton yesterday!
Not sure of its age, it has a Sachs 3-speed hub and the American-style brace on the handlebar. A little tatty but complete and technically OK. Seller threw in an extra frame with headset, chainset, front and rear wheels with tyres, and a bunch of inner tubes.
A quite astonishing construction and feather light. Folds down as small as a Brommie in about ninety minutes... The kickstand (or kickwire?) in particular is a masterpiece of minimalist lightweight engineering.
The grand old Union ratrap pedals are non-folding, so short of carrying a spanner I think I will need to replace these.
Any ideas for a sympathetic restoration/tuning gratefully received. I will be changing the saddle (maybe to a B17?) and it will need battery lights (strictly speaking verboten here but I'll risk it) in a suitable style.