Neither of my 1970 or 71 catalogues state type of tubing used.bagpuss":3kf7sq11 said:Good way of finding out if it is 531.
Take frame to a good LBS. They should have a gauge to measure tubing size.It is a chamfered tube that goes inside the seat tube.This tube has sizes on it.
Bear in mind, double butted and plain gauge may well be different diameter.
twiz46":13m9xlo1 said:Ok thanks everyone seems its just a basic steel Carlton frame then, nothing to get excited about, on the upside I won't feel guilty if I turn it into a fixie then.
Sorry if it offends anyone.