Originally Posted by
AlbertoDeSantis
Thank you all very much for taking the time to reply.
I had fun studying chromoly tubing thicknesses yesterday. Common bike tube thickness is 0.6mm or 0.7mm in the middle and 0.9mm at the ends.
The Brompton may be a straight tube, about 1mm thick. Just a wild guess.
A straight Hi-ten 1mm-thick wall pipe? That can't be right for the price and for its vaunted crafsmanship. Even my $250 Chinese-made FnHon Gust frameset is chrome-molybdenum steel and its main tube is butted. Something doesn't add up.