K' Tesh,
Have you looked at Worksman folders? They are heavy and very old school. They are still made in the US with what they describe as industrial strength steel.Like an old Schwinn. They may be right for you. The recommended folder weight is up to 250 pounds. Perhaps you could get a stronger rear wheel/hub.The website says they specialize in bikes for riders over 250 pounds. Though, I do not know if that includes the folders.The reference in one of the posts to the Raleigh 20 made me think of them. http://worksmancycles.com/shopsite_s...ml/page21.html Good luck in obtaining your TESOL degree.