I just bought a 1967 Schwinn Twinn 5 speed tandem on E-bay and need some input, as my wife and I are new to tandems. The bike was advertised as being in great condition, and suffice to say that it is something less than that. It does appear to be ridable, and if I am to keep it I would like to upgrade some components. I was attracted to the fact that the bike was made in my hometown (Chicago) and has the chrome fenders, etc. My wife and I will probably ride only casually (perhaps 10 - 20 miles per ride). Does it make any sense to put money into this bike (replace wheels, chain, drum brake assembly, etc) or would I be better off buying a new inexpensive tandem. I am told that parts are not available. Could I upgrade to modern day components? I am trying not to start off with a 2k investment. All help is appreciated.