Re: MYSTERIOUS BIKE FRAME HELP? is it a SCHWINN?
I'm pretty sure that was homemade too. The way the forward seat tube goes through the head tube of the more-complete frame behind it, and just the overall way it seems to be joined together, seems to say "scratch build". That's not to say this is a bad thing. If the welds are good and sound and the frame isn't rusted through anywhere, it can still be okay. I do wonder, however, if proper rake-and-trail were taken into account when the front section of the frame was mounted to the middle. Long tandem bikes tend to not corner quite as well as regular single-seat bikes. Being short on trail would make it a real bear to deal with.
"There is nothing wrong with wanting a motorbike that is an extension of your personal taste and fashion sense; if you must ride somewhere, I say do it with style