I got this frame for free just trying to figure out what it is. Started sanding it down it was all primer and rusty. Found out that it was a columbia bike from the head badge, it was painted over. So i looked up where i can find the serial number. Found out where to look some where in the back where the tires go. Found nothing! So got frustrated in sanding down and found nothing. So i jumped to the head badge and then i saw some numbers. So that what confusing me. I thought Schwinn only had the serial by the head badge. If any body can help me just want to no the year and what model it is. Thanks! Sorry don't know how to upload the pics. The head badge is a sticker and the serial number is going vertical.