Gentelemen, good evening. I picked up a Schwinn Gateway on the curb today. This is the exact bike, except mine is missing the back wheel. The measurements on the tire say 700 x 38 cm, but from top to back w/ the tire inflated, it only measures 27 inches. The ones I found on the web list it as a 28 inch wheel, so I'm confused. I would love to make this rideable, but is missing a key piece w/ all the gears. Not much for sale our there w/ these measurements. What size is it? Is it restoreable? Should I switch it to a coaster brake bike? Thanks in advance...)