Classic & Vintage - Identifying old Balloon Style Schwinn Frames

I am curious how you can tell the difference between a Schwinn Corvette, Phantom, Typhoon, Stingray, Racer, etc. If you only have the frame and there is no chain guard or anything else with a name on it, how can you tell what you have? Maybe I am missing the obvious, but this seems to boggle my mind a bit.

You can't tell. The serial number only tells you when the frame was built not even when it was assembled into a bike. There are differences in the frames and examples of this would a bike that came with a 3 speed hub would have a hole in the rear bridge and fork to mount brakes. Where the tire goes past the seat stays for example is wider on balloon tired cantilever frames than on middle weight cantilever frames. Tabs for the chain guards might be different as would tabs to mount tanks but as i first said you can't tell the difference between a Jaguar vs Corvette vs 3 speed Tiger except by the paint. Schwinn was making bikes for kids not future collectable Mustangs or Corvettes so they did not care. Roger

Some of them have larger tires than the others. My 1948 Schwinn B6 is a heavy weight with 26x2.125 tires. Some are heavy weight bike and others are middle weight.

The drop-out is wider on the heavy weight bikes to accommodate the wider wheels. The heavy weight bike have an about 3" wide drop-out I beleive. I'm not sure how wide the middle weight bikes drop-out is.

Some of the frames were used on other models but there usually are some suttle differences. The early Schwinn Jaguar ('54-'55) bikes were considered heavyweight bikes with 26 x 2.125 tires. Then then went to the smaller tires and made it a middleweight bicycle.