Sorry. I should have clarified. I'm going off the Mantaray style S-7 wheel size since it's specific to Schwinn and the 20 x 1 3/4 tire size. I've been told (and research also states) that Mantaray's were still made after 1972, but with the 20" S-7 wheel and forks but was renamed. Although the frame, chainguard, etc. stayed the same. Although I don't know which models they were or if this is entirely true.