Originally Posted by
uncle uncle
No pictures, but when I rolled it into the shed this evening, I jotted down this number from the underside of the bottom bracket: C163316 (if I should add this to another thread for posterity, I will, just let me know). I had thought is was 1974 in year, "sports" category, model S-1, per the Miyata '74 catalog scan at the velo-pages. Let me know if you concur T-Mar (and thanks for the interest).
The C-code dates to 1974 manufacturer and it's a low enough S/N that it should be a 1974 model, so an S-1 (aka Racer) is the prime candidate.