My memories of the bike boom were in the early 70's, around '72 and '73 when oil prices soared. The market was flooded with all sorts of bikes, a lot of them lower end European types with high tensile frames, steel cranks, steel rims, etc. Schwinn started the LeTour about that time, and some of the Japanese imports were nicer than the European stuff.
That boom faded away later in the decade. "Breaking Away" came out in '79 or so, after the first bike boom.