Nishiki introduced the mid-level Semi-Pro under the American Eagle marque in the late 1960s, quickly supplementing it with the low-end Custom Sport, which competed directly with the Varsity. By 1972 they had five models: Custom Sport; Olympic (adds QR); Kokusai (adds aluminum rims and cranks and straight-gauge CrMo main triangle); Semi-Pro/Competition (adds double-butted main triangle, Mighty Compe cranks); and Road Compe (tubulars, full CrMo frameset). Yours looks like something from the late 1970s.
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"Far and away the best prize that life offers is the chance to work hard at work worth doing." --Theodore Roosevelt
Capo: 1959 Modell Campagnolo, S/N 40324; 1960 Sieger (2), S/N 42624, 42597
Carlton: 1962 Franco Suisse, S/N K7911
Peugeot: 1970 UO-8, S/N 0010468
Bianchi: 1982 Campione d'Italia, S/N 1.M9914
Schwinn: 1988 Project KOM-10, S/N F804069