The presence a Nuovo Valentino derailleur in conjunction with what appears to be a Sugino Super Maxy cotteless crankset would place this very, very late 1970s to very early 1980s. Bianchi models often varied from market to market. This one is reminescent of a Super Turismo but with a lower grade derailleur. Calibrati 1-20 is hi-tensile tubing. Given the era, the serial number could be on the front collar of the top head lug or both sides of the seat lug.

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