A Brief History of the Marque
The first Italian scooter, the machine was built from 1949 to 1953 by San Cristoforo of Milan using a two-stroke engine of 98 cc in a tubular frame, initially built by Gianca of Monza. The Nibbio - meaning "Kite" in English - was designed by Scarpa, who also designed the Iso scooter.
In 1949 manufacture passed to San Cristoforo who developed a new two-stroke 125cc engine with disc valves.
In 1952, further modified, it was rebranded Simonetta.
Sources: MC Storico Conti, moto-collection.org, et al.