I am guessing early "70's". But it ain't Gospel. Even here those early Zeus are extremely rare. If you're looking for replacement parts they show up on Spanish EBay occasionally. Prices can be very reasonable. I just bought a wheel set. Zeus Gean Sport front hub Gigante rear hub Mavic Montihery rims and a Regina Oro freewheel for 10 Euro. Ed Coin, Malaga Spain