Its always done by process of elimination. Holes in Lugs? Head badge holes? rear dropouts? Oil holes? Parts?You bought it from Spence Wolf and have the receipt? or its in Spence Wolfs register of bikes sold? In the case of trying to use the serial numbers to establish a range of bikes built in a particular year ,its very dodgy. Did Cinelli's in house builders do a whole frame or did they do Fork or rear triangle and someone else finished it off? I think they also used off site subcontractors . All in all I dont think anyone was really keeping track of what numbers were put on what frames. And even less so after a long lunch break and wine. I have a bike I think is maybe 1963 and I know the paint on it was repainted in 1971 or so . How? It belonged to Carol Kelly, Tim Kellys(former) wife and I remember it being redone for her.
BOB FREITAS MILL VALLEY, CA USA
who owns an early 60s bike repainted in the early 70s but still sporting its early 60s kit