Thank you to everyone who responded to my verbose first post to this list. I am still reading and absorbing advice and information. Bring it on!! Charles Andrews commented on the seemingly random serial number dating system on Mark Petry's site. I found Marks site to be extremely informative and valueable, but I too was left without a clue as to when my bike was made, which is why I threw it out to the pack. I am not criticizing Marks site, so don't flame me. I get the impression that things around the Cinelli factory were relaxed when it came to serial numbers. They probably had more important things to do like ride bicycles. So I second the question; is there some rhyme or reason? Jay Sexton Sonoma County, CA