There is a sloping top tube C50 up for bid on e-bay (listed as a 54 cm). The seller reports a 16.5 head tube length and virtual frame size as one that would fit a 5'9" person (as in 54 cm). The only size frame, sloping or traditional, I can find with a 16.5 head tube is 58 cm (top tube of 56.3). I don't want to end up with a too big frame set and have to hassle with the seller about shipping it back, etc. He insists it is a smaller size frame, referencing a frame chart for which he provides a link. This chart does not support a 16.5 head tube on a smaller (as in 54 cm) frame. For the record, I am 5'10" and a traditional Colnago 55 with a 54.3 top tube fits me perfectly. The head tube for a 55 is listed as 14.4 traditional and 13.3 sloping. Help! The bid is only open for 6 more hours.

If the frame is a 54 sloping it will fit like a traditional 58. Colago keeps most of the geometry the same on sloping/traditional frames while just lowering the seat tube collar by 4cm.

I saw the same frame on e-bay, and was thinking about bidding on it myself because a 54 traditional Colnago fits me. However, that headtube measurement is nowhere close to a 54 traditinal (i.e., 134mm). I would guess that it is a 54 sloping, which is way too big for me because I just bought a Cristallo that is a 50 sloping and I will be lowering the seatpost about an inch once I get the wheels for the bike. I am 5' 9" with a 31" inseam and the optimal frame size for me is a 51cm measured c-c or a 53 cm measured c-t like Colnago does. I want to get a 54 traditional as a repairable racing bike because it is very close to my Cristallo 50 sloping in geometry, which I do not want to wreck.

Thanks for your help J. Knight. You helped me to feel secure in not bidding. The auction is now over but I wouldn't be surprised to see it relisted due to misrepresentation. Frabrsroman, I think you did well in not bidding. For better or worse, I just closed a deal on a 2006 medium Look 585 frameset. I have owned both Colnago (still have the 20 year old Columbus steel frame hanging in my garage - beautiful in red with chrome fork) and Look (Reynolds 853). The Colnago was my first USCF bike and the Look was my second. I sold the Look but will never sell the Colnago. Maybe that is saying something. Thanks for the replies.