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I read in CR your:
My questions are: 1. What is the quality of this frame? If Columbus tubing, which type? 2. The frame has a fair amount of rust around the lugs (chromed on headtube) and cable guides. Would a basic paint job be appropriate? Should I worry about new decals? I can't imagine that this is a collectible item. I just want a nice looking bike without shelling out too much money.
At Cyclart we have refinished about 10 of these frames over the years. West Coast Cycle, the importer and distributor of Centurian bikes had a short lived deal to distribute Cinelli products in the US. WCC expected to sell more frames than Cinelli could build, and had an excellent relationship with Japanese builders. Cinelli was offering a comprehensive line of frame lugs and frame components and it's new ownership, was thinking of the company more as a design company than a production house. So Cinelli designed it, and WC sold them. I'm not sure which Japanese builder constructed them. I am sure however, after refinishing many of these frames and speaking with owners who love them that the bikes are both well designed and constructed. I once had a discussion with at fellow who insisted that his Cinelli/Centurian was a pure Cinelli. I pointed out to him the design differences, (seat lug etc.) but especially that the frame was much lighter than a Cinelli of the same size. Cinelli frame so fte same era were not especially well made, the Centurian/Cinelli's I've seen were far better crafted than the "real" thing!.
Decals? If you like. Almost all to the Cinelli Centurian we've restored have opted for replacement decals to prevent the generic look. We have reproduced the original decals and also have made a version that inverts the emphasis on Centurian and Cinelli, which most people prefer, while not misrepresenting the bike as pure Cinelli.
I'm at home now, if you drop me an Email to firstname.lastname@example.org <mailto:email@example.com> , I'll try to send a link to photos of some of these bikes we have restored. I also have original ads I can copy.
Since your are on a budget, I'd suggest that we remove the rusty chrome and repaint only. We can do excellent new chrome, but it is costly. Paintwork can run from $150 to $450.
The frame is certainly Columbus SL .