Listmembers,
My computer (and therefore access to my email) was down for the past 6 days; I missed out on the Colnago Mexico/Columbus tubing debate which took a large amount of the 300 emails I came back to when I got connected again. Please don't shoot me if I fill in a few details that didn't seem to get resolved regarding Columbus Record and KL tubing.
First of all, a frame tube set includes 11 tubes (not 10 as Marc suggests), I sorry but the steerer tube is part of the tubeset, and a very important one at that. The 4/10 most deffinitely DOES NOT refer to 4 tubes of 10 in the frame. More likely tube thickness somewhere designitated in tenths of a MM; but there are no .4 thicknesses on any older Columbus tubes that I know of. BTW, the early Colnago Mexico frames were built with Columbus KL tubesets. The main tubes are .7, .5, .7. Each tenth of a MM is .004", so the .5mm section is .020" and the butted sections are .028". Technically a KL frame requires a 27.4 seat post and is recommended to be brazed with (low temp.) EasyFlow 45 silver brazing alloy.
Here are some little know facts about Columbus Record tubing that I have learned from having built several "personal" frames from the two variations of Columbus Record tubes.
First, the original "Record" tubeset that was used on the (two) hour record frames built for Eddy Merckx to use for the record were what Mario Confente called "Tre Decimi" (don't know the actual spelling) which meant .3MM. We had a few sets of it at Masi in Carlsbad and the story was that Columbus wouldn't sell it to just anyone. I got my hands on a few sets for personal use, and it was the genuine article. The main tubes were .3mm straight gauge (.012") and the chainstays and seat stays are .5mm (.020"). In 1977 I built a 50cm road frame out of that material, but on account of unusual circumstances I never got to ride it. (Richie, I'd still like to get that frame back from the person you sold it to if possible). The Record sets from Masi Carlsbad had undented chainstays, unlike the other sets I later aquired which did have indented chainstays. In about 1990 I built a "record attempt" track frame using the other .3mm Record tubeset from Masi; its the one in the picture Dale took that shows some caveman (looks like) holding a green colored track bike on his website under Baylis Cycles. I used every trick in the book on that frame for style and lightness and it is still one of my all time favorites.
The later version of Columbus Record tubing has main tubes .5mm thick and again straight gauge. The chainstays are .5mm so it's a light set, but not as exotic as the earlier stuff. One can quite easily pinch the tubes of the .3mm tubes and both see and feel the tube deflect. I built a 48cm road frame and a 47.5mm track frame from the .5mm material, the track frame having all three tubes 1 1/8" diameter (in other words oversized top tube) and .5mm chainstays. The kicker is that they were both designed for 650c wheels and therefore have relativly shorter stays and fork blades. The record tube is not suitable for road bikes, regardless of size I have found. My 650c track frame on the other hand is ideal. Damon Rynard (or however you spell his name) tested this frame on his deflection testing equipment when he was conducting tubing stiffness tests a few years ago. He found because of my comstruction methods and the shortness of the stays and small size of the main triangle that it's relative deflection compared to a standard frame 58cm size for 700c wheels with a straight gauge down tube (.035") of CrMo and Columbus SL TT and ST. Quite stiff for .5mm tubes! The rear triangle was even more shocking. The .5mm chainstays gave strength (stiffness) equal to Columbus SP chainstays on 700c wheels with chainstays 410mm in length. I was quite proud if those numbers, and I really dig that frame for track use. It is the track frame I'm riding in the photo that appears on my home page of my website at http://www.baylisenterprises.com
As several people mentioned, no production bikes are ever built using Columbus Record tubes. It's strictly for track record attenpts, even though I've experimented for my personal education, it's clear it shouldn't be used for anything else. I have one more Record tubeset that I aquired somewhat recently; but I'm not sure what will become of it. I'm thinking I will build a Nervex Pro lugged record attempt style track frame just to put it to good use. Too bad it won't be for sale! Hope this enlightens those interested in this topic without reopening the previous can of worms.
Brian(back amongst the living)Baylis
La Mesa, CA