Re: [Classicrendezvous] Mexico vs Super (was: Colnago quality)

Example: Framebuilding:Tony Beek

Date: Mon, 16 Oct 2000 19:28:10 -0400
From: gregparker1 <>
Subject: Re: [Classicrendezvous] Mexico vs Super (was: Colnago quality)
To: "" <>
Cc: gregparker1 <>, Marc Boral <>,


Thank you for the clarification that your original post was your opinion.

Greg Parker

P.S. The center section of a 753 top tube (early version) is about .017" thick (a little over 0.4 m.m.) and you can almost squeeze it by hand! I've heard stories of energetic people ripping shifter braze-ons right off of 753 downtubes into their hands by accident - big bummer!! I agree that 0.4 m.m. is right at the limit of usability with steel tubes of conventional diameters.... I still think that the early 753 is VERY cool for lighter riders, tho'

-------------Forwarded Message-----------------

From:, To: Marc Boral,

CC: ,

Date: 10/16/00 5:54 PM

RE: Re: [Classicrendezvous] Mexico vs Super (was: Colnago quality)


I'm not a frame builder and I don't play one on Television either, but after 25 years of looking at tubing spec's, "4/10" used in connection with a name of tubing sounds like the thickness dimension of the tubing wall to me.

Also, again I'm not an engineer, but 4/10 of a millimeter would be as thin as you'd ever want to go on a tube set. Actually probably thinner than you'd want to go if you're over 100 lbs soaking wet ;)

Just guessing here, but I bet that Eddy Merckx's hour record bike was 4/10 Record and not the 5/10 Record listed in the Columbus tubing catalog. It only needed to last one hour before "beer canning" a top tube ;)

Chuck Schmidt South Pasadena, California

Marc Boral wrote:
> Chuck and Richard seem to be of the opinion that "4/10 Record" refers to the
> guage/thickness. However I do not see the logic. Record tubes are 0.5 mm. for
> triangle tubes and all stays, and 0.8 for the head tube. How do you derive at the "4"
> in "4/10" pertaining to thickness? I was also told by Colnago that Record tubing was
> specked in only certain tubes on the frame, not throughout. So this is why I believe
> that "4/10" refers to how many Record tubes were used. Please submit your input,
> because I certainly do not want to share incorrect info.


> Marc Boral