My answer was too quick. Sheldon is right about the English dimensions rather than the metric conversion I supplied.
Joe Bender-Zanoni Great Notch, NJ "Hey, it might be 28.6 after paint"
> Richard Cielec asked:
>
> >What is the OD of R531 and the clamp diameter for the correct front
> >der. for English bikes (Carlton, Raleigh, Witcomb, Holdsworth,
> >etc...) ? Is this spec'd in English or Metric?
>
> Standard traditional steel frames use 1 1/8" seat tube and down tube,
> 1" top tube.
>
> Old French bikes used metric tubing, 28 mm seat and down, 25 mm top tube.
>
> Back in the days of lugs, there was little variation in tube diameter
> because builders wanted to be able to use standard lugs. This also
> limited frame geometry, because the angles of tube joints in the lugs
> could only be varied to a limited extent.
>
> The move to TIG welding made a much wider range of affordable frame
> designs possible...this technology first made its mark in BMX, later
> in MTB.
>
> Sheldon "History" Brown
> Newtonville, Massachusetts
> +---------------------------------------------+
> | The nice thing about standards is that |
> | there are so many of them to choose from. |
> | --Andrew S. Tanenbaum |
> +---------------------------------------------+
> --
> Harris Cyclery, West Newton, Massachusetts
> Phone 617-244-9772 FAX 617-244-1041
> http://harriscyclery.com
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