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
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| The nice thing about standards is that |
| there are so many of them to choose from. |
| --Andrew S. Tanenbaum |
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