My ~1950 Carlton Flyer (24" frame) has the weight of an SL frame (1950 grams, before it was repaired), and it's made of Reynolds Tubing :
http://www.ece.ubc.ca/
I think of classic tubing in terms of 3 different kinds of 'tubesets' :
7/4/7 tubing, has a toptube with walls of .7mm, .4mm, .7mm 8/5/8 tubing, has a toptube with walls of .8mm, .5mm, .8mm 9/6/9 tubing, has a toptube with walls of .9mm, .6mm, .9mm
The seat tube is the same, but one end is not butted (e.g. 7/4/4, or 8/5/5, or 9/6/6) because the aluminum seatpost forms the butt at the top of the seat lug.
The downtube is normally 1 gauge heavier in all 3 dimensions, compared to the top tube. It doesn't matter what reynolds (or Ishiwata or Columbus or Dedaccai or even Nova Cycles) calls it, what matters in terms of flexion is the gauge(s) of the tubing.
I found a website with Reynolds advertisements, a history of Reynolds tube sets, and interview information with Reynolds officials :
http://fivenineclimber.com/
If you scroll down halfway, you'll find out that the tubesets weight:
7/4/7 weighs 1900 531 'Professional' or 'SL' or just 'Light' 8/5/8 weighs 2050 531 'Competition' or just regular 531 9/6/9 weighs 2200 531 'Super Tourist' or 'Special Tourist'
Tange and Reynolds at different times made a 6/3/6 top tube. Tange 6/3/6 top tubes were used on SEKAI 5000 superlight framesets, and Reynolds 6/3/6 top tubes was part of the 'Reynolds 753 TRACK' tube set.
- Don Gillies
San Diego, CA, USA
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