There was an article in VeloNews™ back in the early or mid 1980s about tires in general and Continentals tires in particular written by a Continental tire engineer.
That was the first article I read that explained about tire pressure and tire size and tire rolling resistance and their relationships (pressure in a vessel of different sizes and the pressure [tension] at the surface).
This was back when 700x18 tires were all the rage (didn't make any sense to me). The engineer wrote that for a clincher to have the same feel as the typical 22mm section width tubular (sewup), the clincher would have to have a section width of 28mm. That's when I started riding 25mm width tires, usually marked 700x28 back then.
Chuck Schmidt South Pasadena, Southern California
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