quote:and it probably saves the manufacturers money throughout the industry to have one standard size...yeah, but if there's one thing the bike tire industry DOESN'T have, it's standardization. Check out Sheldon Brown's site about tire sizes, it's mind-bogling. Anyhow, ranting aside, another big reason is that the 700C clincher is (supposed to be) the same diameter as the standard sewup/tubular. Big benefit for both the bike builders and especially for racers since you could easily swap one for the other and leave the brakes as they were...say, if you wanted to train on clinchers but race on tubs. And the first lightweight clinchers were French products (Module E and Rigida) so they were certainly going to make them metric, metric IS French.