Originally Posted by
cyccommute
I have to disagree. Back in the day, Miyata, for example, didn't make a bike frame for the 27" market in the US and the 700C market in the rest of the world. Nor did Diacompe, for example, make brakes for the 27" market and the 700C market for the rest of the world. When 27" bikes were the "US bike" there was never a brake for one or the other. There were just brakes.
I do not believe this is accurate. In the 1970s, most trekking or touring bikes had 27", in Europe as well as USA, while most competition or 'racing' bikes had 700C. I just looked up some international catalogues from the era to confirm this...
https://labibleduvelocatalogueskogam...yata-1979.html
This one is in Dutch or something and the spec sheet at the back has 27" wheels and tires listed for some bikes.
The other problem with swapping wheel sizes without changing anything else is that, even if they can be made to fit, the build with smaller diameter wheels will have significantly stronger brakes for a given force at the lever than the one with larger wheels (for cantis - the opposite would be true of caliper brakes).