Yeah, but this one isn't (as far as I can tell).

Thanks, everyone, for your replies. I guess I'll just stick with the fattest 27" tires I can find, and assume it's all good enough. Obviously it's no more important than making sure nothing on the bike says "Made in Japan" on it.

I have a couple Veeder meters, which are very nice-- and they are marked. The one on my Norman (which has 27" wheels) is marked 26, and is very close to accurate (go figure).

I had a computer on this bike for a while, but it looked all wrong. On a 50's bike, a mileage meter like this seems more appropriate!