I'm looking for tires for a set of 700c Zipp 808 tubular rims.

Looking at PBK they have the Vittoria Corsa Evo CX 700 x 21mm in black, while some other colors are listed as 700C x 21mm. I thought the letter (width designator) no longer mattered for tubulars. These are the same sizes, yes (700 vs. 700C)?

Thanks

yep. I think so.

Yes, just be sure they aren't the Vittoria OPEN Corsa Evo CX which is the clincher version.

https://sheldonbrown.com/tire-sizing.html#french

Yes, I looked at this page. What is confusing is that PBK has the black tires listed as 700x21, without the "C":

https://www.probikekit.com/display.ph...oria%20Tubular

The "C" designation is a left over from many yeas ago when 700A and 700B wheels/tires were also available. These days 700C is the only survivor so the "C" is really redundant.

Off topic, but I'm using Vittoria Open Corsa's on my Pinarello; wow, what great ride quality those tires have.

Mr Riggs (my chem teacher) always said that numbers without units are just numbers.

I guess that they aren't actually tires at all, just numbers...

Bassplayinbiker....that is absolutely correct. In order to have a measurement one must have a number and a unit. I'm a HS chem teacher. That was actually a test question I gave them. lol!!!

These days the terms "700C", "650C", 26", etc. are really titles, not measurements. They define a wheel or tire type, not it's true dimensions.