650c vs. 26"?
 

What is the difference (if any) between the size of a 650c tire and a 26" tire?

624

Not much
 

650C rim diameter = 571 mm
26-inch MTB rim diameter = 559 mm

Note that a 32 mm 26-inch road tire (such as a Specialized FatBoy) will have almost exactly the overall diameter as a 23 mm 650C tire.

It depends on what 26" you're talking about: http://www.sheldonbrown.com/26/index.html#584

650c is a dead standard. Don't use that size.

There are still a lot of triathletes and short people who like it.

If you want to get angry at people pushing useless tire sizes, get angry at the folks who are trying to bring 650b back.

650b is the goldilocks of tire standards according to kogswell, rivendell, and some weirdo MTBers.

in either case you ought to make sure you keep an extra tube and maybe even a foldy tire handy. in the case of 650b this is super especially true cuz you ain't gonna find that **** in an emergency while walmart or your local hardware store ought to be able to help you with 26.