What's "650b"? All I've come across are 26" ad 700c, the latter of which I understand to be "29"." Most of the so-called "commuter-bikes" I've encountered have been shown to come with "700X35" wheels, which, I believe, means they're twenty-nine inches by 1.5 inches, as opposed to the few I've seen in 26", which, too, are said to be 1.5 inches wide.