Originally Posted by
karmat
26s are too small to convert most bikes that came with 27s or 700s. Many brakes are at their limit converting even to 650B from 700. Most can't even handle that. Aesthetics of 26s are poor IMHO as well, but of course that's a subjective argument.
The other problem with 26s is that outer wheel diameter is directly related to the ease with which you can maintain speed. The fewer rotations of the wheel, the lower the rolling resistance. Aero drag is going to be nearly equivalent. There's lots of information out there about wheel diameter and speed (here for example:
http://www.precisiontandems.com/artbillwheelsize.htm). Back to the point, though, 26s end up with a lower effective wheel diameter than 700s. 650B maintains that diameter while giving you a softer ride. And fits a lot more bikes.
Cheers,
Karl
I think that is the most concise explanation of why 650B and not 26" I've seen. I set up a 26" MTB for commuting/utility some years back, with the idea being getting a cushier ride. But even with fairly narrow, road oriented tires, I just felt it was too slow, and I'm not a speed demon or anything. So it seems that 650B's utility is in conversions of existing 700c/27" which can't fit wider tires, or perhaps even if you could, you don't want to raise the standover height. But for going out and buying a new dedicated bike, sized to fit and all, is there any benefit to buying a dedicated 650B rather than a 700c designed to fit wider tires (and fit the owner as well).
That all being said, I like the looks of 650B on smaller to mid-sized bikes, likewise a subjective issue.