They're basically 650b wheels with mountain-bike tires on them, right? Why? What's the use of a wheel size that's halfway between 26" and 29"? All this does is reduce tire companies' motivation to make a wide range of tires for the two existing mountain-bike tire sizes, and makes a whole bunch of equipment incompatible. 26" is good for short people like me, and people who like suspension, and 29" is good for tall people and people who dislike suspension. 27.5" serves no purpose that I can discern; it appears to draw a compromise between the two that doesn't need to exist.

Yeah, assuming 26" doesn't get phased-out entirely. Remember ISIS bottom-brackets? Brilliant idea, a better industry standard, totally killed when Shimano came out with outboard-bearing bottom-brackets.

I didn't even know "27 Five" was a new thing in the MTB market until I was discussing tire sizes with my bro'!
Shows how out of touch I am! <GRIN>

yes, looked it up and it's a 650B size wheel.

Typical marketing crap probably, "Duh, what size comes between 26" and 29" that we can try to sell to people as the new big thing............"

Then again 26" as a standard was a complete accident apparently..................

Col.