Originally Posted by
globecanvas
I don't quite understand how those things work. It looks like it is a metal shell that holds the BB30 bearings outside the frame rather than inside? Doesn't that add ~20mm to the BB width? How can the existing crank spindle be long enough? Obviously some lack of knowledge on my part.
The Specialized (and maybe the SRAM Red) BB30 bearings are less far apart than the Shimano setup. Wider is better - at least in our minds. Yes, the bearing holders (alloy) certainly would also introduce some flex, but I think it is less than the BB30 narrower set-up. Junior says he feels it. If he really does, or does not, that mental difference is reason enough to go one way over the other.