It'll be to do with the clearance. 650bx48c in 700c frame was a little close in some positions along the drop out. Nothing a bit of dimpling couldn't solve. Will dig out a photo later.
Don't think they make 650b frames in the larger sizes, if they do the distributor doesn't bring them in.
they make the 650b from 38-58cm - but yeah I'm sure you could tweak the stays a little. I'd rather get something off the peg that works. I'll keep thinking!
It'll be to do with the clearance. 650bx48c in 700c frame was a little close in some positions along the drop out. Nothing a bit of dimpling couldn't solve. Will dig out a photo later.
Don't think they make 650b frames in the larger sizes, if they do the distributor doesn't bring them in.