I bet you can get 650b 48mm in there.
Actually, I just realised you can just simply get a 650b wheelset, run 42mm tyres yet still have ample room for mudguard without any rub.
@edscoble started
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I bet you can get 650b 48mm in there.
Actually, I just realised you can just simply get a 650b wheelset, run 42mm tyres yet still have ample room for mudguard without any rub.