My current wheelset is the original 700c dyad rims. These have served well but will need to be replaced soon in any case due to brake track wear.

the widest tires possible on this frame with 700c is 32, which we have. (The limit is clearance at the chain stays).

As to why 650b? It would allow 42mm wide slicks. If you’ve only ridden 28’s, you might consider trying wider tires. Better ride and not slower. If I was buying a new bike, that’s what I’d spec.

on our bike, the easiest solution will prob be a new fork to take the 650b wheel and keep the same geometry. Our local frame shop can braze new canti studs on the stock fork pretty reasonably, so might do that.

just trying to figure out if there’s a new/better hub out there. I’ll prob just build the 650b’s on the original dt540s. They’ve been bombproof so far.