So been offered a cracking deal on cube c62 carbon cross bike, will eventually sell a bike and go to two wheels sets for this.

the max tyre size it will take in a gravelly tyre is 700×37-38mm, anyone either fitted 650 wheels set to this bike or give a rough guide to what width 650 tyre will fit, ideally a 650 42 resolute would be great. i understand that its not an exact science due to stay shapes.

thanks

It depends

My older Arkose wasn’t designed around 650b. The fork would have been very limiting. The back took 700c 40mm and now takes 650b 50mm as the chain stays flared. The front would still have been 40mm on 650b. So i swapped the fork. The answer is it depends on the particular frame.

But the good news is that the 2 sets if wheels thing is going well

Surely depends on how kinked or not the chain and seat stays are.

Look at where the widest point of the tyre is for the 700x38s, look at the stays and fork inside edges at that point. Move 19mm down towards the axle and go out 2mm per side (38C vs 42C). If you have >5mm space there you’ll be OK for a similar shape tyre.
Resolutes measure 42mm across the shoulder of the tread, about 10-15mm below the max diameter point. The casing isn’t a true 42C.
Tricky if you can’t actually look at the bike but 650B Resolutes seem to fit most CX bikes whereas Byway 650x47s may not.

Add in to the mix that most tyres don’t actually measure whats written on them.

best is to try them!