No chance.
1.85 is the biggest you'll get. 1.9 maybe.
I spoke to Brother and they said the chainstay gap is 54mm (2.1) at it's widest.
Factors including rim width and tyre manufacturers lies will swing a mm here and there.
Thanks - ok than regular 2.2 will be too fat fore sure.
I will build those 650b wheels any way so I will start some experiments. For the start I have some Soma Randonneur in 42 they will work for sure.
Ok nice ! How much clearance do you have ? Do you think a 2.2“ tire would fit ?