In reply to beardy mike:
> Tried fitting schwalbe sam smart 47's to my escapade and what I failed to take account of was side knob protrusion. They hit the chainstay but not the seat stays.
Many thanks. The above comment was spot on - 6mm clearance to chain stays, other narrow spots were 10mm to front mech clamp on seat tube and 12mm at crown of forks. Measured by prodding in screwdriver and tools with various diameter shafts to see what would fit and not fit in the clearance.
That's 6mm clearance with tyre marked 700x38c, 40-622 and 28x1.5.
Anybody know if sizing includes knobbles?
Assuming sizing does not include knobbles I think I can do same size tyre with knobbles.
42-622 (28 x 1.60, 700x40C) version of smart sam plus, only marginally bigger than 700x38c.
https://www.schwalbe.com/en/mtb-reader/smart-sam-plus
I guess if I just buy one and it doesn't fit on the back it will be OK on the front and I can look at something else for the back.
Thanks everyone!
Post edited at 17:14