Done a google search and it appears there are too many variables for a set in stone answer.
Heres how my profile stacks up.
Can anyone shed some light cos i ant got a scooby ?
Im 11 and a half stone.
Running 2.4 continental mountain kings (26)
And gunna be riding mixed terrain.
Not much road work.
Mostly muddy trails and the odd towpath !
Got em ramped up at 35 psi at the moment as suggested by my neighbour who mostly rides to work ?