Just been given a set of new tyres from a mate and he suggested sticking the fatter tyre on the front for cornering grip if the weather is wet this weekend.

He has given me 1 x Trailracker 1.9 and 1 x Bontrager Mud X 2.0

Is he right?

Yes theory is big front tyre floats over the mud narrow rear tyre cuts through mud for grip.

Big front, smaller rear will slacken the angles of the bike a touch (though not a massive difference in tyre volumes) and vice versa

depends which is grippier for your sort of mud. You want the back to wash out first. My trailrakers didn’t like our local mud whereas mud x’s do (and seem much better over roots and rock), so if it was me on my local trails i would start with the mud x on the front. But you might find if your mud is ‘wetter’ then you get more sideways grip from the trailraker.

yes fatter on the front,I ran that combination of tyre at the Selkirk Merida last year and it was exellent. 😀

The trailraker can be a bit draggy once on the road though,and i only use it as a race tyre.