Here's what Omnium has to say:
A good pair of mudguards will not only keep your back and feet dry, but also prolong the life of your drivetrain and other moving parts on your bike. V3 and WiFi compatible.
60mm version
The V3 & WiFi framesets have 70mm clearance between the chainstays, so a 29x2.25" tyre is the biggest we can recommend in combination with the 60mm mudguards!
Without mudguards it is possible to fit a 29x2.35" tyre (depending on tread pattern) but the clearances are tight, so expect some tyre buzz.
To play it safe, just stick to 29x2.15" tyres like the factory spec Schwalbe Big Ben Plus.
50mm version
The older frames like the Classic only have 50mm clearance between the chainstays, so a 700x43c tyre is the biggest that will fit under a set of 50mm mudguards.
Without the mudguards you will fit a 700x47c if you don't mind a bit of occasional tyre buzz.
