2.25" WTB. Vigilante on the front and trail boss on the rear. Running Blunt 35 rims so they come up pretty big, probably on par with a 2.4 Ardent. Fork has about 5mm clearance at full compression! Not as fast in the dry as the 2.4/2.25 Ardent I originally spec'ed for it, but much more consistent grip around somewhere like Pitmedden.