It will likely depend on the actual casing size on the tire - which tend to vary between manufacturers and even models of tires with the same manufacturer. The Bontrager 29-4 (which is a 29x2.3" tire) fits fine, but I haven't tried putting a Schwalbe Hans Dampf - which is a HUGE 2.35" tire - on one of these... It may not clear. So - it might require a bit of experimenting on your part to get your limits. Any friends you have that use a larger tire that you're interested in? Can you take one off of their bike and try it on yours before you lay out cash? If you can, post the findings you get! Some tires run "small" compared to their listed size, and others run large. Good luck!