Wire or folding bead tires? It would seem for MTB riding that a folding bead tire would be better because you run low tire pressures and the folding bead can take lower tire pressures. With a wire bead tire, the sidewalls would be stressed as you go over a bump and the sidewalls flex out. A folding bead tire's sidewalls are designed to flex. The folding bead would take the stress of the sidewalls flexing on every bump and undulation. Plus with a folding bead you would get a lower profile tire offering more traction.