A wheel assembly for use on vehicles in rugged conditions including, without limitation, off-road and trail conditions. A rim assembly having a rim flange is supported by a central hub member. The rim flange has a bead seat and allows a tire—including an under inflated tire—to flex without chaffing or cutting of the tire. A sacrificial abrasion ring is mounted to the outer surface of the rim flange. An optional removable accessory cap can mount to the wheel assembly to prevent mud, snow and/or other debris from collecting in the center of the wheel assembly.