A tire includes knob sets having leading edge bevels connected by a ramp. The leading edge bevels may be offset in their positions or angles. Each knob set includes a first knob attached to a second knob. The knobs in each set may differ in lengths or in the angles of the leading edge bevels. Each knob set shares a common base and includes a pair of elongate outermost surfaces divided by an optional axial channel. Each knob set includes a lateral edge, medial edge and a trailing edge. Transverse rows of two or more knob sets may vary in lateral spacing between knob sets to provide narrow and wide rows in an alternating pattern. Knob sets may also be included on sidewalls of the tire.