The present invention concerns a tire (10) comprising a tread (11) provided with a base surface (14) and with a plurality of ribs (12), each rib (12) being provided with a front wall and a rear wall, and a shaped profile (15), wherein said shaped profile (15) has a section that defines at least one flat surface (17) of the shaped profile (15) which is parallel, or inclined at an angle α up to 20°, to the surface of the head (16) of the rib and which is joined to the front wall of the rib (12) by means of a connecting surface (18), at least one sharp angle (19) of the shaped profile (15) and at least one front wall (23) of the shaped profile (15), which is joint to said base surface (14) of the tread (11) by means of a connecting surface (21).