Tyre (1) for a motor vehicle having a tread (2) comprising a central portion (L1) straddling an equatorial plane (7) and two shoulder portions, the central portion (L1) being separated from the shoulder portions (L2, L3) of the tread by two first circumferential grooves (3, 6), at least two second circumferential grooves (4, 5) being present in said central portion (L1). The second circumferential grooves (4, 5) define a central circumferential rib (10) comprising a plurality of sipes (20), arranged parallel to each other and spaced apart from each other. The second circumferential grooves (4, 5) have a mid-line extending in an undulating pattern along the circumferential extension of the tyre. The mid-lines with undulating pattern are substantially in phase with each other along the circumferential extension of the tyre (1).