Tires

A tire of the type having a radial carcass and a top belt for vehicles, which comprises a tread, sidewalls and beads, each flange portion of a sidewall having a filler section made from a hard rubber material surmounting the bead, said filler section being positioned between a portion of the carcass and folded-over edges of the carcass and comprising a rubbery material which is a rubbery mixture containing for 100 parts of natural or synthetic elastomer, from 50 to 90 parts of carbon black and from 20 to 50 parts of polyethylene or polypropylene having a high molecular weight of at least 500,000, said rubbery material having at the same time a dynamic modulus of at least about 200 kg/cm.sup.2 and a low hysteresis expressed by a low loss angle on the order of from about 7.degree. to 13.degree. and said sidewalls each having an exterior portion extending from a rim portion of the tire to the exterior lateral edges of the sides of the tread, each portion comprising a non-reinforced flexible rubbery material having a Shore hardness A of approximately 60 and a medium modulus of elasticity on the order of 15 kg/cm.sup.2 at 100% elongation.