Self-supporting tyre for automotive wheels

A self-supporting tyre for automotive wheels comprising:

• a carcass structure comprising at least one carcass layer having opposite lateral edges associated with respective annular anchoring structures;
• a belt structure applied in a position radially external to the carcass structure;
• a tread band applied in a position radially external to the belt structure;
• a pair of sidewall structures each including a sidewall extended in a position axially external to the carcass structure and extended radially between one of the annular anchoring structures and an axially external portion of the tread band;
• a single first and a single second sidewall reinforcing insert, wherein the first and second inserts are each inside the respective sidewall structure of the tyre, at a position axially internal to the respective sidewall, and wherein the first sidewall reinforcing insert consists of an elastomeric compound (A) having a shear modulus value G′ of at least 1.25 MPa,
• the second sidewall reinforcing insert consists of an elastomeric compound (B) having a shear modulus value G′ of less than 1.25 MPa, wherein the moduli G′ is measured at 70° C., 10 Hz, 9% strain,
• a liner comprising a layer of air-impermeable elastomeric material located at the most radially internal position of the tyre and extending at least at the tread band, and
• an underliner comprising a layer of elastomeric material, located at a position radially external to the liner, radially internal to the carcass structure, axially internal to the sidewall reinforcing inserts, and
• wherein the elastomeric compound (A) comprises at least one reinforcing filler composition, the elastomeric compound (B) comprises at least one reinforcing filler composition, and the amount of the at least one reinforcing filler with respect to the total weight of elastomeric composition (A) is greater than the amount of the at least one reinforcing filler with respect to the total weight of elastomeric composition (B), and
• the underliner comprises the elastomeric compound (B) having the value of shear modulus G′ of less than 1.25 MPa, said modulus G′ being measured at 70° C. 10 Hz, 9% strain according to the Rubber Process Analyzer (RPA) method.