Tyre for motorcycles includes a carcass structure, a belt structure arranged in a radially outer position with respect to the carcass structure and a tread band arranged in a radially outer position with respect to the belt structure, wherein the belt structure is of the zero degree type and includes at least one reinforcing cord having an elongation at break smaller than about 3%; the cord includes a plurality of first metal wires twisted together so as to form a core of first metal wires and a plurality of second metal wires twisted together around said core; and the number and the diameter of the second metal wires are such that the second metal wires are not able to fully enclose the core.