| 摘要 |
PURPOSE:To suppress heat emission from a tread part and enhance high speed durability by forming a belt layer from aromatic polymide fiber cords, and setting the initial modulus of elasticity of belt cord in the central region to a value greater than that in the shoulder region. CONSTITUTION:A belt layer 7 is composed of No.1 belt ply 11 consisting of aromatic group polyamide fiber cords, which are wound spirally in parallel with the tire equator C, and No.2 belt ply 12 wound in the opposite direction thereto. When this is divided into a central region M and a shoulder region S at a point P apart in the tire axial direction from the equator for a distance between 0.25 to 0.35 times as large as the tread width TW, the initial modulus of elasticity of each belt ply 11, 12 shall be greater in the central region M than in shoulder region S. This enhances the high speed durability. |
