| 摘要 |
A radial tyre for motorcycles which comprises at least one ply (6) of radially arranged organic fibre cords turned up around the bead cores (5) to form two turned up portions (6b) and a main portion (6a) therebetween; a tread disposed radially outside the carcass to define the tread portion (2), sidewalls (13) disposed axially outside the carcass to define the sidewall portions, a belt (7) disposed radially outside the carcass and inside the tread, a bead apex (9) disposed between the carcass main portion (6a) and each carcass turned up portion (6b) and extending radially outwardly and taperingly from the bead core (5), the radial height (Ht) of the radially outer edge of each carcass turned up portion (6a) being 0.3 to 0.5 times the radial height (Hs) of the tread edge, both measured from the bead base (15), the radial height (Ha) of the radially outer edge of each bead apex from the bead base (15) being 0.3 to 0.5 times said radial height (Hs) of the tread edge, the belt (7) composed of at least one spirally wound cord having an elastic modulus of not less than 600 kgf/sq.mm, and formed by winding spirally a ribbon of rubber in which at least one cord is embedded, and each sidewall (13) composed of an axially inner hard rubber layer (13a) having a JIS A hardness of 65 to 75 and an axially outer soft rubber layer (13b) disposed on the axially outside of the inner layer and having a JIS A hardness of not more than 60. <IMAGE> |
