Patent ID: 11865867
Assignee: SUMITOMO RUBBER INDUSTRIES, LTD.
Field: Transport (Mechanical engineering)
Classification: CPC B  Y | IPC B

Claim 0:
1. A motorcycle tire comprising:
a tread portion with a ground contact surface,
a pair of sidewall portions,
a pair of bead portions each with a bead core therein,
a carcass extending between the pair of bead portions through the tread portion and the pair of sidewall portions, the carcass consisting of two carcass plies each comprising a plurality of carcass cords,, wherein
the tread portion comprises a tread rubber comprising a base rubber layer and a cap rubber layer disposed outward in a tire radial direction of the base rubber layer to form the ground contact surface of the tread portion,
the cap rubber layer comprises a crown cap portion disposed in a middle region in a tire axial direction of the tread portion and a pair of shoulder cap portions disposed in both sides in the tire axial direction of the crown cap portion,
the crown cap portion has a loss tangent tan δc in a range from 0.72 to 0.90 at 0 degrees C.,
the shoulder cap portions has a loss tangent tan δs in a range from 0.90 to 1.40 at 0 degrees C.,
the base rubber layer has a loss tangent tan δb at 0 degrees C., and
the loss tangents tan δc, tan δs and tan δb satisfy the following equation (1):

tan δc<tan δs≤tan δb  (1).