Pneumatic tire for motorcycle

A motorcycle pneumatic tire comprising:

• a pair of bead portions;
• a pair of side wall portions continuously extending on the respective bead portions;
• a tread portion toroidally extending between the side wall portions;
• and
• at least one carcass reinforcing the respective portions between the pair of the bead portions, wherein
• the tread portion is composed of a central rubber arranged in a tire width-direction central region sandwiching a tire equator and a side rubber arranged in both tire widthwise end portions having a lower modulus than the central rubber and having a structure in which the central rubber and the side rubber are sequentially laminated in both tire widthwise side portions, with the side rubber extending to a tire width-direction inner side further than a point at ¼ of a tread width (TW) on a tire width-direction outer side from a tire equator,
• a tire ground-contact surface has a tread pattern that includes plural inclined grooves, and
• when the tread width (TW) is equally divided in eight, among the thus equally-divided eight regions, a region (C) constituting a range of ¼ to ⅜ of the tread width (TW) on the tire width-direction outer side from the tire equator has the largest number of inclined grooves included per a single pitch of the tread pattern, and the depth of the inclined grooves is greater than the thickness of the side rubber in at least a part of the region (C);
• the central rubber and the side rubber are sequentially laminated in a tire radius-direction in both tire widthwise side portions;
• when the tread width (TW) is equally divided in eight and, based on the tire equator, a range from the tire equator to a point at ⅛ of the tread width (TW) on the tire width-direction outer side, a range of ⅛ to ¼ of the tread width (TW) on the tire width-direction outer side from the tire equator, a range of ¼ to ⅜ of the tread width (TW) on the tire width-direction outer side from the tire equator, and a range between ⅜ of the tread width (TW) on the tire width-direction outer side from the tire equator and a tread end are defined as regions A, B, C and D, respectively,
• the numbers nA, nB and nC of the inclined grooves included per the single pitch of the tread pattern in the respective regions A, B and C satisfy a relationship of nA≤nB<nC, in which an upper half part and a lower half part which correspond to parts of a same groove in a repeated groove pattern are counted as only 1 groove in the single pitch, and the number of inclined grooves included in each region is determined by measuring the tire width-direction distance between the tire width-direction ends of each inclined groove in each region and counting the number of inclined grooves that are included across 70% or more of the tire width direction of each region, and
• inclination angles θA, θB, θC and θD of the inclined grooves included in the respective regions A, B, C and D with respect to a tire circumferential direction satisfy a relationship of θA<θB<θC<θD;
• the number nA is 1 to 3, the number nB is 2 to 4, the number nC is 3 to 5, and the number nD is 1 to 3.