Tire for two-wheel vehicle

Abstract

To provide a tire for a two-wheel vehicle configured so that a step of a tread part can be prevented from wearing.SOLUTION: A tire for a two-wheel vehicle according to the present invention comprises a tread part 2. The tread part 2 includes a first tread end T1, a second tread end T2 and a grounding surface 10. The grounding surface 10 includes a first grounding surface 10A ranging from a tire equator C to the first tread end T1. When regions determined by dividing the first grounding surface 10A into five equal regions in an expanding width direction of the first grounding surface 10A are defined as a first region 11, a second region 12, a third region 13, a fourth region 14 and a fifth region 15 from the tire equator C side, a land ratio La2 of the second region 12 is larger than a land ratio La1 of the first region 11 and is larger than a land ratio La3 of the third region 13.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a tire for a motorcycle. [Background technology]

[0002] Patent Document 1 below proposes a pneumatic tire for motorcycles in which the land ratio of each part of the tread is specified. In this tire, the widthwise region from the tire equator to the tread end is divided into five equal parts, namely, first to fifth regions, and the magnitude relationship of the land ratio of each region is specifically specified. With the above characteristics, this tire is expected to improve transient characteristics such as response performance on wet road surfaces and grip performance at the start of cornering. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2016-141226 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the tire of Patent Document 1, when the tire is traveling straight (when the tire is traveling with a camber angle of 0°), the tire contact edge tends to be located near the second region. Step wear is likely to occur near the tire contact edge, and an improvement was required.

[0005] The present invention has been devised in view of the above circumstances, and has as its main object to provide a motorcycle tire capable of suppressing step wear of the tread portion. [Means for solving the problem]

[0006] The present invention is a motorcycle tire having a tread portion, the tread portion including a first tread edge, a second tread edge, and a contact surface between the first tread edge and the second tread edge, the contact surface including a first contact surface from the tire equator to the first tread edge, and when the first contact surface is divided into five equal regions in the developed width direction of the first contact surface, the regions being defined as a first region, a second region, a third region, a fourth region, and a fifth region from the tire equator side, a land ratio La2 of the second region is larger than the land ratio La1 of the first region and is also larger than the land ratio La3 of the third region. Effect of the Invention

[0007] The motorcycle tire of the present invention employs the above-mentioned configuration, and thus can suppress step wear in the tread portion. [Brief description of the drawings]

[0008] [Figure 1] 1 is a cross-sectional view showing one embodiment of a motorcycle tire of the present invention. [Diagram 2] FIG. 2 is a development of the contact surface of the tread portion of FIG. 1. [Diagram 3] FIG. 2 is a conceptual diagram showing a profile of a tread portion. [Figure 4] 3 is an enlarged view of the main inclined groove and the sub inclined groove of FIG. 2. [Diagram 5] FIG. 2 is an enlarged cross-sectional view of the tread portion of FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. The drawings are described to include the features of the present invention, but may include exaggerated expressions or expressions different from the dimensional ratios of the actual structure in order to facilitate understanding of the present invention. In addition, the same or common elements are given the same reference numerals throughout the embodiments, and duplicated descriptions are omitted. FIG. 1 is a tire meridian cross-sectional view including a tire rotation axis of a motorcycle tire 1 (hereinafter, sometimes simply referred to as a "tire") of this embodiment in a normal state. The tire 1 of this embodiment is a tire for the front wheel of a motorcycle suitable for on-road sports driving. In addition, the size of the tire 1 of this embodiment is, for example, 120 / 70ZR17. However, the tire of the present invention is not limited to such an embodiment.

[0010] In the case of a pneumatic tire for which various standards are established, the "normal state" refers to a state in which the tire is mounted on a normal rim, inflated to the normal internal pressure, and no load is applied. In the case of a tire for which various standards are not established, the normal state refers to a standard usage state according to the intended use of the tire, in which the tire is not mounted on a vehicle and no load is applied. In this specification, unless otherwise specified, the dimensions of each part of the tire are values ​​measured in the normal state. In addition, the dimensions of components that cannot be measured in the normal state (for example, the internal materials of tire 1) are values ​​measured with tire 1 in a state as close as possible to the normal state.

[0011] A "genuine rim" is a rim that is defined for each tire by the standard system that includes the standard on which the tire is based. For example, in the case of JATMA, it is called a "standard rim," in the case of TRA, it is called a "Design Rim," and in the case of ETRTO, it is called a "Measuring Rim."

[0012] "Normal internal pressure" is the air pressure set for each tire by each standard in the standard system on which the tire is based. In the case of JATMA, it is the "maximum air pressure." In the case of TRA, it is the maximum value listed in the table "TIRE LOAD LIMITS AT VARIOUS COLD INFLATION PRESSURES." In the case of ETRTO, it is the "INFLATION PRESSURE."

[0013] As shown in Fig. 1, a tire 1 of this embodiment includes a tread portion 2, a pair of sidewall portions 3, and a pair of bead portions 4. The sidewall portions 3 are continuous with both sides of the tread portion 2 in the tire axial direction. The bead portions 4 are continuous with the sidewall portions 3 on the inner side in the tire radial direction. A bead core 5 is embedded in the bead portions 4.

[0014] The tire 1 includes a carcass 6 extending between a pair of bead portions 4. The carcass 6 includes, for example, a carcass ply 6A including a plurality of carcass cords. The plurality of carcass cords are arranged at an angle of, for example, 65 to 90 degrees with respect to the tire circumferential direction (not shown). The carcass 6 in this embodiment is configured with one carcass ply 6A, but may be one in which a plurality of carcass plies are overlapped. The carcass ply 6A includes a main body portion 6a and a turn-up portion 6b. The main body portion 6a extends from the tread portion 2 through the sidewall portions 3 on both sides to the bead cores 5 of the bead portions 4 on both sides. The turn-up portion 6b is connected to the main body portion 6a and is turned up around the bead core 5 from the inside to the outside in the tire axial direction.

[0015] The tread portion 2 includes a tread reinforcing layer 9 arranged on the outer side of the carcass 6 in the tire radial direction, and a tread rubber 2G arranged on the outer side of the tread reinforcing layer 9 in the tire radial direction. The tread reinforcing layer 9 includes a belt layer 7 and a band layer 8 arranged on the outer side of the belt layer 7 in the tire radial direction.

[0016] The belt layer 7 is disposed adjacent to the carcass 6 on the outer side in the tire radial direction. The belt layer 7 is disposed so as to reinforce substantially the entire tread portion 2. The belt layer 7 includes, for example, two belt plies 7A and 7B. In these belt plies 7A and 7B, a plurality of belt cords are disposed at an angle of 10 to 40° with respect to the tire circumferential direction.

[0017] The band layer 8 is disposed, for example, in the center of the tread portion 2 in the tire axial direction, and is disposed so as to straddle at least the tire equator C. The band layer 8 includes, for example, at least one band cord wound spirally in the tire circumferential direction. Such a band layer 8 can suppress the growth of the outer diameter of the tread portion 2 during high-speed running.

[0018] The tread portion 2 includes a first tread edge T1, a second tread edge T2, and a ground contact surface 10 between the first tread edge T1 and the second tread edge T2. The ground contact surface 10 refers to the outer surface of the tread portion 2 that can come into contact with the ground when traveling straight or turning. The ground contact surface 10 is curved in an arc shape convex toward the outside in the tire radial direction in the tire meridian cross section so that a sufficient ground contact area can be obtained even when turning with a large camber angle. The first tread edge T1 and the second tread edge T2 correspond to the ends of the ground contact surface 10, and come into contact with the road surface at least when turning at the maximum camber angle. In the tire of this embodiment, the ground contact surface 10 is curved as described above, so that the tread width Wa constitutes the maximum tire width. The tread width Wa corresponds to the distance in the tire axial direction from the first tread edge T1 to the second tread edge T2.

[0019] Fig. 2 shows a development of the contact surface 10 of the tread portion 2. Fig. 2 corresponds to a diagram showing the contact surface 10 of the tread portion 2 developed on a plane. In this specification, the width of each portion in the tire axial direction in this state is referred to as the developed width. In addition, in this specification, the developed width from the first tread edge T1 to the second tread edge T2 is referred to as the tread developed width TW, and the developed width from the tire equator C to the first tread edge T1 or the second tread edge T2 is referred to as the tread developed half width TWh.

[0020] As shown in Fig. 2, the tread portion 2 has, for example, a directional pattern in which a rotational direction R is specified. The rotational direction R is indicated, for example, by letters or symbols on the sidewall portion 3 (shown in Fig. 1). However, the present invention is not limited to such an embodiment. Note that in some of the figures in this specification, the rotational direction R is indicated by an arrow.

[0021] The ground contact surface 10 includes a first ground contact surface 10A and a second ground contact surface 10B. The first ground contact surface 10A is an area from the tire equator C to the first tread edge T1. The second ground contact surface 10B is an area from the tire equator C to the second tread edge T2. The second ground contact surface 10B has substantially the same configuration as the first ground contact surface 10A.

[0022] In the present invention, the first ground contact surface 10A includes a first region 11, a second region 12, a third region 13, a fourth region 14, and a fifth region 15 aligned from the tire equator C toward the first tread edge T1. These regions correspond to five equal parts of the first ground contact surface 10A in the developed width direction. Therefore, the developed width W1 of each of these regions is 20% of the tread half developed width TWh.

[0023] The first region 11 is located closest to the tire equator C. The second region 12 is adjacent to the first tread edge T1 side of the first region 11. The third region 13 is adjacent to the second region 12 on the first tread edge T1 side. The fourth region 14 is adjacent to the third region 13 on the first tread edge T1 side. The fifth region 15 is located closest to the first tread edge T1 side, and is adjacent to the fourth region 14 on the first tread edge T1 side. In each figure in this specification, the boundary 16 between these regions is indicated by a two-dot chain line.

[0024] In the tire 1 of the present invention, the magnitude relationship of the land ratio of each region is specified. The "land ratio" is the ratio Sb / Sa of the actual contact area Sb of each region to the area Sa of a virtual contact surface formed by filling all the grooves, recesses, and sipes in each region.

[0025] In the present invention, the land ratio La2 of the second region 12 is larger than the land ratio La1 of the first region 11 and is also larger than the land ratio La3 of the third region 13. This makes it possible to suppress step wear of the tread portion 2. The reason for this is as follows.

[0026] FIG. 3 shows a conceptual diagram of the profile of the tread portion 2. In FIG. 3, profile 2A shown by a solid line corresponds to that of a new tire. Profile 2B shown by a two-dot chain line corresponds to that of a tire that has been worn to a certain extent. As shown in FIG. 3, since the profile of the tread portion 2 of a motorcycle tire is curved in an arc shape, the vicinity of the tire equator C is prone to wear. Furthermore, when a motorcycle is traveling straight (when traveling with a camber angle of 0°), within the actual ground contact area of ​​the tread portion 2, the edge of the ground contact area is located near the second region 12, and step wear is likely to occur near the second region 12.

[0027] In the present invention, the land ratio La2 of the second region 12 where step wear is likely to occur is made larger than the land ratios of the adjacent first region 11 and third region 13, so that the wear in these regions progresses uniformly. Therefore, the tire 1 of the present invention can effectively suppress step wear in the tread portion 2.

[0028] 2, in order to achieve the above-mentioned effects in the second ground surface 10B, the land ratio La2 of the second region 12 in the second ground surface 10B is larger than the land ratio La1 of the first region 11 and larger than the land ratio La3 of the third region 13. The features described below regarding the first ground surface 10A can also be applied to the second ground surface 10B. Therefore, the description of the second ground surface 10B is omitted.

[0029] A more detailed configuration of this embodiment will be described below. Each configuration described below shows a specific aspect of this embodiment. Therefore, it goes without saying that the present invention can achieve the above-mentioned effects even if it does not have the configuration described below. Furthermore, even if any one of the configurations described below is applied alone to the tire 1 of the present invention having the above-mentioned characteristics, an improvement in performance according to each configuration can be expected. Furthermore, when some of the configurations described below are applied in combination, a composite improvement in performance according to each configuration can be expected.

[0030] The land ratio La1 of the first region 11 is, for example, 81% to 91%, and preferably 84% to 88%. The land ratio La1 of the first region 11 is preferably 8 to 12 points smaller than the land ratio La2 of the second region 12. In a more preferable embodiment, the first region has the smallest land ratio among the five equal regions of the first ground contact surface 10A. This not only provides the above-mentioned effects, but also improves wet performance during straight driving.

[0031] The land ratio La2 of the second region 12 is, for example, 91% to 97%, and preferably 93% to 95%. In this embodiment, in a preferred embodiment, the second region has the largest land ratio among the five equally divided regions of the first ground contact surface 10A. This reliably suppresses step wear of the tread portion 2.

[0032] The land ratio La3 of the third region 13 is, for example, 83% to 93%, and preferably 86% to 90%. The land ratio La3 of the third region 13 is preferably 4 to 8 points smaller than the land ratio La2 of the second region 12. The land ratio La3 of the third region 13 is preferably larger than the land ratio La1 of the first region. Specifically, the land ratio La3 is preferably 2 to 6 points larger than the land ratio La1. As a result, when turning at a relatively small camber angle where the third region 13 is in contact with the ground, the transient characteristics of the response when the vehicle body is leaned becomes linear (hereinafter, such an effect may be simply referred to as "improved transient characteristics").

[0033] The land ratio La4 of the fourth region 14 is, for example, 89% to 93%. Moreover, the land ratio La4 of the fourth region 14 is preferably larger than the land ratio La3 of the third region 13. Specifically, the land ratio La4 is preferably 1 to 3 points larger than the land ratio La3. This further improves the transient characteristics during cornering.

[0034] The land ratio La5 of the fifth region 15 is, for example, 91% to 95%. The land ratio La5 of the fifth region 15 is preferably larger than the land ratio La4 of the fourth region 14. Specifically, the land ratio La5 is preferably 2 to 6 points larger than the land ratio La4. This allows excellent cornering performance to be exhibited when cornering at the maximum camber angle.

[0035] As a more preferable embodiment, the tire 1 of the present embodiment satisfies the following formula (1) for the land ratios La1 to La5 of the first to fifth regions, thereby further improving the transient characteristics during cornering. La2>La5>La4>La3>La1…(1)

[0036] As an example for achieving the above-mentioned land ratio, a plurality of main inclined grooves 20 and a plurality of sub inclined grooves 25 having the following characteristics are provided in the first contact surface 10A of the tread portion 2 of the present embodiment in the tire circumferential direction. However, the tire 1 of the present invention is not limited to the specific tread pattern shown in FIG.

[0037] The length P1 of one pitch of the main inclined grooves 20 in the tire circumferential direction (the distance between two adjacent main inclined grooves 20) is, for example, 70% to 90% of the tread developed width TW. The sub inclined grooves 25 are also arranged in a similar manner. In a preferred embodiment, in a developed view of the tread portion 2, an area obtained by virtually extending one main inclined groove 20 in parallel to the first tread end T1 side overlaps with another main inclined groove 20 adjacent to one side in the tire circumferential direction (upper side in FIG. 2). In this embodiment, the main inclined grooves 20 are arranged in the above-mentioned positional relationship over the entire tire circumference. This can suppress uneven wear of the tread portion 2 and improve the transient characteristics during cornering.

[0038] Moreover, it is preferable that a region obtained by virtually extending one main oblique groove 20 in parallel toward the first tread edge T1 side overlaps with two sub oblique grooves 25. This improves wet performance.

[0039] FIG. 4 shows an enlarged view of the main inclined groove 20 and the sub inclined groove 25. As shown in FIG. 4, the main inclined groove 20 is inclined toward the first tread edge T1 side, for example, toward the opposite side of the rotation direction R. The average angle θ1 of the main inclined groove 20 with respect to the tire circumferential direction is, for example, 5 to 10°. The average angle θ1 corresponds to a value obtained by dividing the groove center line of the main inclined groove 20 into a plurality of minute regions and dividing the sum of the angles of each minute region with respect to the tire circumferential direction by the number of the minute regions. The same applies to the following description in this specification. Such a main inclined groove 20 can exhibit excellent drainage performance by utilizing the rotation of the tire during wet driving.

[0040] The main inclined grooves 20 are arranged, for example, across the first region 11, the second region 12, the third region 13, and the fourth region 14. Moreover, the main inclined grooves 20 are not arranged in the fifth region 15. In a preferred embodiment, the main inclined grooves 20 do not cross the tire equator C. As a result, the length L1 of one main inclined groove 20 in the tire circumferential direction is 130% to 200% of one pitch length P1 (shown in FIG. 2) of the main inclined groove 20.

[0041] The main oblique groove 20 includes, for example, a narrow groove portion 21, an inner portion 22, and an outer portion 23. The narrow groove portion 21 is disposed in the longitudinal center of the main oblique groove 20 and extends with a relatively small constant groove width W2. The inner portion 22 is continuous with the narrow groove portion 21 on the tire equator C side and has a groove width larger than that of the narrow groove portion 21. The outer portion 23 is continuous with the narrow groove portion 21 on the first tread edge T1 side and has a groove width larger than that of the narrow groove portion 21.

[0042] The groove width W2 of the narrow groove portion 21 is, for example, 3.0 mm or less, preferably 0.5 to 2.5 mm, and more preferably 1.0 to 2.0 mm. Moreover, most of the narrow groove portion 21 is disposed in the second region 12. Specifically, 80% or more of the opening area of ​​the narrow groove portion 21 is disposed in the second region 12. This makes it possible to increase the land ratio La2 of the second region 12, and thus to realize the above-mentioned land ratio relationship.

[0043] For example, 80% or more of the opening area of ​​the inner portion 22 is disposed in the first region 11. In the present embodiment, the entire inner portion 22 is disposed in the first region 11. The average groove width of the inner portion 22 is larger than the groove width W2 of the narrow groove portion 21. The average groove width corresponds to the value obtained by dividing the opening area of ​​the inner portion 22 by the length of the groove center line of the inner portion 22. The same applies to the following description in this specification. The majority of the inner portion 22 is disposed in the first region 11. Specifically, 90% or more of the opening area of ​​the inner portion 22 is disposed in the first region 11. This ensures wet performance during straight driving.

[0044] The outer portion 23 is disposed across the third region 13 and the fourth region 14, and is not disposed in the second region 12 or the fifth region 15. The average groove width of the outer portion 23 is larger than the groove width W2 of the narrow groove portion 21. In addition, 50% or more, preferably 60% or more, of the opening area of ​​this outer portion 23 is disposed in the third region 13, and the remainder is disposed in the fourth region 14. This improves the transient characteristics during cornering.

[0045] The sub inclined grooves 25 are disposed closer to the first tread edge T1 than the main inclined grooves 20. The sub inclined grooves 25 are inclined in the same direction as the main inclined grooves 20 with respect to the tire circumferential direction. The average angle θ2 of the sub inclined grooves 25 with respect to the tire circumferential direction is, for example, 30 to 50°. In a desirable embodiment, the average angle θ2 of the sub inclined grooves 25 is larger than the average angle θ1 of the main inclined grooves 20. This improves stability during cornering at a relatively large camber angle where the fourth region 14 or the fifth region 15 comes into contact with the ground.

[0046] The sub-inclined groove 25 is disposed across the fourth region 14 and the fifth region 15. The main inclined groove 20 is not disposed in the third region 13. The sub-inclined groove 25 does not open to the first tread edge T1. In a preferred embodiment, the region of the sub-inclined groove 25 extended parallel to the tire axial direction overlaps with both the narrow groove portion 21 and the outer portion 23 of the main inclined groove 20. The axial distance between the end 25a of the sub-inclined groove 25 on the tire equator C side and the end 20a of the main inclined groove 20 on the first tread edge T1 side is preferably 10% or less, more preferably 5% or less of the developed width W1 (shown in FIG. 2) of each region. The circumferential length L2 of the sub-inclined groove 25 is 10% to 25% of the circumferential length L1 of the main inclined groove 20. This further improves the transient characteristics during cornering.

[0047] 5 shows an enlarged cross-sectional view of the tread portion 2 in FIG. 1. As shown in FIG. 5, the tread rubber 2G of the tread portion 2 includes a crown rubber 31 and two shoulder rubbers 32 made of a rubber material different from that of the crown rubber 31. The crown rubber 31 includes the tire equator C, and the shoulder rubber 32 includes the first tread edge T1 or the second tread edge T2. As a result, the ground contact surface 10 of the tread portion 2 is configured to include the crown rubber 31 and the shoulder rubber 32. A known rubber material can be applied to the crown rubber 31 and the shoulder rubber 32 so that the desired performance can be achieved.

[0048] Between the tire equator C and the first tread edge T1, the crown rubber 31 and the shoulder rubber 32 are connected via a boundary surface 33. A boundary 33a between the crown rubber 31 and the shoulder rubber 32 is located in the first contact surface 10A. This boundary 33a is located closer to the first tread edge T1 than the second region 12, and is preferably located in the third region 13 or the fourth region 14. This makes it possible to more effectively suppress step wear of the tread portion 2.

[0049] The loss tangent tan δ of the crown rubber 31 at 0° C. is preferably larger than the loss tangent tan δ of the shoulder rubber 32 at 0° C. This makes it easier for the crown rubber 31 to rise to an appropriate temperature when starting to drive. Also, the loss tangent tan δ of the shoulder rubber 32 at 70° C. is preferably larger than the loss tangent tan δ of the crown rubber 31 at 70° C. This makes it easier for the temperature of the shoulder rubber 32 to rise, and high grip is exhibited when cornering.

[0050] In this specification, the loss tangent tan δ is a value measured in accordance with the provisions of JIS-K6394 under the following conditions using a viscoelasticity spectrometer manufactured by Iwamoto Seisakusho Co., Ltd. Initial distortion: 10% Amplitude: ±1% Frequency: 10Hz Deformation mode: tension

[0051] In the cross section of the tread portion 2, a boundary surface 33 between the crown rubber 31 and the shoulder rubber 32 extends linearly. An angle θ3 of the boundary surface 33 with respect to the tire normal is, for example, 30 to 50°.

[0052] For example, the axial end 8a of the band layer 8 is located axially inside of the boundary surface 33. In this embodiment, the boundary 33a is located in the third region 13, and the tire normal 8b passing through the end 8a of the band layer 8 is located in the second region 12. By arranging the band layer 8 in this manner, step wear of the tread portion 2 is further suppressed.

[0053] Although a motorcycle tire according to one embodiment of the present invention has been described in detail above, the present invention is not limited to the specific embodiment described above and can be modified and carried out in various aspects.

[0054] [Note] The present invention includes the following aspects.

[0055] [Invention 1] A tire for a motorcycle having a tread portion, The tread portion includes a first tread edge, a second tread edge, and a contact surface between the first tread edge and the second tread edge, the contact surface includes a first contact surface from a tire equator to the first tread edge, When the first ground contact surface is divided into five equal regions in the development width direction of the first ground contact surface, the regions are defined as a first region, a second region, a third region, a fourth region, and a fifth region from the tire equator side, A land ratio La2 of the second region is larger than a land ratio La1 of the first region and is also larger than a land ratio La3 of the third region. Tires for motorcycles. [Invention 2] The motorcycle tire according to the first aspect of the present invention, wherein a land ratio La3 of the third region is larger than a land ratio La1 of the first region. [Invention 3] The land ratio La4 of the fourth region is larger than the land ratio La3 of the third region, The land ratio La5 of the fifth region is greater than the land ratio La4 of the fourth region. A tire for a two-wheeled vehicle according to the present invention 2. [Invention 4] The motorcycle tire according to the third aspect of the present invention, wherein the second region has the largest land ratio among the five equally divided regions. [Invention 5] The land ratio La1 of the first region is 81% to 91%, The land ratio La2 of the second region is 91% to 97%, 5. The motorcycle tire according to any one of claims 1 to 4, wherein the land ratio La3 of the third region is 83% to 93%. [Invention 6] The ground contact surface includes a crown rubber and a shoulder rubber made of a rubber material different from the crown rubber, A boundary between the crown rubber and the shoulder rubber is located on the first ground contact surface, The tire for a motorcycle according to any one of claims 1 to 5, wherein the boundary is located closer to the first tread end than the second region. [Invention 7] 7. The motorcycle tire according to claim 6, wherein the boundary is located in the third region or the fourth region. [Invention 8] 8. The motorcycle tire according to claim 6 or 7, wherein a loss tangent tan δ of the crown rubber at 0° C. is greater than a loss tangent tan δ of the shoulder rubber at 0° C. [The present invention 9] The motorcycle tire according to any one of claims 6 to 8, wherein a loss tangent tan δ of the shoulder rubber at 70°C is greater than a loss tangent tan δ of the crown rubber at 70°C. [The present invention 10] the contact surface includes a second contact surface from the tire equator to the second tread edge, When the second ground contact surface is divided into five equal regions in the development width direction of the second ground contact surface, the regions are defined as a first region, a second region, a third region, a fourth region, and a fifth region from the tire equator side, The motorcycle tire according to any one of claims 1 to 9, wherein, in the second contact surface, a land ratio La2 of the second region is larger than a land ratio La1 of the first region and is also larger than a land ratio La3 of the third region. [Explanation of symbols]

[0056] 2 Tread section 10 Ground plane 10A 1st ground plane 11 First area 12 Second area 13 Third area 14 4th area 15 5th area La1 Land ratio of the first region La2 Land ratio of the second region La3 Land ratio of the third region T1 First tread edge T2 Second tread edge

Claims

1. A tire for a motorcycle having a tread portion, The tread portion includes a first tread edge, a second tread edge, and a contact surface between the first tread edge and the second tread edge, the contact surface includes a first contact surface from a tire equator to the first tread edge, When the first ground contact surface is divided into five equal regions in a development width direction of the first ground contact surface, the regions are defined as a first region, a second region, a third region, a fourth region, and a fifth region from the tire equator side, a land ratio La2 of the second region is larger than a land ratio La1 of the first region and is also larger than a land ratio La3 of the third region; Tires for motorcycles.

2. The motorcycle tire according to claim 1 , wherein a land ratio La3 of the third region is greater than a land ratio La1 of the first region.

3. The land ratio La4 of the fourth region is greater than the land ratio La3 of the third region, A land ratio La5 of the fifth region is greater than a land ratio La4 of the fourth region. A tire for a motorcycle according to claim 2.

4. The motorcycle tire according to claim 3 , wherein the second region has the largest land ratio among the five equally divided regions.

5. The land ratio La1 of the first region is 81% to 91%, The land ratio La2 of the second region is 91% to 97%; The motorcycle tire according to any one of claims 1 to 4, wherein a land ratio La3 of the third region is 83% to 93%.

6. The ground contact surface includes a crown rubber and a shoulder rubber made of a rubber material different from the crown rubber, A boundary between the crown rubber and the shoulder rubber is located on the first ground contact surface, The tire for a motorcycle according to claim 1 , wherein the boundary is located closer to the first tread edge than the second region.

7. The motorcycle tire according to claim 6 , wherein the boundary is located in the third region or the fourth region.

8. The motorcycle tire according to claim 6, wherein a loss tangent tan δ at 0° C. of the crown rubber is greater than a loss tangent tan δ at 0° C. of the shoulder rubber.

9. The motorcycle tire according to claim 6, wherein a loss tangent tan δ at 70° C. of the shoulder rubber is greater than a loss tangent tan δ at 70° C. of the crown rubber.

10. the contact surface includes a second contact surface from the tire equator to the second tread edge, When the second ground contact surface is divided into five equal regions in the development width direction of the second ground contact surface, the regions are defined as a first region, a second region, a third region, a fourth region, and a fifth region from the tire equator side, 5. The motorcycle tire according to claim 1, wherein, in the second contact surface, a land ratio La2 of the second region is larger than a land ratio La1 of the first region and is also larger than a land ratio La3 of the third region.

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