JP4474232B2 - Pneumatic tire - Google Patents

Description

  The present invention relates to a pneumatic tire that achieves both high lateral rigidity and low vertical spring constant to improve running stability, and in particular, a bead outer wall having a concave curved surface recessed inward in the tire width direction is formed. The present invention relates to a pneumatic tire provided with a side rubber.

  In order to maintain the stability of the vehicle when the pneumatic tire gets over the unevenness of the road surface (that is, the ability of the vehicle body to move stably in the direction of travel when swinging), the pneumatic tire has a road surface. High performance is required as a buffering function against an impact input as disturbance from the unevenness of the surface. In order to enhance the performance as such a buffer function, as a characteristic of a pneumatic tire, there is a shock absorbability with respect to a longitudinal impact received from unevenness of a road surface and a convergence with respect to a lateral shake caused by the impact. It is important to achieve both.

  Also, in general, the vertical spring constant of a pneumatic tire is lowered (low vertical spring constant) in order to improve the shock absorption for the impact in the vertical direction, and the air is improved in order to improve the convergence with respect to the lateral deflection. What is necessary is just to make lateral rigidity of an entering tire high.

Therefore, conventionally, as a pneumatic tire with improved shock absorption for impact received from the road surface, a bead outer wall having a concave curved surface recessed inward in the tire width direction is provided on the outer side of the bead portion in the tire width direction, and further, a rim is provided. There has been proposed a pneumatic tire that secures a clearance in which the bead outer wall and the rim flange are separated from each other in the vicinity of the upper end of the flange and has improved shock absorption with respect to a longitudinal impact (see, for example, Patent Document 1).
Japanese Patent Laid-Open No. 11-217099

  The pneumatic tire based on the invention disclosed in Patent Document 1 is excellent in terms of enhancing the impact absorbability with respect to the impact in the longitudinal direction. However, as the speed of the vehicle increases in recent years, the impact with respect to the impact in the longitudinal direction is improved. There is a demand for a pneumatic tire that has both absorptivity and a convergence with respect to lateral runout.

  Accordingly, an object of the present invention is to achieve both high lateral rigidity and low vertical spring constant in a pneumatic tire including a bead outer wall having a concave curved surface recessed inward in the tire width direction on the outer side in the tire width direction of the bead portion. Another object of the present invention is to provide a pneumatic tire with improved shock absorption for impact from road surface irregularities and convergence for lateral runout and improved stability during running.

  In order to achieve the above object, the inventors of the present invention pay attention to the shape of the bead portion of the pneumatic tire (particularly the shape of the bead outer wall) and also to the thickness of the side rubber (side rubber gauge) on the bead outer wall. We paid attention and conducted research and analysis considering these factors in a complex way.

  First, the inventors modeled a pneumatic tire provided with a bead outer wall having a concave curved surface recessed inward in the tire width direction on the outer side of the bead portion in the tire width direction. The sensitivity analysis by the finite element method was performed using the shape of the rubber and the rubber gauge of the side rubber forming the bead outer wall as design variables, and the longitudinal spring characteristics and the lateral stiffness of the pneumatic tire were analyzed. As a result, the following was found.

  1) When the inner pressure is filled, the rubber gauge of the side rubber around the bead outer wall in contact with the rim flange is made thinner, and the radius of the concave curved surface of the bead outer wall is set larger than the radius of the curved surface of the rim flange facing the bead outer wall. (That is, a clearance is provided by separating at least a part between the bead outer wall and the rim flange), the contact pressure between the bead portion and the rim flange is reduced, and the vertical spring is maintained while maintaining the lateral rigidity of the pneumatic tire. It is possible to reduce the constant.

  2) Also, when filling the inner pressure, the side rubber of the bead outer wall near the upper end of the rim flange is thickened so that it protrudes in a protruding shape toward the bead outer wall, so that the vertical spring constant of the pneumatic tire is maintained. It is possible to increase the lateral rigidity while keeping it.

  The inventors have studied the bead shape and the rubber gauge of the side rubber, which are optimal for achieving both high lateral rigidity and low vertical spring constant, based on the above findings, and have come to the present invention. It was.

First, the first feature of the present invention is that a tread portion (tread portion 2), a pair of side portions (side portion 3) connected to the tread portion, and a pair of bead portions (bead portion 4) connected to the side portion. A pneumatic tire (pneumatic tire 1) including a carcass layer (carcass layer 7) disposed in an annular shape across the pair of bead portions via the tread portion and the pair of side portions. A side rubber (side rubber 9) is provided on the outer side in the tire width direction of the carcass layer, and at least a part of the outer side of the side rubber in the tire width direction is directed from the bead heel (bead heel 10) of the bead portion toward the outer side in the tire radial direction. extending to the bead outer wall Te (bead outer wall 4a) and is formed, contact in a state where the pneumatic tire is assembled the rim to define standard rim to be applied to the pneumatic tire The bead outer wall is in contact with the rim flange along the surface of the rim flange of the standard rim on the bead heel side, and is separated from the surface of the rim flange on the outer side in the tire radial direction from the contacting portion. are, the heel from the street and the tire axis parallel bead base line BL to the said bead position where rubber gauge is minimum of the side rubber in the bead outer wall at a position on the outer wall (minimum side rubber gauge position K ) And the rim flange height RH of the rim flange (rim flange 5a) of the specified standard rim (specified standard rim 5) is 0.4 <(KH / RH) <0.8, which is a position on the bead outer wall from the bead base line BL. The relationship between the maximum side rubber gauge height TH, which is the height up to the position where the rubber gauge of the side rubber becomes maximum (maximum side rubber gauge position T) on the bead outer wall, and the rim flange height RH is 0.9 <( TH / RH) <1.4, and the minimum side rubber gauge KW that is the minimum rubber gauge of the side rubber on the bead outer wall, and the maximum side rubber gauge TW that is the maximum rubber gauge of the side rubber on the bead outer wall; The relationship is in the range of 2.0 <(TW / KW) <7.0.

  Here, two actions obtained based on the first feature of the present invention will be described. As the effects obtained based on the first feature of the present invention, the action of reducing the longitudinal spring constant while minimizing the decrease in the lateral rigidity of the pneumatic tire and the increase of the longitudinal spring constant of the pneumatic tire are minimized. There is an effect of increasing the lateral rigidity while suppressing to a low level.

  More specifically, first, a minimum side rubber gauge height KH, which is a height from the bead base line BL to a position on the bead outer wall where the rubber gauge of the side rubber is minimum on the bead outer wall, and air It was specified that the relationship between the rim flange height RH of the rim flange of the standard specification rim that fits the entering tire is in the range of 0.4 <(KH / RH) <0.8.

  As a result, the longitudinal spring constant can be reduced while minimizing the decrease in lateral rigidity.

  Further, a maximum side rubber gauge height TH, which is a height from the bead base line BL to a position on the bead outer wall where the rubber gauge of the side rubber is maximum on the bead outer wall, and a rim flange height RH It was specified that the relationship was in the range of 0.9 <(TH / RH) <1.4.

  Thereby, it is possible to increase the lateral rigidity while minimizing an increase in the longitudinal spring constant.

  Further, the relationship between the minimum side rubber gauge KW that is the minimum rubber gauge of the side rubber on the bead outer wall and the maximum side rubber gauge TW that is the maximum rubber gauge of the side rubber on the bead outer wall is 2.0 <(TW / KW) <7. It was specified to be in the range of 0.

  As a result, the longitudinal spring constant can be reduced while minimizing the decrease in lateral rigidity.

  Therefore, by combining these actions, the pneumatic tire according to the first feature of the present invention can achieve both high lateral rigidity and low vertical spring constant.

The second feature of the present invention relates to the first feature of the present invention, and is the length AH of the portion of the bead outer wall spaced from the surface of the rim flange in the tire radial direction and the rim flange height RH. The relationship is in the range of 0.4 <(AH / RH) <1.0 .

  According to such a feature, at least a part of the bead outer wall contacts the rim flange, but the bead outer wall is within a predetermined range from the rim flange end E on the tire radial outer side of the rim flange toward the tire radial inner side. And the rim flange are separated from each other. In other words, between the bead outer wall and the rim flange, a range (tire diameter AH) exceeding 40% of the rim flange height RH from the rim flange end E toward the inner side in the tire radial direction. Clearance is provided over the width range of the direction.

  As a result, when the pneumatic tire gets over the road surface irregularities, the outer wall of the bead is deformed so as to swell outward in the width direction of the tire, so that the vertical spring constant of the pneumatic tire is further reduced and the shock absorption against the impact from the road surface. Is further improved.

  A third feature of the present invention relates to the first feature or the second feature of the present invention, wherein the carcass layer has a ply cord, and the ply cord has an angle of 65 degrees or more with respect to the tire equatorial plane CL. The gist is that the radial arrangement is S.

  The fourth feature of the present invention relates to the first to third features of the present invention, and is summarized in that the pneumatic tire is a tire for a two-wheeled vehicle.

  Providing pneumatic tires with improved stability during running by improving both high lateral rigidity and low vertical spring constant to improve shock absorption against impacts from road surface irregularities and to improve lateral convergence. can do.

  Next, an example of an embodiment of a pneumatic tire according to the present invention will be described with reference to the drawings. It should be noted that the drawings described in the following description are schematic and ratios of dimensions and the like are different from actual ones. Accordingly, specific dimensions and the like should be determined in consideration of the following description.

(Pneumatic tire structure)
FIG. 1 is a partial cross-sectional view in the tire width direction of a pneumatic tire 1 according to an embodiment of the present invention. The pneumatic tire 1 according to the present embodiment includes a tread portion 2, a pair of side portions 3 (on the opposite side not shown) continuous on both sides of the tread portion 2, and a pair of bead portions 4 (facing the opposite sides). And a carcass layer 7 disposed in an annular shape across the pair of bead portions 4 via the tread portion 2 and the pair of side portions 3.

  A bead core 6 is disposed inside the bead portion 4, and the carcass layer 7 is folded back so as to wind the bead core 6 and is terminated in the vicinity of the side portion 3.

  In addition, a belt layer 8 having two belt cords 8a and 8b is disposed on the outer side in the tire radial direction of the carcass layer 7 in order to protect the carcass layer 7.

  Further, on the outer side in the tire width direction of the carcass layer 7, a side rubber 9 that forms the outer side in the tire width direction of the bead part 4 and the side part 3 is provided. The side rubber 9 will be described in detail later with reference to FIG.

  FIG. 2 is an enlarged view of the vicinity of the bead portion 4 of the pneumatic tire 1 shown in FIG. The pneumatic tire 1 shown in the figure is assembled in a state in which the pneumatic tire 1 is completely fitted to the specified standard rim 5, the internal pressure is not filled, and the load is not loaded.

  Here, as a method of completely fitting the pneumatic tire 1 to the specified standard rim 5 in a state in which the internal pressure is not filled, for example, an air pressure higher than a specified internal pressure corresponding to the maximum static load load of the tire 1 assembled with the rim is temporarily provided. After filling and fitting the tire 1 to the specified standard rim 5 completely, the air pressure may be reduced to return to the state where the internal pressure has not been filled. At this time, it is preferable that the inner pressure of the rim-assembled tire 1 is zero, but a slight pressure (for example, 0.05 to 0.1 kgf / cm 2) that does not deform the tire 1 remains. Good.

  The prescribed standard rim 5 suitable for the pneumatic tire 1 is a standard rim having dimensions determined by a predetermined standard in which the pneumatic tire 1 is to be assembled. The standard rim applied here is an industry standard for each region where pneumatic tires are produced or used (for example, “JATMA Year Book” of the Japan Automobile Tire Association in Japan, “TRA Year Book” in the United States, Europe "ETRTO Standard Manual", etc.).

  As shown in FIG. 2, a side rubber 9 is disposed across the bead portion 4 and the side portion 3 on the outer side of the carcass layer 7 in the tire width direction.

  The side rubber 9 extends from the approximate center between the bead heel 10 and the bead toe of the bead part 4 to the outer end in the tire radial direction of the side part 3 (near the end part of the tread part 2), and the bead part 4 and the side part 3. And a side reinforcing rubber that forms the outer side in the tire width direction.

  A bead outer wall 4a having a concave curved surface 15 extending from the bead heel 10 of the bead portion 4 toward the outer side in the tire radial direction and recessed inward in the tire width direction is formed on the outer side of the side rubber 9 in the tire width direction.

  As shown in FIG. 2, at least a part of the bead outer wall 4 a comes into contact with the rim flange 5 a of the standard rim 5 when the pneumatic tire 1 is assembled to the standard rim 5.

  In the state in which the pneumatic tire 1 is assembled to the stipulated standard rim 5, the bead outer wall 4a is a rim from the rim flange end E, which is the end of the rim flange 5a in the tire radial direction, toward the tire radial inner side. In the range which becomes 40% or more of the flange height RH, it is separated from the rim flange 5a. That is, the bead outer wall 4a is in contact with the rim flange 5a on the inner side in the tire radial direction from the separated position A with respect to the separated position A which is a position on the bead outer wall 4a, and from the separated position A in the tire radial direction. On the outside, it is separated from the rim flange 5a. The separation width AH, which is the width in the tire radial direction from the rim flange end E to the separation position A, is a width exceeding 40% of the rim flange height RH (0.4 <(AH / RH)).

  If the separation width AH is 40% or less of the rim flange height RH, the effect of reducing the longitudinal spring constant cannot be sufficiently obtained, and the shock absorption is not improved so much.

  Further, the shape of the bead outer wall 4a may be a shape in which a concave curved surface 15 that is recessed inward in the tire width direction and a flat surface are combined. Alternatively, the concave curved surface 15 of the bead outer wall 4a may be a curved surface in which a plurality of curved surfaces having different radii having a center on the outer side in the tire width direction in the cross section in the tire width direction are combined.

  Further, as shown in FIG. 2, a minimum side rubber gauge height KH which is a height from the bead base line BL to a position K at which the rubber gauge of the side rubber 9 is minimum on the bead outer wall 4a, and a rim flange of the rim flange 5a. The relationship with the height RH is in the range of 0.4 <(KH / RH) <0.8.

  Further, the relationship between the maximum side rubber gauge height TH, which is the height from the bead base line BL to the position T at which the rubber gauge of the side rubber 9 is maximum on the bead outer wall 4a, and the rim flange height RH of the rim flange 5a is as follows. The range is 0.9 <(TH / RH) <1.4.

  The relationship between the maximum side rubber gauge TW at the position T at which the rubber gauge of the side rubber 9 is maximum on the bead outer wall 4a and the minimum side rubber gauge KW at the position K at which the rubber gauge of the side rubber 9 is minimum on the bead outer wall 4a is 2. The range is 0 <(TW / KW) <7.0.

  Here, the bead base line BL is a reference line passing through the bead heel 10 of the bead portion 4 and parallel to the tire axis.

  When the relationship (KH / RH) between the minimum side rubber gauge height KH and the rim flange height RH is 0.4 or less, the effect of reducing the longitudinal spring constant is reduced and the shock absorption is not improved so much. Therefore, it is not preferable. On the other hand, if (KH / RH) is 0.8 or more, the lateral stiffness starts to decrease, and the convergence with respect to the lateral deflection decreases.

  Further, when (TH / RH), which is the relationship between the maximum side rubber gauge height TH and the rim flange height RH, is 0.9 or less, the effect of reducing the longitudinal spring constant is reduced and the shock absorption is not improved so much. Therefore, it is not preferable. On the other hand, if (TH / RH) is 1.4 or more, the effect of improving the lateral rigidity is reduced, and the convergence with respect to the lateral shake is not improved so much.

  Further, when (TW / KW), which is the relationship between the maximum side rubber gauge TW and the minimum side rubber gauge KW of the side rubber 9, is 2.0 or less, the effect of reducing the longitudinal spring constant is reduced and the shock absorption is not improved so much. Therefore, it is not preferable. On the other hand, if (TW / KW) is 7.0 or more, the lateral rigidity starts to decrease, and the convergence with respect to the lateral deflection decreases.

  FIG. 3 is a partial plan development view of the carcass layer 7 disposed in the pneumatic tire 1 shown in FIG. As shown in the figure, the ply cord 7a of the carcass layer 7 has a radial arrangement arranged at an angle S of 65 degrees or more with respect to the tire equatorial plane CL.

(Comparison evaluation)
In order to confirm the effect of the present invention, the inventors based on the embodiment of the present invention described above, two types of pneumatic tires of comparative examples and four types of pneumatic tires of examples to which the present invention is applied. Each was manufactured and mounted on an actual vehicle (motorcycle), and a running test was performed. An evaluation test was performed to compare and evaluate the stability based on the conventional pneumatic tire.

  Note that the stability evaluation is an evaluation of the performance that allows the vehicle body to move stably in the direction of travel when swinging straight or turning. More specifically, disturbance input from road surface unevenness is a driving factor. This is a comprehensive evaluation of the degree of influence, that is, the absorptivity to the impact from the road surface and the convergence to the lateral shake.

  Data relating to comparative evaluation was collected under the following conditions (common to the conventional example, comparative example, and example).

・ Tire size: MCR120 / 70ZR17M / C
・ Carcass structure: 1 layer (rayon cord)
・ Belt structure: Two-layer cross belt (Kevlar belt x 2)
・ Tire pressure (internal pressure): 250kPa
・ Rim size: MT3.5 × 17
・ Evaluation vehicle ・ ・ ・ ・ Motorcycle (displacement: 1000cc)

  FIG. 4 is a partial cross-sectional view of a conventional pneumatic tire in the tire width direction. As shown in the figure, the conventional pneumatic tire is provided with a side rubber 23 that forms the outer side in the tire width direction from the bead part 4 to the side part 3 on the outer side in the tire width direction of the carcass layer 7. The outer wall of the bead portion 4 and the rim flange 5a are hardly separated (no clearance), which is different from the above-described embodiment of the present invention.

Table 1 summarizes the results of comparative evaluation of stability. The stability value is an index when the evaluation with the pneumatic tire of the conventional example is set to 100, and a larger value means a pneumatic tire with better stability.

(result)
The pneumatic tire of Comparative Example 1 has a minimum side rubber gauge height KH / rim flange height RH, a maximum side rubber gauge TW / minimum side rubber gauge KW, and a separation width AH / in comparison with the pneumatic tire according to the embodiment of the present invention. Each of the rim flange heights RH is a pneumatic tire that does not satisfy the numerical value range defined as preferable according to the present invention.

  The pneumatic tire of Comparative Example 2 has a relationship between the minimum side rubber gauge height KH and the rim flange height RH (KH / RH) as compared with the pneumatic tire of the embodiment according to the present invention. Each of the numerical values of (TW / KW), which is the relationship of the minimum side rubber gauge KW, is a pneumatic tire that does not satisfy the range of numerical values defined as preferable by the present invention.

  Both of the pneumatic tires of Comparative Example 1 and Comparative Example 2 have a lower stability evaluation than the conventional pneumatic tire.

  In addition, the pneumatic tires of Examples 1 to 4 have higher stability evaluation than the conventional pneumatic tires.

  Thus, from the results of the comparative evaluation of stability shown in Table 1, it is clear that the pneumatic tire having the characteristics of the present invention has high performance in running stability.

(Action / Effect)
According to the pneumatic tire 1 according to the present embodiment described above, first, from the bead base line BL to a position K on the bead outer wall 4a where the rubber gauge of the side rubber 9 is minimum on the bead outer wall 4a. The relationship between the minimum side rubber gauge height KH, which is the height of the rim flange, and the rim flange height RH of the rim flange 5a of the specified standard rim 5 suitable for the pneumatic tire 1 is 0.4 <(KH / RH) <0. A range of 8 was specified.

  As a result, the longitudinal spring constant can be reduced while minimizing the decrease in lateral rigidity.

  Further, the maximum side rubber gauge height TH, which is the height from the bead base line BL to the position T on the bead outer wall 4a where the rubber gauge of the side rubber 9 is maximum on the bead outer wall 4a, and the rim flange height It was specified that the relationship with the RH was in the range of 0.9 <(TH / RH) <1.4.

  Thereby, it is possible to increase the lateral rigidity while minimizing an increase in the longitudinal spring constant.

  Furthermore, the relationship between the minimum side rubber gauge KW which is the minimum rubber gauge of the side rubber 9 on the bead outer wall 4a and the maximum side rubber gauge TW which is the maximum rubber gauge of the side rubber 9 on the bead outer wall 4a is 2.0 <(TW / KW ) <7.0.

  As a result, the longitudinal spring constant can be reduced while minimizing the decrease in lateral rigidity.

  Therefore, by combining these actions, the pneumatic tire 1 according to the present embodiment can achieve both high lateral rigidity and low vertical spring constant.

  Therefore, according to the pneumatic tire 1 according to the present embodiment, both high lateral rigidity and low vertical spring constant are achieved, and the impact absorbability with respect to the impact from the road surface unevenness and the convergence with respect to the lateral deflection are improved. , Stability during running can be improved.

  Further, according to the pneumatic tire 1 according to the present embodiment, the rim flange height RH is further increased between the bead outer wall 4a and the rim flange 5a toward the inner side in the tire radial direction from the rim flange end E. Clearance is provided over a length range exceeding 40% (tire radial direction).

  As a result, when the pneumatic tire 1 gets over the road surface irregularities, the bead outer wall 4a is deformed so as to swell outward in the tire width direction, so that the longitudinal spring constant of the pneumatic tire 1 is further reduced and against the impact from the road surface. Impact absorption is further improved.

  Furthermore, in the pneumatic tire 1 according to the present embodiment in which the ply cord 7a of the carcass layer 7 is arranged at an angle S of 65 degrees or more with respect to the tire equatorial plane CL and is in a radial arrangement, the belt layer 8 The longitudinal spring constant of the tire due to the effect is originally high. In such a pneumatic tire 1, the present invention is more effective.

  Furthermore, if the pneumatic tire 1 according to the present embodiment is applied as a pneumatic tire for a two-wheeled vehicle that has been particularly remarkably increased in speed in recent years, the present invention is more effective.

1 is a partial cross-sectional view of a pneumatic tire 1 in a tire width direction. 2 is an enlarged view of the vicinity of a bead portion 4 of the pneumatic tire 1. FIG. FIG. 2 is a partial plan development view of a carcass layer 7 disposed in the pneumatic tire 1. It is a partial sectional view in the tire width direction of a pneumatic tire of a conventional example.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Pneumatic tire, 2 ... Tread part, 3 ... Side part, 4 ... Bead part, 4a ... Bead outer wall, 5 ... Standard specification rim, 5a ... Rim flange, 6 ... Bead core, 7 ... Carcass layer, 8 ... Belt Layer, 8a, 8b ... belt, 9 ... side rubber, 10 ... bead heel, A ... separated position, BL ... bead baseline, CL ... tire equator

Claims (5)

A tread part, a pair of side parts connected to the tread part, a pair of bead parts connected to the side part, and an annular arrangement across the pair of bead parts via the tread part and the pair of side parts. A pneumatic tire provided with a carcass layer provided,
A side rubber is provided on the outer side in the tire width direction of the carcass layer,
A bead outer wall extending from the bead heel of the bead portion toward the outer side in the tire radial direction is formed on at least a part of the outer side in the tire width direction of the side rubber ,
In a state where the pneumatic tire is assembled with a rim to a standard rim that is applied to the pneumatic tire,
The bead outer wall is
On the bead heel side, contacting the rim flange along the surface of the rim flange of the standard rim,
It is spaced apart from the surface of the rim flange on the outer side in the tire radial direction than the contacting part,
The minimum side rubber gauge height that is a height from a bead base line BL passing through the bead heel and parallel to the tire axis to a position on the bead outer wall where the rubber gauge of the side rubber is minimum on the bead outer wall. The relationship between the height KH and the rim flange height RH of the rim flange of the specified standard rim is in a range of 0.4 <(KH / RH) <0.8,
A maximum side rubber gauge height TH which is a height from the bead base line BL to a position on the bead outer wall where the rubber gauge of the side rubber is maximized on the bead outer wall; and the rim flange height The relationship with RH is in the range of 0.9 <(TH / RH) <1.4,
The relationship between the minimum side rubber gauge KW that is the minimum rubber gauge of the side rubber on the bead outer wall and the maximum side rubber gauge TW that is the maximum rubber gauge of the side rubber on the bead outer wall is 2.0 <(TW / KW) < A pneumatic tire characterized by being in the range of 7.0. The relationship between the length AH of the portion of the bead outer wall spaced from the surface of the rim flange in the tire radial direction and the rim flange height RH is in the range of 0.4 <(AH / RH) <1.0. the pneumatic tire according to claim 1, characterized in that. The relationship between the length AH of the portion of the bead outer wall spaced from the surface of the rim flange in the tire radial direction and the rim flange height RH is in a range of 0.4 <(AH / RH) ≦ 0.5. The pneumatic tire according to claim 1, wherein there is a pneumatic tire.   The carcass layer has a ply cord, and the ply cord has a radial arrangement disposed at an angle of 65 degrees or more with respect to the tire equatorial plane CL. A pneumatic tire according to any one of the above.   The pneumatic tire according to any one of claims 1 to 4, wherein the pneumatic tire is a motorcycle tire.

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