JP7230549B2 - motorcycle tire - Google Patents

Description

The present invention relates to tires for motorcycles.

Patent Literature 1 listed below describes a motorcycle tire having a tread provided with grooves. The groove includes a crown main groove extending continuously in the tire circumferential direction within the crown region, an inclined groove having an inner end located within the crown region and an outer end located within the shoulder region, and a slant groove located within the shoulder region. shoulder sub-grooves disposed between the oblique grooves.

JP 2016-210247 A

Motorcycle tires as described above have excellent wet performance. However, in recent years, as motorcycles have been driven at higher speeds, it has been required to improve transient characteristics during cornering while maintaining wet performance. The "transitional characteristic" refers to the response when the motorcycle is tilted during cornering. Further, "to enhance the transient characteristics" means that the response is smooth and stable turning traveling is possible.

SUMMARY OF THE INVENTION The present invention has been devised in view of the problems described above, and a main object of the present invention is to provide a motorcycle tire capable of improving transient characteristics while maintaining wet performance.

The present invention is a motorcycle tire having a tread portion, wherein the tread portion includes a plurality of first inclined grooves inclined with respect to the tire circumferential direction and a plurality of grooves inclined in the same direction as the first inclined grooves. The first inclined groove extends from the crown region to the shoulder region, the second inclined groove is provided between the adjacent first inclined grooves, and the second inclined groove is provided between the adjacent first inclined grooves. The inclined groove extends axially outward from the inner end located in the shoulder region, and the angle of the second inclined groove with respect to the tire circumferential direction is formed at a position in the tire circumferential direction passing through the inner end of the second inclined groove. The absolute value |θ2−θ1| of the difference between θ2 and the angle θ1 of the first inclined groove with respect to the tire circumferential direction is 10 degrees or less.

In the motorcycle tire according to the present invention, it is desirable that the absolute value |θ2−θ1| is 5 degrees or less.

In the motorcycle tire according to the present invention, it is preferable that the angle θ2 of the second inclined groove is 50 degrees or less.

In the motorcycle tire according to the present invention, it is preferable that the angle θ2 of the second inclined groove is 40 degrees or less.

In the motorcycle tire according to the present invention, it is preferable that the axial length of the second inclined grooves is 40% to 50% of the axial length of the first inclined grooves.

In the motorcycle tire according to the present invention, the absolute value of the difference |θ2− It is desirable that θ3| is 40 degrees or more.

In the motorcycle tire according to the present invention, it is preferable that the width of the second inclined groove gradually increases toward the outside in the axial direction of the tire.

In the motorcycle tire according to the present invention, it is preferable that the groove width at the inner end of the second inclined groove is 70% or less of the groove width at the outer end of the second inclined groove in the tire axial direction. .

In the motorcycle tire according to the present invention, it is preferable that the axial distance from the inner end of the second inclined groove to the tire equator is 25% to 35% of the tread development width.

In the motorcycle tire according to the present invention, the first inclined groove includes a first portion extending linearly and a second portion extending arcuately outside the first portion in the tire axial direction. It is desirable that one portion extends so as to intersect the tire circumferential direction position passing through the inner end of the second inclined groove.

In the motorcycle tire according to the present invention, in a cross section obtained by cutting the first inclined groove along the longitudinal direction, the first inclined groove has a groove bottom, and an axial direction between the groove bottom and the first inclined groove. and a first inner groove wall connecting the groove bottom and the axially inner end of the first inclined groove, wherein the tire normal line of the first outer groove wall The inclination angle with respect to the direction is preferably the same as the inclination angle with respect to the tire normal direction of the first inner groove wall.

In the motorcycle tire according to the present invention, in a cross section obtained by cutting the second inclined groove along the longitudinal direction, the second inclined groove has a groove bottom, and an axial direction between the groove bottom and the second inclined groove. and a second inner groove wall connecting the groove bottom and the inner end of the second inclined groove, wherein the second inner groove wall is inclined with respect to the normal direction of the tire. The angle is preferably greater than the angle of inclination of the second outer groove wall with respect to the normal direction of the tire.

The motorcycle tire of the present invention has a plurality of first slanted grooves and a plurality of second slanted grooves, and therefore has excellent wet performance.

Further, in the motorcycle tire, at a position in the tire circumferential direction passing through the inner end of the second inclined groove, the angle θ2 of the second inclined groove with respect to the tire circumferential direction and the angle of the first inclined groove with respect to the tire circumferential direction Since the absolute value |θ2−θ1| of the difference from θ1 is set to 10 degrees or less, excellent transient characteristics can be obtained from straight running to cornering.

1 is a tire meridian sectional view of a motorcycle tire according to an embodiment of the present invention; FIG. FIG. 2 is an exploded view of the tread portion of FIG. 1; FIG. 3 is an enlarged view of FIG. 2; (a) is a cross-sectional view taken along line BB of FIG. 2, (b) is a cross-sectional view along line CC of FIG. 2, and (c) is a cross-sectional view along line DD of FIG.

An embodiment of the present invention will be described below with reference to the drawings.
FIG. 1 is a tire meridian cross-sectional view of a motorcycle tire (hereinafter sometimes simply referred to as "tire") 1 showing an embodiment of the present invention in a normal state. The "normal state" is a no-load state in which the tire 1 is mounted on a normal rim (not shown) and filled with a normal internal pressure. In this specification, unless otherwise specified, the dimensions of each portion of the tire 1 are values measured under normal conditions.

The above-mentioned "regular rim" is a rim defined for each tire in the standard system including the standard on which the tire 1 is based. ", or "Measuring Rim" for ETRTO.

The "regular internal pressure" is the air pressure determined for each tire by each standard in the standard system including the standard on which the tire 1 is based. LIMITS AT VARIOUS COLD INFLATION PRESSURES", or "INFLATION PRESSURE" for ETRTO.

In the tire 1 of this embodiment, the tread contact surface 2a between the tread ends 2t of the tread portion 2 is curved and extends outward in the tire radial direction in a convex arc shape. Such a tire 1 can obtain a sufficient ground contact area even during cornering with a large camber angle. The tire axial distance between the tread ends 2t when the tread portion 2 is developed on a plane is the tread developed width TWe.

Inside the tire 1 of this embodiment, tire constituent members such as a carcass 6 and a belt layer 7 are arranged. Known aspects are appropriately adopted for these tire constituent members.

FIG. 2 is a developed view of the tread portion 2 of the tire 1 of this embodiment. As shown in FIG. 2, the tread portion 2 of this embodiment includes a crown region Cr including the tire equator C, a pair of middle regions Mi, Mi arranged on both sides of the crown region Cr, and an outer side of the middle region Mi. and a pair of shoulder regions Sh, Sh arranged at

The crown region Cr has, for example, a tire axial width Wc that is 20% to 25% of the tread developed width TWe with the tire equator C as the center in the tire axial direction. The crown region Cr is a region that touches the ground during straight running. The shoulder region Sh has a tire axial width Ws that is 20% of the tread developed width TWe from the tread end 2t. The shoulder region Sh is a region where the tread edge 2t touches the ground during turning with a large camber angle.

The tread portion 2 includes, for example, a plurality of first inclined grooves 10 that are inclined with respect to the tire circumferential direction, and a plurality of first inclined grooves 10 that are provided between adjacent first inclined grooves 10 and inclined in the same direction as the first inclined grooves 10. and a second inclined groove 11 of . Thereby, the tire 1 of this embodiment has excellent wet performance.

The first inclined groove 10 and the second inclined groove 11 are arranged on both sides of the tire equator C in this embodiment. The tread pattern of the tread portion 2 of the present embodiment is line-symmetrical with respect to the tire equator C, but is not limited to such a form.

The first inclined groove 10 extends from the crown region Cr to the shoulder region Sh. Such a first inclined groove 10 effectively discharges the water film between the tread contact surface 2a of the tread portion 2 and the road surface. In addition, since the first inclined groove 10 as described above reduces the rigidity step between the crown region Cr and the shoulder region Sh, the transitional characteristics from straight running to turning running are maintained at a high level.

The second inclined groove 11 extends axially outward from an inner end 11i located in the shoulder region Sh. Thus, the second inclined grooves 11 of the present embodiment are formed only in the shoulder region Sh, and improve the wet performance during cornering with a large camber angle.

FIG. 3 is an enlarged view of the tread portion 2 of FIG. As shown in FIG. 3, the shoulder region Sh includes an inner portion Si having an axial width Wd of 10% of the tread developed width TWe from the inner end in the tire axial direction, and an axially outer portion of the inner portion Si. and the outer part So. The outer portion So is the region where the greatest lateral force acts.

In this embodiment, at a position P in the tire circumferential direction passing through the inner end 11i of the second inclined groove 11, the angle θ2 of the second inclined groove 11 with respect to the tire circumferential direction and the angle θ1 of the first inclined groove 10 with respect to the tire circumferential direction The absolute value of the difference |θ2−θ1| is 10 degrees or less. As a result, at the tire circumferential position P passing through the inner end 11i, the difference between the axial component of the edge 10s of the first inclined groove 10 and the edge 11s of the second inclined groove 11 is kept small. Therefore, the direction of the lateral force generated by both inclined grooves 10 and 11 is aligned, so the transient characteristics are enhanced from straight running to cornering. The absolute value of the difference |θ2−θ1| is preferably 5 degrees or less in order to exhibit the above-described effect more effectively. At the inner end 11i, the edge 11s of the second inclined groove 11 intersects with the groove center line 11c continuously formed at the middle position of the groove width W2 in the direction perpendicular to the longitudinal direction of the second inclined groove 11. Defined by position. Also, the angle θ2 is the angle of the groove center line 11 c of the second inclined groove 11 . Further, the angle θ1 is the angle of the groove center line 10c of the first inclined groove 10. As shown in FIG. The groove centerline 10c of the first slanted groove 10 is defined similarly to the groove centerline 11c of the second slanted groove 11 .

In this embodiment, the angle θ1α of the second inclined groove 11 with respect to the tire circumferential direction and the angle of the first inclined groove 10 with respect to the tire circumferential direction are The absolute value |θ2α−θ1α| of the difference from θ2α is 10 degrees or less. As a result, high transient characteristics can be obtained over the length L2 of the second inclined grooves 11 in the axial direction of the tire. More preferably, the absolute value of the difference |θ2α−θ1α| is 5 degrees or less.

In this embodiment, the first inclined groove 10 includes a linearly extending first portion 14 and an arcuately extending second portion 15 outside the first portion 14 in the axial direction of the tire. The second portion 15 smoothly changes the direction of the lateral force acting on the first inclined groove 10 over the axial direction of the tire, thereby enhancing transient characteristics. In this specification, the second portion 15 refers to a portion in which both edges 10k, 10k extending in the longitudinal direction of the first inclined groove 10 have curvature at the tire circumferential direction position. The first portion 14 refers to a portion closer to the tire equator C than the second portion 15 in the tire circumferential direction. In FIG. 3, one second portion 15 is colored for convenience.

An axially inner end 15i of the second portion 15 is provided, for example, in the inner portion Si. This further enhances the transient characteristics during large cornering where the shoulder region Sh touches the ground.

The angle θ1α of the second portion 15 with respect to the tire circumferential direction gradually increases outward in the tire axial direction. As a result, the length Le in the tire circumferential direction of the land portion between the second portions 15 adjacent in the tire circumferential direction gradually increases outward in the tire axial direction. Therefore, the rigidity in the tire axial direction of the land portion between the second portions 15 is enhanced, and traction suitable for turning is exhibited. Although not particularly limited, in the outer portion So, the angle θ1α of the first inclined groove 10 is 60 degrees or more.

The first portion 14 extends to intersect a tire circumferential position P passing through the inner end 11 i of the second inclined groove 11 . That is, in the present embodiment, the first portion 14 with low drainage resistance extends from the crown region Cr to the shoulder region Sh, so wet performance is enhanced.

Although not particularly limited, the axial length L1 (shown in FIG. 2) of the first inclined groove 10 is preferably, for example, 35% to 45% of the tread development width TWe. Such first inclined grooves 10 improve wet performance while maintaining the rigidity of the land portion.

The second inclined groove 11 extends in an arc shape in this embodiment. The angle θ2α of the second inclined groove 11 with respect to the tire circumferential direction, for example, gradually increases outward in the tire axial direction. As a result, the rigidity in the tire axial direction of the land portion between the second inclined groove 11 and the first inclined groove 10 is maintained high, thereby improving turning performance. In addition, the second inclined groove 11 is not limited to such an arc-shaped form.

The tire axial distance La from the inner end 11i of the second inclined groove 11 to the tire equator C is preferably 25% to 35% of the tread developed width TWe. When the tire axial distance La is less than 25% of the tread developed width TWe, the rigidity of the land portion of the middle region Mi is reduced, and there is a risk that the transient characteristics will be deteriorated. If the tire axial distance La exceeds 35% of the tread development width TWe, wet performance may deteriorate.

In order to effectively exhibit the above effects, the axial length L2 of the second inclined groove 11 is, for example, 40% to 50% of the axial length L1 of the first inclined groove 10. desirable.

The angle θ2 at the inner end 11i of the second inclined groove 11 is desirably 50 degrees or less. Since the inner end 11i is arranged at the position in the tire axial direction as described above, if the angle θ2 exceeds 50 degrees, the second inclined groove 11 may not be able to obtain a preferable edge effect. Moreover, if the angle θ2 exceeds 50 degrees, the drainage resistance of the second inclined groove 11 may increase. In order to exhibit the above effect more effectively, it is more desirable that the angle θ2 of the second inclined groove 11 is 40 degrees or less.

The absolute value |θ2−θ3| of the difference between the angle θ2 at the inner end 11i of the second inclined groove 11 and the angle θ3 with respect to the tire circumferential direction at the axially outer end 11e of the second inclined groove 11 is 40 degrees. It is desirable to be above. As a result, lateral force can be generated in multiple directions by the second inclined grooves 11, so excellent turning performance can be obtained. The outer end 11e, like the inner end 11i, is specified at a position where the groove center line 11c of the second inclined groove 11 and the edge 11s intersect on the tread end 2t side.

As shown in FIG. 2, in this embodiment, the second inclined groove 11 has a groove width W2 that gradually increases toward the outside in the tire axial direction. Such a second inclined groove 11 maintains a small change in the rigidity of the land portion between the second portions 15 in the circumferential direction of the tire, thereby enhancing transient characteristics.

The groove width W2a at the inner end 11i of the second inclined groove 11 is preferably 70% or less of the groove width W2b at the outer end 11e of the second inclined groove 11. If the groove width W2a at the inner end 11i exceeds 70% of the groove width W2b at the outer end 11e, the change in rigidity in the tire circumferential direction of the land portion between the second portions 15 becomes large, possibly degrading the transient characteristics. There is In this specification, the groove width W2a at the inner end 11i is the groove width at a position spaced axially outward from the inner end 11i by the groove width W2g at the intermediate position in the tire axial direction of the second inclined groove 11. is. Further, the groove width W2b at the outer end 11e is the groove width at a position spaced apart from the outer end 11e by the groove width W2g of the second inclined groove 11 axially inward. Although not particularly limited, the groove width W2a at the inner end 11i of the second inclined groove 11 is preferably 20% or more of the groove width W2b at the outer end 11e of the second inclined groove 11.

The groove width W2a at the inner end 11i of the second inclined groove 11 is preferably 50% or less of the groove width W1p (shown in FIG. 3) of the first inclined groove 10 passing through the position P in the tire circumferential direction. Thereby, it is possible to suppress a decrease in the rigidity of the land portion between the first inclined groove 10 and the second inclined groove 11 in the vicinity of the inner end 11i. In order to maintain wet performance, the groove width W2a of the second inclined grooves 11 is preferably 20% or more of the groove width W1p of the first inclined grooves 10. As shown in FIG.

FIG. 1 is a cross-sectional view taken along line AA of FIG. As shown in FIG. 1, in a longitudinal section of the first inclined groove 10, the first inclined groove 10 includes a groove bottom 10j, a first outer groove wall 10a and a first inner groove wall 10b. I'm in. The groove bottom 10j extends substantially parallel to the tread contact surface 2a of the tread portion 2. As shown in FIG. The first outer groove wall 10a joins the groove bottom 10j and the axially outer end 10e of the first inclined groove 10 and is inclined. The first inner groove wall 10b is inclined by joining the groove bottom 10j and the inner end 10i of the first inclined groove 10 in the tire axial direction.

The inclination angle α1 of the first outer groove wall 10a with respect to the tire normal n direction is, for example, the same as the inclination angle α2 of the first inner groove wall 10b with respect to the tire normal n direction. Such a first inclined groove 10 reduces the difference in rigidity between the land portions near the outer end 10e and the inner end 10i. As a result, higher transient characteristics can be obtained from straight running to cornering. Although not particularly limited, the inclination angle α1 and the inclination angle α2 are desirably 10 to 30 degrees, for example.

In a longitudinal section of the second inclined groove 11, the second inclined groove 11 includes a groove bottom 11j, a second outer groove wall 11a and a second inner groove wall 11b. The groove bottom 11j extends substantially parallel to the tread contact surface 2a of the tread portion 2. As shown in FIG. The second outer groove wall 11a joins the groove bottom 11j and the outer end 11e of the second inclined groove 11 and is inclined. The second inner groove wall 11b joins the groove bottom 11j and the inner end 11i of the second inclined groove 11 and is inclined.

The inclination angle α4 of the second inner groove wall 11b with respect to the tire normal n direction is, for example, greater than the inclination angle α3 of the second outer groove wall 11a with respect to the tire normal n direction. The second inner groove wall 11b continues to the inner end 11i having a relatively small groove width, and the load acting on the tire 1 tends to be concentrated. Therefore, by increasing the inclination angle α4 of the second inner groove wall 11b, cracks and chipping at the inner end 11i of the second inclined groove 11 can be suppressed. In addition, such second inner groove wall 11b reduces the change in rigidity of the land portion near the inner end 11i. Therefore, the turning performance of the tire 1 is maintained high. Although not particularly limited, the inclination angle α4 is preferably 25 to 45 degrees greater than the inclination angle α3. Also, the inclination angle α4 is desirably 45 to 65 degrees. The inclination angle α3 is desirably 10 to 30 degrees.

Although not particularly limited, the groove width W1p (shown in FIG. 2) of the first inclined groove 10 is preferably about 5 to 12 mm. A groove depth D1 of the first inclined groove 10 is preferably about 4 to 9 mm. A pitch P1 (shown in FIG. 2) in the tire circumferential direction in the crown region Cr of the first inclined grooves 10 is preferably about 3 to 9 times the groove width W1p of the first inclined grooves 10 . Further, the groove width W2b (shown in FIG. 2) at the outer end 11e of the second inclined groove 11 is desirably about 3 to 9 mm. A groove depth D2 of the second inclined groove 11 is preferably about 2 to 7 mm.

As shown in FIG. 2, the tread portion 2 of the present embodiment is provided with a pair of circumferential grooves 12 continuously extending in the tire circumferential direction. The circumferential groove 12 of this embodiment is arranged in the crown region Cr. The circumferential grooves 12 are arranged on both sides of the tire equator C, for example. Note that, for example, a plurality of circumferential grooves 12 exceeding two may be formed.

The circumferential groove 12 extends linearly in this embodiment. As a result, water can be drained efficiently during straight running at high speeds, thereby enhancing wet performance. Note that the circumferential grooves 12 are not limited to such a form, and may extend in a zigzag or wavy form, for example.

The circumferential groove 12 does not continue with the first inclined groove 10 . Thereby, the rigidity of the land portion of the crown region Cr is maintained high.

A groove width W3 of the circumferential groove 12 is preferably about 5 to 12 mm. Moreover, the groove depth D3 (shown in FIG. 1) of the circumferential groove 12 is preferably about 4 to 9 mm.

4(a) is a cross-sectional view along the BB line in FIG. 2, FIG. 4(b) is a cross-sectional view along the CC line in FIG. 2, and FIG. 4(c) is a cross-sectional view along the DD line in FIG. is. 4A to 4C are cross-sectional views cut in a direction orthogonal to the groove centerline. As shown in FIGS. 4A to 4C, in this embodiment, the angle α5 of the groove wall of the first inclined groove 10 with respect to the tire normal n direction is It is larger than the angle α7 with respect to the n-direction. Since the first inclined grooves 10 are also arranged in the middle region Mi and the shoulder region Sh, a larger lateral force acts than the circumferential grooves 12 arranged in the crown region Cr. Therefore, by making the angle α5 relatively large, a decrease in rigidity in the vicinity of the first inclined groove 10 is suppressed, and running performance including transient characteristics is enhanced.

The angle α6 of the groove wall of the second inclined groove 11 with respect to the tire normal n direction is smaller than the angle α7 of the groove wall of the circumferential groove 12 with respect to the tire normal n direction. Such a second inclined groove 11 exhibits an edge effect, and can enhance stability performance during cornering with a large camber angle.

In order to effectively exhibit the above action, the angle α5 is preferably 13 to 23 degrees, for example. The angle α6 is preferably 3 to 10 degrees, for example. The angle α7 is desirably 10 to 20 degrees, for example.

Although the embodiments of the present invention have been described in detail above, it is needless to say that the present invention is not limited to the illustrated embodiments, and can be implemented in various modifications.

Motorcycle tires having the basic structure shown in FIG. 1 were prototyped based on the specifications shown in Table 1, and wet performance and transient characteristics of each sample tire were tested. The main common specifications and test methods for each sample tire are as follows.
Groove width/TWe of the first inclined groove, groove depth: 3.3%, 6.5 mm
Groove width/TWe of circumferential groove, groove depth: 2.7%, 6.5 mm
Groove width W2b/TWe of the second inclined groove, groove depth: 2.2%, 5.0 mm
Inclination angle α3 of the second outer groove wall: 20 degrees

<Transient characteristics/wet performance>
Each test tire was mounted on all wheels of a large motorcycle under the following conditions, and was run on a dry asphalt test course and a wet asphalt test course with a water depth of 5 mm. Smoothness and stability when leaning the vehicle on a dry asphalt road surface, and stability when the vehicle goes straight and turns on a wet asphalt road surface were confirmed. The results are evaluated on a 20-point scale by the sensory perception of the test riders. A larger value is better.
Tires (front wheels, rear wheels): 120/70R17, 190/60R17
Rim (front wheel, rear wheel): MT3.50, MT5.50
Tire internal pressure (front wheel, rear wheel): 240kPa, 160kPa
Test vehicle: Motorcycle with a displacement of 1000 cc "Gradual increase" in Table 1 means that the groove width gradually increases toward the tread end side. The "first portion" refers to a mode in which a position in the tire circumferential direction passing through the inner end of the second inclined groove intersects with the first portion. The "second portion" refers to a mode in which a position in the tire circumferential direction passing through the inner end of the second inclined groove intersects with the second portion.
Table 1 shows test results and the like.

As a result of the test, it was confirmed that the tire of the example is superior in transient characteristics while maintaining wet performance as compared with the tire of the comparative example.

1 motorcycle tire 2 tread portion 10 first inclined groove 11 second inclined groove 11i inner end Cr crown region Sh shoulder region

Claims (11)

A motorcycle tire having a tread portion,
The tread portion is provided with a plurality of first inclined grooves inclined with respect to the tire circumferential direction and a plurality of second inclined grooves inclined in the same direction as the first inclined grooves,
The first inclined groove extends from the crown region to the shoulder region,
The second inclined grooves are provided between adjacent first inclined grooves,
The second inclined groove extends axially outward from an inner end located in the shoulder region,
At a position in the tire circumferential direction passing through the inner end of the second inclined groove, the absolute value |θ2 of the difference between the angle θ2 of the second inclined groove with respect to the tire circumferential direction and the angle θ1 of the first inclined groove with respect to the tire circumferential direction. -θ1| is 10 degrees or less,
In a cross section of the second inclined groove cut along the longitudinal direction, the second inclined groove has a groove bottom, and a second outer groove wall connecting the groove bottom and the outer end of the second inclined groove in the tire axial direction. and a second inner groove wall joining the groove bottom and the inner end of the second inclined groove,
The inclination angle of the second inner groove wall with respect to the tire normal direction is greater than the inclination angle of the second outer groove wall with respect to the tire normal direction,
Motorcycle tires. The motorcycle tire according to claim 1, wherein said absolute value |θ2-θ1| is 5 degrees or less. The motorcycle tire according to claim 1 or 2, wherein said angle θ2 of said second inclined groove is 50 degrees or less. The motorcycle tire according to claim 1 or 2, wherein the angle θ2 of the second inclined groove is 40 degrees or less. The motorcycle tire according to any one of claims 1 to 4, wherein the axial length of the second inclined grooves is 40% to 50% of the axial length of the first inclined grooves. The absolute value |θ2−θ3| of the difference between the angle θ2 of the second inclined groove and the angle θ3 at the axially outer end of the second inclined groove with respect to the tire circumferential direction is 40 degrees or more. Item 6. The motorcycle tire according to any one of Items 1 to 5. The motorcycle tire according to any one of claims 1 to 5, wherein the width of the second inclined groove gradually increases toward the outer side in the tire axial direction. The motorcycle tire according to claim 7, wherein the groove width at the inner end of the second inclined groove is 70% or less of the groove width at the axially outer end of the second inclined groove. The motorcycle tire according to any one of claims 1 to 8, wherein the tire axial distance from the inner end of the second inclined groove to the tire equator is 25% to 35% of the tread development width. The first inclined groove includes a first portion extending linearly and a second portion extending arcuately outside the first portion in the axial direction of the tire,
The motorcycle tire according to any one of claims 1 to 9, wherein the first portion extends so as to intersect the tire circumferential direction position passing through the inner end of the second inclined groove. In a cross section of the first inclined groove taken along the longitudinal direction, the first inclined groove has a groove bottom, and a first outer groove wall connecting the groove bottom and the outer end of the first inclined groove in the axial direction of the tire. and a first inner groove wall connecting the groove bottom and the axially inner end of the first inclined groove,
The motorcycle tire according to any one of claims 1 to 10, wherein the inclination angle of the first outer groove wall with respect to the tire normal direction is the same as the inclination angle of the first inner groove wall with respect to the tire normal direction. .

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