JP4695156B2 - Pneumatic tire for motorcycle and manufacturing method thereof - Google Patents

Description

  The present invention relates to a pneumatic tire for a motorcycle and a manufacturing method thereof.

A tread of a conventional pneumatic tire is formed by winding one piece of a wide band-shaped tread rubber substantially equal to the tread width of a finished tire around the outer periphery of a belt layer or the like attached to a crown portion of a carcass ply. Band-wound tread (see, for example, Patent Document 1), and spiral tread in which band-shaped rubber is spirally wound around the outer periphery of the belt layer or the like (over substantially the entire tread width of the finished tire) (Patent Document 2 and Patent Document 3) Reference) and width direction division tread (see Patent Document 4 and Patent Document 5).
JP-A-9-239865 Japanese Patent Laid-Open No. 10-323917 JP-A-11-320706 JP-A-4-146121 Japanese Patent Laid-Open No. 4-146122

  However, the pneumatic tire for motorcycles has a much larger tread drop rate than the tire for passenger cars, and the outer diameter is significantly different between the tread center and the tread end in the tire axial direction. The difference is big. For this reason, in the above-described band-wound tread, the tread end portion is greatly squeezed during vulcanization molding due to the circumferential length difference between the tread center portion and the tread end portion, and the tread rubber tends to bend or overlap at the tread end portion. As a result, there has been a problem that the tread thickness is not uniform in the tire circumferential direction.

  When the tread thickness is not uniform, there is a problem that the uniformity of the product tire is deteriorated to cause vibration and jumping, and minute vibration called chattering during actual vehicle driving is deteriorated.

  On the other hand, in the spiral tread, although the non-uniformity of the thickness due to the wrinkle at the end of the tread is improved, there is a problem that the manufacturing time becomes long due to the spiral winding.

  In particular, in the case of a spiral tread that uses two or more types of rubbers that are different at the center portion of the tread and both sides thereof, such as a width-direction divided tread, it is necessary to change the rubber type, which further increases the manufacturing time. . In order to make it unnecessary to switch the rubber type, it is conceivable to use a raw ribbon tread rubber extrusion device directly connected to a molding machine, but this device must be prepared by the number of rubber types, which increases costs. There is a problem.

  In consideration of the above facts, the present invention aims to improve uniformity, wear resistance and durability while minimizing the manufacturing cost in a pneumatic tire for a motorcycle having a large tread drop rate. To do.

The invention according to claim 1 is provided on an outer peripheral surface of a band assembly including at least a pair of bead cores, a carcass ply straddling one bead core and the other bead core, and a belt layer provided on the outer peripheral surface of the carcass ply. A method for manufacturing a pneumatic tire for a motorcycle, wherein a raw tire is formed by pasting a vulcanized tread rubber member, and the raw tire is vulcanized using a mold for vulcanization. The tread rubber member is divided into an end region, and the unvulcanized belt-like rubber is spirally wound in the tire circumferential direction as the tread rubber member of at least the tread side outer layer of the end region, and at least the tread side outermost layer of the center region with as the tread rubber member, the wound unvulcanized band-like rubber which is wider than the unvulcanized strip rubber in the tire circumferential direction, set the finished tire in a normal rim In the state of filling with normal internal pressure and no load, the distance in the tire axial direction from the tire equator plane is x, and the distance in the tire radial direction from the tread tread at the position of the distance x to the tread tread at the tire equator is When y is defined, the falling rate (y / x × 100) of the central region is configured to gradually increase as the distance from the tire equatorial plane increases.

  Here, “regular rim” refers to a standard rim in the applicable size specified in the 2004 version YEAR BOOK issued by JATMA, and “normal load” and “regular internal pressure” are similarly issued by JATMA. This refers to the maximum load and the air pressure for the maximum load in the applicable size and ply rating defined in the 2004 YEAR BOOK.

  When the TRA standard or ETRTO standard is applied at the place of use or manufacturing, the respective standards are followed.

  In the method for manufacturing a pneumatic tire for a motorcycle according to claim 1, as a tread rubber member of at least the tread side outermost layer in the end region of the tread, unvulcanized belt-like rubber is wound spirally in the tire circumferential direction ( Therefore, the manufacturing time (wrapping time of the belt-like rubber) is shorter than that of the spiral tread over the entire width of the tread, and an increase in manufacturing cost can be suppressed.

In addition, the tread thickness is made uniform because there is no wrinkle of the tread rubber due to narrowing at the time of molding the tire at the end of the tread where the drop rate is large. Further, as a tread rubber member in the central region having a lower drop rate compared with the end region of the tread, unvulcanized band-shaped rubber is wound in the tire circumferential direction (referred to as a band-wound tread). Manufacturing time can be shortened compared with the case of using a tread, and an increase in manufacturing cost is suppressed.

Therefore, according to the method for manufacturing a pneumatic tire for a motorcycle according to claim 1, it is possible to manufacture a pneumatic tire for a motorcycle excellent in uniformity , wear resistance, and durability over the entire tread .

According to a second aspect of the present invention, in the method for manufacturing a pneumatic tire for a motorcycle according to the first aspect , the unvulcanized belt-like rubber is overwrapped from the outer side in the tire axial direction toward the inner side. .

In the method for manufacturing a pneumatic tire for a motorcycle according to claim 2 , since the unvulcanized belt-shaped rubber is lap-wrapped from the outer side in the tire axial direction toward the inner side, the center region of the tread is moved from the central region to the end region during camber travel. Even when stress is applied to the end of the tire, the uneven wear performance of the pneumatic tire can be improved so that the endless portion of the portion that was a belt-like rubber before vulcanization does not have a wrinkled uneven wear.

A third aspect of the present invention is the method for manufacturing a pneumatic tire for a motorcycle according to the first or second aspect, wherein a boundary between the center region and the end region from the tire equatorial plane in the tire axial direction of the tread is provided. The tread rubber member is attached so that the distance to the surface gradually increases outward in the tire radial direction.

In the method for manufacturing a pneumatic tire for a motorcycle according to claim 3 , the tread rubber member is pasted so that the distance to the boundary surface between the central region and the end region gradually increases outward in the tire radial direction. Therefore, even if stress is applied from the central region to the end region of the tread during camber travel, no backspread or open splice is likely to occur at the boundary surface between the central region and the end region, and the durability is high.

  Note that the open splice is a peeling phenomenon along the joining interface that occurs when the joining interface between rubber and rubber, such as a joining interface between the same type of rubbers or a joining interface of different types of rubber, is subjected to repeated stress. .

According to a fourth aspect of the present invention, in the method for manufacturing a pneumatic tire for a motorcycle according to any one of the first to third aspects, the belt layer is a strip formed by covering at least one cord with rubber. Is spirally wound around the tire circumferential direction.

The method for manufacturing a pneumatic tire for a motorcycle according to claim 4 , wherein the belt layer is a spiral belt, and the tread end portion at the time of vulcanization molding even when there is a large circumferential length difference in the tire case before tread application As a result, the tread thickness is made uniform.

  In addition, by using a spiral belt as the belt layer, the carcass ply is reinforced more strongly and higher high-speed durability can be obtained.

According to a fifth aspect of the present invention, in the method for manufacturing a pneumatic tire for a motorcycle according to any one of the first to fourth aspects, the drop rate (y / x × 100) is maximum in the central region. The region is 10 to 35%, and the end region is a region that is on the outer side in the tire axial direction from the central region on both sides of the tire equatorial plane.

In the method for manufacturing a pneumatic tire for a motorcycle according to claim 5 , since the central region and the end region are appropriately defined by the drop rate, wrinkles and the like at the tread end during vulcanization molding are suppressed. The tread thickness is made uniform. For this reason, uniformity is good.

  In addition, in the case where a wide band-shaped rubber is wound around the central region, the winding time of the tread rubber member is shortened, so that the manufacturing cost can be suppressed.

According to a sixth aspect of the present invention, there is provided at least one layer of a carcass ply wound around a bead core disposed between the pair of bead portions in a toroidal shape from the inside to the outside, and positioned radially outward of the carcass ply. A pneumatic tire for a motorcycle having at least one belt layer and a tread located radially outward of the belt layer, the tread being divided into a central region and an end region, At least the tread side outermost layer in the end region is a spiral tread in which unvulcanized belt-like rubber is spirally wound in the tire circumferential direction and vulcanized, and at least the tread side outermost layer in the central region is a band wound tread unvulcanized band-like rubber than strip rubber is wide, which are vulcanized wound in the tire circumferential direction, assembled in a normal rim In the unloaded condition, the distance in the tire axial direction from the tire equatorial plane is x, and the distance in the tire radial direction from the tread tread at the position of the distance x to the tread tread at the tire equator Where y is y, the drop rate (y / xx100) of the central region gradually increases as the distance from the tire equatorial plane increases.

In the pneumatic tire for a motorcycle according to claim 6 , since at least the tread side outermost layer in the end region of the tread is a spiral tread, the manufacturing time is longer than the spiral tread over the entire width of the tread. The tread thickness is uniform because there is no wrinkle of the tread rubber due to narrowing at the time of molding the tire at the end of the tread where the time is short, the manufacturing cost can be suppressed, and the drop rate is large.

Therefore, in the pneumatic tire for a motorcycle according to claim 6 , the uniformity is good and chattering does not occur when the vehicle is running. In addition, by using the band-wound tread as the central region having a lower drop rate than the end region of the tread, the manufacturing time is shortened and the manufacturing cost is suppressed as compared with the case where the central region is a spiral tread. Furthermore, by adopting a spiral tread in the end region , uniformity, wear resistance and durability can be improved over the entire tread.

A seventh aspect of the present invention is the pneumatic tire for a motorcycle according to the sixth aspect , wherein the spiral tread is obtained by wrapping the unvulcanized belt-shaped rubber in an overlapping manner from the outer side in the tire axial direction toward the inner side. It is characterized by that.

In the pneumatic tire for a motorcycle according to claim 7 , even if stress is applied from the central region to the end region of the tread during camber travel frequently used in a motorcycle, the end of the portion that was a band-shaped rubber before vulcanization It is difficult to cause uneven wear in the shape of a wedge, and the uneven wear performance is high.

The invention according to claim 8 is the pneumatic tire for a motorcycle according to claim 6 or claim 7 , wherein a distance from the tire equator surface in the tire axial direction to a boundary surface between the central region and the end region is set. The boundary surface is inclined in the tire radial section so as to gradually increase outward in the tire radial direction.

The pneumatic tire for a motorcycle according to claim 8 , wherein the boundary surface is a tire radial cross section so that the distance to the boundary surface between the center region and the end region gradually increases outward in the tire radial direction. Therefore, even if a stress is applied from the central region to the end region of the tread during the camber traveling, the interface between the central region and the end region is unlikely to be crushed and open splices are generated, and the durability is high.

A ninth aspect of the present invention is the pneumatic tire for a motorcycle according to any one of the sixth to eighth aspects, wherein the belt layer includes a strip formed by rubber coating at least one cord. It is characterized by being a spiral belt that is spirally wound in the direction.

  When the belt layer is a spiral belt, since the expansion rate of the tire case at the time of vulcanization cannot be increased, the tire case before the tread is almost preliminarily shaped close to the product. For this reason, there is a large diameter difference (circumferential length difference) between the tire axial direction center region and the end region of the tire case, and it is necessary to affix a tread rubber on the tire case.

The pneumatic tire for a motorcycle according to claim 9 , wherein the belt layer is a spiral belt, and even when there is a large circumferential length difference in the tire case before the tread is applied, the wrinkles close to the end of the tread during vulcanization molding Etc. are suppressed, so that the tread thickness is made uniform.

  In addition, by using a spiral belt as the belt layer, the carcass ply is reinforced more strongly and higher high-speed durability can be obtained.

According to a tenth aspect of the present invention, in the pneumatic tire for a motorcycle according to any one of the sixth to ninth aspects, the drop rate (y / xx100) is a maximum of 10 to 35 in the central region. %, And the end region is a region that is on the outer side in the tire axial direction on the both sides of the tire equatorial plane than the central region.

In the pneumatic tire for a motorcycle according to claim 10 , since the center region and the end region are appropriately defined by the drop rate, wrinkles and the like at the tread end during vulcanization molding are suppressed, and the tread thickness Is made uniform. For this reason, uniformity is good.

  In addition to this, when the central region is a band-wound tread, the winding time of the tread rubber member is shortened, and thus the manufacturing cost is suppressed.

  As described above, according to the pneumatic tire for a motorcycle of the present invention, in a pneumatic tire for a motorcycle having a large tread drop rate, the uniformity, wear resistance and durability can be reduced while minimizing the manufacturing cost. It has the outstanding effect that it can improve property.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[First Embodiment]
In FIG. 1, a pneumatic tire 100 for a motorcycle according to the present embodiment includes at least one layer wound around a bead core 14 disposed between the pair of bead portions 12 in a toroid shape and wound around the bead core 12 from the inside to the outside. The carcass ply 16 (two layers in the illustrated example), at least one (three in the illustrated example) belt layer 18 positioned radially outward of the carcass ply 16, and the radial direction of the belt layer 18 And a tread 20 located outward.

  The belt layer 18 is a spiral belt in which a strip (not shown) formed by covering at least one cord with a rubber is spirally wound in the tire circumferential direction.

  Here, it is assembled to the regular rim, filled with regular internal pressure, and in the unloaded state, the distance in the tire axial direction from the tire equatorial plane CL is x, from the tread tread at the position of the distance x to the tread tread on the tire equatorial plane CL. Let y be the distance in the tire radial direction. A region where the drop rate (y / x × 100), which is the ratio of the distance y to the distance x, is 10 to 35% at maximum is defined as the central region 20A of the tread 20 and is more on both sides of the tire equatorial plane CL than the central region 20A. A region on the outer side in the tire axial direction is an end region 20B of the tread 20.

  In the end region 20B, the tread 20 is a spiral tread. The spiral tread is formed by unwrapping unvulcanized belt-like rubber 22 in a spiral shape so as to cover the belt layer 18 in the tire circumferential direction and on both sides of the tire equatorial plane CL from the outside in the tire axial direction to the inside. And is formed as a tread by a vulcanization mold.

  In addition, as FIG. 1 shows, the edge part area | region 20B is comprised so that it may reach to a tire maximum width position. This is because the tread 20 can come into contact with the road surface even when traveling at a large camber angle.

  A central region 20A of the tread 20 is a band-wound tread. The band-wound tread is formed by winding, for example, one turn of an unvulcanized band-shaped rubber 26 wider than the band-shaped rubber 22 in the tire circumferential direction, and is formed as a tread by a vulcanization mold.

  The boundary surface 20C between the center region 20A and the end region 20B has a tire radial cross section so that the distance from the tire equatorial surface CL to the boundary surface 20C in the tire axial direction gradually increases outward in the tire radial direction. Is inclined (inverted C in FIG. 1).

  Note that the central region 20A of the tread 20 may be a spiral tread similarly to the end region 20B. This is because the center region 20A of the tread 20 is a spiral tread, whereby the wear resistance and durability of the center region 20A are improved.

The configuration of the pneumatic tire 100 for a motorcycle according to the present embodiment is such that the distance from the tire equatorial plane CL to the tread maximum width position is the distance from the tread tread on the tire equatorial plane CL to the tread on the tread maximum width position. The end drop rate (Y / X × 100), which is the ratio of the tire radial direction distance Y, is as large as 50 to 95%, and is suitable for tires with a large tread end narrowing during vulcanization molding.
(Function)
Since the pneumatic tire 100 for a motorcycle uses the end region 20B of the tread 20 as a spiral tread, the manufacturing time (wrapping time of the belt-like rubber 22) is shorter than the spiral tread over the entire width of the tread 20, and the manufacturing cost is reduced. In the tread end where the drop rate is large, there is no wrinkle of the tread rubber due to narrowing during tire molding, and the tread thickness is made uniform.

  Therefore, in the pneumatic tire 100 for a motorcycle according to the present embodiment, the uniformity is good and chattering does not occur during actual vehicle travel. Further, by adopting the spiral tread in the end region 20B, the wear resistance and durability in the end region 20B are improved.

  Further, by using the band-wound tread with the central region 20A having a smaller drop rate compared to the end region 20B of the tread, the manufacturing time is shortened and the manufacturing cost is suppressed as compared with the case where the central region 20A is a spiral tread. Is done.

  Therefore, the pneumatic tire 100 for a motorcycle can also suppress an increase in cost in this respect, and can improve uniformity, wear resistance, and durability over the entire tread 20.

  As shown in FIG. 2, in the end region 20 </ b> B, the belt-like rubber 22 is spirally wound from the outer side in the tire axial direction toward the inner side. Therefore, when the camber travels frequently used in two-wheeled vehicles, For example, even if a stress acts in the direction of arrow F on the end region 20B due to friction, the end 22A of the portion that was the belt-like rubber 22 before vulcanization does not face the direction of the stress and follows the stress. Therefore, it is difficult for wrinkle-like uneven wear to occur at the end portion, and the uneven wear performance is high.

  Further, the boundary surface 20C between the center region 20A and the end region 20B is inclined in the tire radial cross section so that the distance from the tire equator surface CL to the boundary surface 20C gradually increases outward in the tire radial direction. Therefore, as shown in FIG. 2, even when the camber travels, when the stress acts on the boundary surface 20C in the direction of arrow F due to friction with the road surface 28, the boundary surface 20C follows the direction of the stress. Since it is in a state, the interface 20C is unlikely to cause a backlash or an open splice, and has high durability.

  When the belt layer 18 is a spiral belt, the tire case (not shown) during vulcanization cannot have a large expansion rate. Therefore, the tire case before the tread application is formed in a shape almost similar to the product in advance. For this reason, there is a large diameter difference (circumferential length difference) between the tire axial direction center region and the end region of the tire case, and tread rubber is pasted on the tire case.

  However, in the pneumatic tire 100 for a motorcycle, even when there is a large circumferential length difference in the tire case before tread application, the end region 20B of the tread 20 is a spiral tread so that the tread end during vulcanization molding It is possible to suppress wrinkles and the like in the tread and to make the tread thickness uniform. In this way, when the tire case has a large circumferential length difference, if the end region 20B is a spiral tread, the effect of uniforming the tread thickness becomes more remarkable.

Further, by using the belt layer 18 as a spiral belt, the carcass ply 16 is reinforced more strongly, and higher high-speed durability can be obtained.
[Second Embodiment]
3, in the pneumatic tire 200 for a motorcycle according to the present embodiment, the end region 20B of the tread 20 is configured in, for example, two layers, and for example, any layer is a spiral tread.

  However, in the tread side outermost layer 24, the belt-like rubber 22 is spirally wound from the outer side in the tire axial direction to the inner side as in the first embodiment, but in the lower layer 30 on the tire center side, On the contrary, the belt-like rubber 22 is spirally wound from the inner side toward the outer side in the tire axial direction, and the inclination direction of the belt-like rubber 22 is reversed between the tread side outermost layer 24 and the lower layer 30.

Since other parts are the same as those of the first embodiment of the present invention, the same parts are denoted by the same reference numerals and description thereof will be omitted.
(Function)
As shown in FIG. 4, in the tread side outermost layer 24 in the end region 20B, the belt-like rubber 22 is spirally wound from the outer side in the tire axial direction toward the inner side. Sometimes, even if stress is applied to the end region 20B in the direction of the arrow F due to friction with the road surface 28, the end of the portion that was the belt-like rubber 22 before vulcanization does not face the direction of the stress. Therefore, it is difficult for wrinkle-like uneven wear to occur at the end, and the uneven wear performance is high.

  Further, since the boundary surface 20C is inclined in the tire radial cross section so that the distance to the boundary surface 20C between the central region 20A and the end region 20B gradually increases outward in the tire radial direction, As shown in FIG. 4, when camber travels, for example, when stress is applied from the center region 20A to the end region 20B of the tread due to friction with the road surface 28, it is difficult to cause a backlash or an open splice on the boundary surface 20C. High nature.

  In addition, in the lower layer 30 of the end region 20B, the belt-like rubber 22 is wound in the opposite direction to the tread side outermost layer 24 and vulcanized, and the portion that was the belt-like rubber 22 before this vulcanization is removed from the road surface 28. Therefore, the tread rigidity is high and cornering at higher speed is possible.

In the illustrated embodiment, the overlapped belt-like rubber 22 is drawn so that there is a clear boundary. However, this is for the purpose of explanation, and when the same kind of unvulcanized rubber is vulcanized and molded side by side, The boundaries do not always remain clear. The same applies to the boundary surface 20C.
(Test example)
Under the conditions shown in Table 1, tires according to Example 1 (FIG. 1), Example 2 (FIG. 5), and a conventional example (not shown) were manufactured as trials, and the difference in rubber thickness on the tire circumference at the tread end portion, Tests were conducted on runout on the circumference, uniformity (indoor measurements), vibration and wear conditions (actual vehicle evaluation). The tire sizes are both 190 / 55R17.

  In FIG. 5, 300 is a pneumatic tire for a motorcycle according to the second embodiment, 302 is a bead portion, 304 is a bead core, 306 is a carcass ply, 308 is a belt layer, 310 is a tread, 310A is a central region, and 310B is an end portion. The region, 310C is a boundary surface, and 312 is a belt-like rubber.

  The rubber thickness difference on the tire circumference was measured by the thickness A in FIG. 1, and the runout on the circumference was measured in B in FIG. The same applies to Example 2 and the conventional example.

  In the test results shown in Table 2, the rubber thickness difference on the tire circumference and the runout on the circumference are indicated by an index with Example 1 as 100, and the larger the value, the better the result. .

  In addition, fluctuations in indoor measurements are compared with measurement data of uniformity, and are evaluated on a 10-point scale.

  The vibration in the actual vehicle evaluation is a feeling evaluation by the occupant, and the wear state is an evaluation by a tread observation evaluation method after traveling a predetermined distance. All values are out of 10 points.

  According to this test example, the rubber thickness difference on the tire circumference and the runout on the circumference for Example 1 and Example 2 were reduced by half compared to the conventional example, and the uniformity and The vibration is also improved over the conventional example.

  Regarding vibration, the evaluation of Example 2 is the best, but in Example 2, the winding direction of the belt-like rubber is reversely laminated to that of Example 1, so the wear state remains at the same level as the conventional example. ing.

  In Example 1, since the winding direction of the belt-like rubber is appropriate, both the vibration and the wear state are improved.

1 is a cross-sectional view of a pneumatic tire for a motorcycle according to a first embodiment. 1 is a cross-sectional view showing a ground contact state with a road surface when traveling with a camber using a pneumatic tire for a motorcycle according to a first embodiment. It is sectional drawing of the pneumatic tire for motorcycles concerning 2nd Embodiment. It is sectional drawing which shows a grounding state with the road surface when carrying out camber driving | running | working using the pneumatic tire for motorcycles concerning 2nd Embodiment. 3 is a cross-sectional view of a pneumatic tire for a motorcycle according to Embodiment 2. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 12 Bead part 14 Bead core 16 Carcass ply 18 Belt layer 20 Tread 20A Center area 20B End area 20C Boundary surface 22 Band-shaped rubber 24 Tread side outermost layer 26 Band-shaped rubber 100 Pneumatic tire for motorcycle 200 Pneumatic tire for motorcycle

Claims (10)

An unvulcanized tread rubber member is provided on the outer peripheral surface of a band assembly including at least a pair of bead cores, a carcass ply straddling one bead core and the other bead core, and a belt layer provided on the outer peripheral surface of the carcass ply. A method for producing a pneumatic tire for a motorcycle, comprising forming a raw tire by pasting and vulcanizing the raw tire using a vulcanization mold,
Dividing the tread into a central region and an end region;
As the tread rubber member of at least the tread surface side outermost layer of the end region, unvulcanized belt-like rubber is spirally wound in the tire circumferential direction,
As the tread rubber member of at least the tread surface side outermost layer of the central region, a non-vulcanized band-shaped rubber that is wider than the unvulcanized band-shaped rubber is wound in the tire circumferential direction,
The finished tire is assembled to the regular rim, filled with regular internal pressure, and in the unloaded state, the distance in the tire axial direction from the tire equator surface is x, and from the tread surface at the position of the distance x to the tread surface on the tire equator surface A pneumatic tire for a motorcycle characterized in that when the distance in the tire radial direction is y, the fall rate (y / xx100) of the central region gradually increases as the distance from the tire equatorial plane increases. Tire manufacturing method. The method for manufacturing a pneumatic tire for a motorcycle according to claim 1 , wherein the unvulcanized belt-shaped rubber is overlapped and wound from the outer side in the tire axial direction toward the inner side. Affixing the tread rubber member so that a distance from a tire equatorial plane in the tire axial direction of the tread to a boundary surface between the center region and the end region gradually increases outward in the tire radial direction; The method for manufacturing a pneumatic tire for a motorcycle according to claim 1 or 2 , wherein the pneumatic tire is used. The motorcycle air according to any one of claims 1 to 3, wherein a strip formed by covering at least one cord with rubber is spirally wound in the tire circumferential direction as the belt layer. A method for manufacturing a tire. The central region is a region where the drop rate (y / x × 100) is 10 to 35% at the maximum,
The motorcycle according to any one of claims 1 to 4 , wherein the end region is a region that is on an outer side in the tire axial direction with respect to the central region on both sides of the tire equator plane. A method of manufacturing a pneumatic tire. At least one layer of carcass ply wound around the bead core disposed between the pair of bead portions in a toroidal shape from the inside to the outside, and at least one belt layer positioned radially outward of the carcass ply And a pneumatic tire for a motorcycle having a tread located radially outward of the belt layer,
When the tread is divided into a central region and an end region,
At least the tread surface side outermost layer in the end region is a spiral tread in which an unvulcanized belt-like rubber is spirally wound in the tire circumferential direction and vulcanized.
At least the tread surface side outermost layer of the central region is a band-wound tread formed by vulcanizing and molding an unvulcanized band-shaped rubber that is wider than the belt-shaped rubber in the tire circumferential direction,
Assembled in a normal rim, filled with normal internal pressure, and in a no-load state, the distance from the tire equator plane to the tire axial direction is x, and the tire diameter from the tread tread at the position of the distance x to the tread tread at the tire equator The pneumatic tire for a motorcycle, wherein when the distance in the direction is y, the falling rate (y / xx100) of the central region gradually increases as the distance from the tire equatorial plane increases. The pneumatic tire for a motorcycle according to claim 6 , wherein the spiral tread is formed by wrapping the unvulcanized belt-shaped rubber from the outer side in the tire axial direction toward the inner side. The boundary surface is inclined in the tire radial cross section so that the distance from the tire equatorial plane in the tire axial direction to the boundary surface between the central region and the end region gradually increases outward in the tire radial direction. The pneumatic tire for a motorcycle according to claim 6 or 7 , wherein the pneumatic tire is a motorcycle. The belt layer has any one of claims 8 from claim 6, characterized in that strips formed by a rubber coating at least one cord is spiral belt formed by spirally wound in the tire circumferential direction The pneumatic tire for motorcycles described in 1. The central region is a region where the drop rate (y / x × 100) is 10 to 35% at the maximum,
The motorcycle according to any one of claims 6 to 9 , wherein the end region is a region which is on the outer side in the tire axial direction with respect to the central region on both sides of the tire equatorial plane. Pneumatic tire.

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