Pneumatic tyre for a two-wheeled vehicle

Abstract

The invention relates to a pneumatic tyre (1) for a two-wheeled vehicle, comprising a tyre tread (2), a tyre carcass, tyre sidewalls (3) and two bead regions (4) which each have a tyre bead having a core (5), wherein the two bead regions (4) each have a bead protection band (8) which is arranged axially outside the carcass as abrasion protection, wherein: • the tyre carcass is formed from a first carcass ply (6) and a second carcass ply (6') which each comprise reinforcements; • the second carcass ply (6') is arranged radially inside the first carcass ply (6) in a zenith (17) of the pneumatic tyre (1) for a two-wheeled vehicle and extends from the zenith (17) of the pneumatic tyre (1) for a two-wheeled vehicle over the tyre sidewalls (3) into both bead regions (4) and there wraps around each core (5) from axially inside to axially outside and ends in a second carcass ply end (7') under the bead protection band (8) of each bead region (4); • the first carcass ply (6) extends from the zenith (17) of the pneumatic tyre (1) for a two-wheeled vehicle over the tyre sidewalls (3) into the bead regions (4) and there wraps around each core (5) from axially inside to axially outside; • the first carcass ply (6) is guided from each bead region (4) in a carcass ply turn-up (61) over each tyre sidewall (3) and under the tyre tread (2); and • the two carcass ply turn-ups (61) overlap one another in the zenith (17) of the tyre (1), wherein the carcass ply turn-ups (61) extend over the zenith (17) and the tyre sidewalls (3) into both bead regions (4) and there end under the bead protection band (8) in a first carcass ply end (7).

Description

[0001] Two-wheel pneumatic tires

[0002] Description:

[0003] The invention relates to a pneumatic two-wheel tire, preferably a bicycle tire, in particular a racing bike tire, mountain bike tire, gravel bike / CX tire, or pedelec or e-bike tire, comprising a tread, a tire carcass, tire sidewalls, and two bead regions, each with a tire bead with a core. The two bead regions each have a chafer band arranged axially outside the carcass as abrasion protection. The tire carcass is formed from a first carcass ply and a second carcass ply, each having reinforcement members. The second carcass ply is arranged radially inside the first carcass ply in a zenith of the pneumatic two-wheel tire and extends from the zenith of the pneumatic two-wheel tire over the tire sidewalls into both bead regions, where it wraps around the respective core from axially inside to axially outside and ends in a second carcass ply end under the chafer band of the respective bead region.wherein the first carcass ply extends from the zenith of the pneumatic two-wheel tire over the tire sidewalls into the bead areas and there wraps around the respective core from axially inside to axially outside, wherein the first carcass ply is guided from the respective bead area in a carcass ply turn-up over the respective tire sidewall and under the tread, and wherein the two carcass ply turn-ups are arranged overlapping each other in the zenith of the tire.

[0004] Conventional pneumatic tires for two-wheelers, especially bicycle tires, are designed and optimized for rolling resistance, puncture protection, and mileage. These properties sometimes conflict with one another.

[0005] For example, EP 3 174 738 A1 discloses a racing bike tire with a two-ply carcass, with the high-cut edges of both carcass layers largely covering the sidewalls. Such a tire features reinforcement in at least part of the sidewall by four carcass layers. This construction enables high cut protection of the sidewall. However, the high use of carcass material in the sidewall area negatively impacts weight and rolling resistance.

[0006] A typical construction with a single-ply carcass is known, for example, from WO201 9 / 025953 A1 and is characterized by the carcass ply's upturns extending beyond the tire crown and overlapping below the tread. Such a construction is simple to manufacture, but has lower sidewall cut resistance and thus lower puncture resistance.

[0007] DE202020104281 U1 discloses a tire with a two-ply carcass, with the carcass rollovers of both carcass plies ending below the chafer. Such a tire is optimized for rolling resistance but offers low puncture protection.

[0008] A pneumatic two-wheel tire of this type is disclosed in DE 10 2021 201 322 A1. It has a two-layer carcass and overlapping carcass rollovers extending beyond the tire crown, creating a three-layer carcass composite in the tire sidewalls and a four-layer composite in the tire crown area. This construction offers a good balance between rolling resistance and puncture protection. However, for a training tire (all-season), cut and puncture protection are top priorities.

[0009] The invention is based on the object of providing a pneumatic two-wheel tire, preferably a bicycle tire, in which puncture resistance is improved while still maintaining good rolling resistance, which is nevertheless cost-effective to produce and is equally tubeless-ready and can be used on hookless rims.

[0010] This problem is solved by the carcass ply rollovers extending over the crown and the tire sidewalls into both bead areas, where they terminate in a first carcass ply end below the chafer. A particular advantage of the pneumatic two-wheel tire according to the invention is that the new tire construction significantly improves puncture resistance while maintaining good producibility. The tire structure remains the same as in the prior art, in particular according to DE 10 2021 201 322 A1, except for the additional material width of the carcass plies, but this significantly increases puncture protection. According to the invention, four layers of carcass plies are continuously present in the sidewall, as well as below the tread, formed by an overlapping arrangement of the first and second carcass plies and two further layers formed by the carcass rollovers. At the same time, the tire exhibits good rolling resistance.

[0011] Essential to the invention is that the first carcass ply is guided from the respective bead area in a carcass ply turn-up over the respective tire sidewall to under the tread, and from there over the opposite sidewall into the adjacent bead area to a first carcass ply end, where it terminates under the chafer at the respective first carcass ply end. At the same time, the second carcass ply also terminates under the chafer at its second carcass ply ends and is thus not guided from the respective bead area over the tire sidewalls to under the tread.

[0012] The tire has two axial halves. Thus, in each of the two axial halves of the tire, a carcass ply turnup running from the bead area towards the crown and a carcass ply turnup running from the crown to the carcass ply end are arranged overlapping one another in the area of ​​the tire sidewalls. Together with the plies formed by the first and second carcass plies, this provides reinforcement of each sidewall by four carcass ply thicknesses. The first carcass ply contributes three ply thicknesses and the second carcass ply contributes one ply thickness. By designing the sidewalls with four ply thicknesses, the cut resistance of the sidewall is significantly improved compared to a carcass with sidewall reinforcement of only two or three ply thicknesses.While reinforcing the sidewall with four carcass layers results in increased friction loss and requires additional carcass material, the trade-off between sidewall puncture resistance and high rolling resistance is resolved in favor of puncture resistance, which is particularly important for a puncture-resistant training tire.

[0013] By locating the first carcass ply ends beneath the chafer, they are also protected from detachment. This further improves the durability and puncture resistance of the two-wheel tire.

[0014] The new construction, with its two carcass plies wrapped around the core, allows for continued simple tire construction and also provides advantageous protection of the core from damage, especially compared to a carcass with only one carcass ply.

[0015] It has thus been found that a two-wheel tire, preferably a bicycle tire, having the construction according to the invention resolves the conflict of objectives between puncture resistance, in particular puncture resistance of the sidewall, and rolling resistance at a high level in favor of puncture resistance.

[0016] At the same time, the inventive design, by arranging the second carcass ply ends under the respective chafer, further ensures that there is no direct connection between the tire interior and the tire exterior through one of the two carcass plies. Likewise, the reinforcement members of the second carcass ply ending there are covered from the outside by the chafer at the second carcass ply ends. This prevents or greatly reduces the blowing off of air from the tire interior through the two carcass plies, particularly during tubeless operation, thus enabling a high level of airtightness of the tire, particularly during tubeless operation.

[0017] The first carcass ply terminates at the first carcass ply ends below the chafer. The first carcass ply ends can thus be arranged spatially between the chafer and a carcass ply turnup in the region of one bead, and spatially between the first carcass ply and the associated carcass ply turnup in the region of the other bead, so that the pneumatic two-wheel tire according to the invention is asymmetrical in the region of the carcass ply ends.

[0018] The second carcass ply terminates at the second carcass ply ends below the chafer of the respective bead area. The second carcass ply ends can each be spatially arranged between the respective chafer and a carcass ply turnup or between a first carcass ply end and a carcass ply turnup in the bead area.

[0019] The chafer serves as abrasion protection against the rim flange during tire operation, thus reducing exposure of the carcass reinforcement. The chafer may form or co-form an outer surface of the bead area designed as a contact surface with the rim. The chafer may cover the respective second carcass ply end from the outside.

[0020] The first carcass ply and the second carcass ply each have, as usual, parallel reinforcements embedded in elastomeric material. As usual, the reinforcements can form an angle of 40 degrees to 60 degrees with the direction of rotation U. The reinforcements of the first carcass ply and the second carcass ply can have opposite pitch angles.

[0021] Advantageous further developments of the invention are explained below

[0022] The tire has two axial halves. In an advantageous embodiment of the invention, it is provided that in each axial half, a carcass ply turnup running from the bead area towards the zenith and a carcass ply turnup running from the zenith to the carcass ply end are arranged overlapping one another in the area of ​​the tire sidewalls. The two carcass ply turnups thus overlap continuously across both sidewalls and in the zenith of the tire. The first carcass ply ends are each located in the other axial half, as is the starting point of the respective carcass ply turnup, which ends in the respective first carcass ply end. The carcass ply turnups thus run across both axial halves of the pneumatic two-wheel tire according to the invention. Axially between the two first carcass ply ends of the first carcass ply, there is thus continuous reinforcement by four ply thicknesses of the carcass.The first carcass ply is triple-layered, and the second carcass ply is single-layered. While such a construction can adversely affect rolling resistance, the tire's cut protection in the area of ​​the sidewalls and tread is greatly improved, resulting in significantly improved puncture resistance. This is particularly important for all-season tires and training tires for racing bikes.

[0023] This provides a pneumatic two-wheel tire that ensures advantageous puncture protection of the sidewalls and under the tread with minimal use of reinforcements, namely only two carcass inserts.

[0024] According to a further proposal of the invention, the first carcass ply ends or at least one carcass ply end end in the bead areas below the second carcass ply ends.

[0025] This ensures continued cut protection in the sidewall area and further improves the protection of the first carcass ply ends against detachment, as the first carcass ply ends are located beneath both the chafer strips and the second carcass ply ends. Due to the asymmetrical design in the bead area, the first carcass ply end is also positioned beneath the carcass ply turnup in one bead area.

[0026] In an advantageous development of the invention, it is provided that the chafer ends in a radially outer end at a first height of a maximum of 15 mm, preferably from 10 mm to 12 mm, measured relative to an outermost turning point of the reinforcement members of the second carcass ply wrapped around the core.

[0027] This low arrangement of both the chafer and the associated low arrangement of the second carcass ply ends means that the turn-ups of the second carcass plies are primarily located in an area that experiences little or no cyclic deformation during tire operation. This further reduces energy loss due to friction in the second carcass ply. Likewise, the material used for the chafer and the second carcass ply, and thus the tire's weight, is advantageously reduced.

[0028] To determine a height in the bead area, in particular the first height or the second height mentioned below, the cross-section of the pneumatic two-wheel tire can be bent up in such a way that the two carcass plies, coming from the zenith, are arranged largely in a straight line in the area of ​​the sidewall and merge into a wrap around the core that is largely symmetrical with respect to the core. In this arrangement, the respective height is measured relative to the outermost turnover point of an outer edge of the reinforcement members of the second carcass ply wrapped around the core, measured parallel to the largely straight-line arranged carcass plies. If the chafer has fibers, in particular a fabric, the fibers, in particular the fabric edge of the fabric, can specify the radially outer end of the chafer.Accordingly, the first carcass ply end and the second carcass ply end can be provided by ends of the reinforcement members, in particular by a fabric edge of the respective carcass ply.

[0029] Corresponding advantages with respect to the second carcass ply can be achieved by arranging the second carcass ply ends at a second height of a maximum of 13 mm, preferably from 8 mm to 10 mm, below the chafer, measured relative to an outermost turnover point of the reinforcement members of the second carcass ply wrapped around the core. Corresponding advantages also arise if the second carcass ply ends end in the respective bead area, in particular in front of the sidewall, coming from the core.

[0030] The chafer strip can be designed as a rubberized strip comprising fibers, in particular as a rubberized fabric strip. The fabric strip can be a muslin or nylon fabric.

[0031] In a further advantageous development of the invention, it is provided that the chafer is free of threads comprising twisted fibers which connect a radially outer end of the chafer and an inner end of the chafer.

[0032] In a further advantageous development of the invention, it is provided that the chafer is designed as a rubberized monofilament fabric.

[0033] The rubberized monofilament fabric reduces air leakage at the tire-rim contact surface particularly effectively, especially more effectively than a conventional chafer with a fabric made of threads made of multiple twisted fibers. This is because the monofilaments are largely individually embedded in the rubber coating, thus largely preventing air from escaping from the tire's interior to the tire's exterior via microchannels between the fibers of the chafer's threads.

[0034] This allows for particularly good airtightness of the tire mounted on a rim. This is particularly advantageous for tubeless tires. This allows the tire to be used without a tube without the need for additional, complex measures such as an inner liner, which often increase rolling resistance.

[0035] The chafer, constructed as a rubberized monofilament fabric, can be free of threads comprising twisted fibers that connect a radially outer end of the chafer and an inner end of the chafer. A further advantageous development of the invention provides for the carcass to be in direct contact with the tire interior. This enables a particularly lightweight tire and thus advantageous rolling resistance. For a tubeless tire, in particular a "tubeless ready" bicycle tire, sufficient airtightness can be ensured by the described measures, in particular the construction of a chafer constructed as a rubberized monofilament fabric.

[0036] In a further advantageous development of the invention, it is provided that the tire is a tubeless tire, in particular a “tubeless” tire or a “tubeless ready” tire.

[0037] Tubeless tires are tires designed for tubeless operation. Tubeless tires are specifically designed for tubeless operation.

[0038] Tubeless tires place increased demands on the airtightness of both the tire itself and the seal at the contact surface between the tire and the rim. A system in tubeless operation therefore comprises at least the tubeless tire and a rim, with the tubeless tire mounted on the rim and the system free of a tube. In tubeless operation of the tubeless tire, friction losses between the tube and tire are eliminated, so that the tire offers advantageous rolling resistance. Tube-related puncture causes are also eliminated. When using a tubeless tire in tubeless operation, the use of a sealing fluid, particularly a sealing milk, which has permeated into the tire interior between the tire and rim can improve the seal.

[0039] A tubeless tire can be a so-called "tubeless" tire, which is primarily or exclusively suitable and intended for use without a tube. A tubeless tire can often also be used without sealant.

[0040] A tubeless tire can also be a so-called "tubeless ready" tire, which is suitable and intended for use with or without a tube. A tubeless ready tire is typically used with a sealing fluid, especially a sealant, in tubeless operation. The tire and rim can be designed to seal directly against each other.

[0041] The invention is particularly advantageous for tubeless bicycle tires, in particular tubeless racing bike tires or tubeless mountain bike tires.

[0042] In a further advantageous development of the invention, it is provided that the bicycle tire is suitable and intended for operation with a tube, in particular a clincher tire. A system for operation with a tube thus comprises at least the bicycle tire and a rim, wherein the bicycle tire is mounted on the rim and a largely airtight tube is arranged in a tire interior enclosed by the tire and the rim. In a tire used with a tube, the air pressure is maintained via a largely airtight tube arranged in the tire interior between the tire and rim. Here, too, the new tire construction enables advantageously increased puncture protection.

[0043] A clincher tire is usually a wire or folding tire. The tire has a wire or folding core and is attached to the rim flange by the bead. A clincher tire is easy to install and remove. In the event of a flat, the damage can be easily repaired.

[0044] In a further advantageous development of the invention, it is provided that at least in one region of the sidewall, the two carcass plies, i.e. the first carcass ply and the second carcass ply, are the only plies comprising strength members. By omitting a further ply comprising strength members, a particularly thin and thus lighter and rolling resistance-optimized region of the sidewall is possible. In a further advantageous development of the invention, it is provided that a damping rubber insert made of a highly elastic rubber is arranged between the tread and the tire carcass, wherein the damping rubber insert in particular has a material thickness of between 0.2 mm and 1 mm.

[0045] This allows for greater riding comfort and improved rolling resistance by decoupling the fabric layers. The special thickness of the cushioning rubber insert significantly improves the riding comfort of the bicycle tire, as the tire adapts better to the road surface. Furthermore, the additional rubber insert increases puncture protection at the zenith.

[0046] Preferably, the damping rubber insert can be made of a highly elastic rubber with a rebound material value between 70 and 80. This rebound material value achieves optimal driving comfort while simultaneously not increasing the tire's rolling resistance.

[0047] In a further advantageous development of the invention, it is provided that a protective layer made of a particularly tear-resistant rubberized fabric, preferably a particularly tear-resistant rubberized fabric comprising fibers made of polyethylene terephthalate - polyacrylate, or of a rubber layer is arranged between the tread and the tire carcass.

[0048] The protective layer ensures optimal puncture protection at the apex of the pneumatic two-wheel tire, preferably a bicycle tire. The particularly tear-resistant rubberized fabric containing polyethylene terephthalate-polyacrylate fibers can be a rubberized fabric containing or consisting of Vectran fibers. The rubber layer can have a maximum thickness of 6 mm, measured radially at the apex of the tire.

[0049] In a further advantageous development of the invention, it is provided that the tire is a bicycle tire, in particular a racing bike tire, a gravel / CX tire, a mountain bike tire, or a tire for a bicycle having an electric motor for driving the bicycle. However, the new tire construction is suitable for use in all bicycle segments.

[0050] The tire construction according to the invention can be used for racing bike tires. A racing bike tire typically has a maximum tire width of 35 mm and features a low tread profile specific to racing bikes.

[0051] The tire construction according to the invention, particularly for tubeless tires, is also ideally suited for gravel / CX tires and mountain bike tires. Gravel and CX tires generally have a minimum tire width of 32 mm, especially 40 mm, and often a pronounced tread pattern. Mountain bike tires generally have a minimum tire width of 45 mm, especially 60 mm, and a pronounced tread pattern. Even with these profiled tires, aspects such as rolling resistance and high puncture protection are becoming increasingly important. In particular, tubeless tire operation can be advantageous, as this reduces the susceptibility to punctures and allows such a tire to be run at comparatively lower air pressure.

[0052] The new tire design is also ideal for use on bicycles equipped with an electric motor. In such applications, high puncture protection is advantageous, as it increases the bicycle's reliability.

[0053] This could be a tire for an electric bike. A tire for an electric bike can meet the "ECE-R75" test standard. Its specific suitability for electric bikes is often indicated by the designation "E-Bike Ready 50."

[0054] This can also be a tire for a pedelec, where the drive is at least partially assisted by the electric motor. The specific suitability for a pedelec is often indicated by the designation "E-Bike Ready 25."

[0055] In a further advantageous development of the invention, it is provided that the tire is a motorcycle tire, in particular an electric scooter tire. A motorcycle tire or an electric scooter tire featuring the novel design can also contribute to improved vehicle reliability through the advantageous puncture protection.

[0056] Further features, advantages, and details of the invention will now be explained in more detail with reference to the schematic drawings, which illustrate an exemplary embodiment. Shown are:

[0057] Figure 1 shows a two-wheel pneumatic tire according to the invention in cross section;

[0058] Figure 2 shows a section of the two-wheel pneumatic tire in cross section.

[0059] Figure 1 shows the essential tire components of a pneumatic two-wheel tire 1 in a cross-sectional view. It is a pneumatic two-wheel tire 1, preferably a bicycle tire, with a tread 2, a tire carcass, tire sidewalls 3, and two bead regions 4, each with a tire bead with a core 5. The two bead regions 4 each have a chafing protection strip 8 arranged axially outside the carcass as abrasion protection.

[0060] The tire carcass is formed from a first carcass ply 6 and a second carcass ply 6', each comprising reinforcement members. The reinforcement members are generally arranged parallel to one another within the respective carcass ply and at an angle to the circumferential direction U of 40 degrees to 60 degrees. The reinforcement members of the two carcass plies 6, 6' can have opposing pitch angles. The tire 1 has two axial halves 20, which are symmetrical to one another, at least with respect to the carcass plies 6, 6'.

[0061] The second carcass ply 6' is arranged in a zenith 17 of the tire 1 radially inside the first carcass ply 6. It extends from the zenith 17 of the pneumatic two-wheel tire 1 over the tire sidewalls 3 into both bead regions 4 and there wraps around the respective core 5 from axially inside to axially outside and ends in a second carcass ply end 7' under the chafer 8 of the respective bead region 4. The first carcass ply 6 extends from the zenith 17 of the tire 1 over the tire sidewalls into the bead regions 4 and there wraps around the respective core from axially inside to axially outside.

[0062] The pneumatic two-wheel tire 1 is characterized in that the first carcass ply 6 is guided from the respective bead region 4 in a carcass ply turnup 61 over the respective tire sidewall 3 under the tread 2 through the axially opposite sidewall to a first carcass ply end 7 and ends there under the chafer 8 in the first carcass ply end 7. Thus, in both axial halves 20 of the pneumatic two-wheel tire 1 in the region of the sidewalls 3, in particular radially between the second carcass ply end 7' and a tread end 21, the sidewall 3 is reinforced by four ply thicknesses of the carcass, with the first carcass ply 6 contributing three ply thicknesses and the second carcass ply 6' contributing one ply thickness.

[0063] The first carcass ply 6 ends in the first carcass ply ends 7 below the chafer 8 and radially below the second carcass ply end 7'. The first carcass ply end 7, which ends in the left axial half 20 of the drawing, lies spatially between the chafer 8 and the first carcass ply turnup 61. The first carcass ply end 7, which ends in the right axial half 20 of the drawing, however, lies spatially between the carcass ply turnup 61 and the first carcass ply 6. A first straight line 18 oriented perpendicular to the second carcass ply 6' runs radially below a second straight line 19 oriented perpendicular to the carcass ply turnup 61.

[0064] The chafer 8 can terminate in a radially outer end 12 at a first height 13 of a maximum of 15 mm, preferably from 10 mm to 12 mm, measured relative to an outermost turn-over point 14 of an outer edge of the reinforcement members of the second carcass ply 6' wrapped around the core 5. Alternatively or additionally, the second carcass ply ends 7' of the second carcass ply 6' can be arranged at a second height 15 of a maximum of 13 mm, preferably from 8 mm to 10 mm, measured relative to an outermost turn-over point 14 of the reinforcement members of the second carcass ply 6' wrapped around the core 5. The dimensions of the first height 13 and the second height 15 are illustrated in Figure 2. The chafer 8 is designed as a rubberized band comprising fibers, in particular as a rubberized fabric band.

[0065] The fibers, in particular the fabric edge of the fabric, can define the radially outer end 12 of the chafer 8. Particularly for tubeless operation, the chafer 8 can be free of intertwined fiber threads connecting a radially outer end 12 of the chafer 8 and an inner end 16 of the chafer 8. In Figures 1 and 2, the chafer 8 is embodied, by way of example, as a rubberized monofilament fabric.

[0066] The second carcass ply ends 7' of the second carcass ply 6' can end in the bead area 4, in particular coming from the core 5 in front of the sidewall 3.

[0067] The carcass is in direct contact with the tire interior 10. The tire 1 is, in particular, free of an inner liner. However, advantages according to the invention can also be achieved by a pneumatic two-wheel tire 1 that has an additional layer, in particular an inner liner, between the tire interior 10 and the carcass.

[0068] As shown, at least in one region of the sidewall 3, in particular from the radial outside adjoining the bead band 8, the two carcass inserts 6, 6' can be the only inserts having reinforcements.

[0069] As shown, a damping rubber insert 9 made of a highly elastic rubber can be arranged between the tread 2 and the tire carcass, wherein the damping rubber insert 9 has a material thickness of between 0.2 mm and 1 mm in particular. Preferably, the damping rubber insert can be made of a highly elastic rubber with a rebound material value of between 70 and 80. A protective layer (not shown) comprising a particularly tear-resistant rubberized fabric, preferably a rubberized fabric comprising fibers made of polyethylene terephthalate-polyacrylate, can be arranged between the tread 2 and the tire carcass. Alternatively, the protective layer can also be formed from a rubber layer with a maximum thickness of 6 mm, measured in the radial direction rR at the tire zenith 17.

[0070] The tires depicted are tubeless tires, specifically "tubeless" tires or "tubeless ready" tires. The tire may be suitable, intended, and used for tubeless operation. However, a tire designed for use with a tube, specifically a clincher tire, may also have an advantageous design with corresponding features.

[0071] The tires depicted are racing bike tires. However, other tires, particularly gravel, CX, and mountain bike tires, or tires for bicycles with an electric motor to power the bicycle, can also be designed accordingly. Motorcycle tires, especially electric scooter tires, can also feature the advantageous design depicted.

[0072] Figure 1 shows a particularly puncture-resistant tire 1. The first two carcass ply turnups 61 are arranged overlapping one another both in the area of ​​the sidewalls 3 and in the zenith 17 of the tire 1. Each of the two carcass ply turnups 61 extends from a bead area 4 in one axial half 20 of the pneumatic two-wheel tire 1 over the adjacent sidewall 3 and below the tread 2 as well as over the opposite sidewall 3 and ends in the respective first carcass ply end 7 in the other axial half 20 of the tire. In the area of ​​the sidewalls and the zenith 17 of the tire, the tire 1 is thus reinforced by four ply thicknesses of the carcass, as shown.

[0073] Figure 2 illustrates the dimensioning of the first height 13 and the second height 15. To determine the first height 13 and the second height 15, the two-wheel pneumatic tire 1 can be bent up in its cross-section such that the two carcass plies 6, 6', coming from the zenith 17, are arranged largely in a straight line in the region of the sidewall 3 and transition into a largely symmetrical wrap around the core 5 with respect to the core 5. This can be a section of the tire of Figure 1, with the two-wheel pneumatic tire 1 being bent up accordingly in its cross-section. In this arrangement, the first height 13 and the second height 15 are measured relative to the outermost turnover point 14 of an outer edge of the reinforcement members of the second carcass ply 6' wrapped around the core 5 and measured parallel to the carcass plies 6, 6' arranged largely in a straight line in the region of the sidewall 3.

[0074] List of reference symbols:

[0075] 1 two-wheel pneumatic tire

[0076] 2 treads

[0077] 3 side wall

[0078] 4 Bead area

[0079] 5 core

[0080] 6 first carcass ply

[0081] 6' second carcass ply

[0082] 7 first carcass ply end

[0083] 7' second carcass end

[0084] 8 chafer strip

[0085] 9 Rubber insert

[0086] 10 Tire interior

[0087] 11 Tire exterior

[0088] 12 radial outer end of the chafer

[0089] 13 first height

[0090] 14 outermost turning point

[0091] 15 second height

[0092] 16 radial inner end of the chafer

[0093] 17 Zenith

[0094] 18 first straight

[0095] 19 second straight

[0096] 20 axial half

[0097] 21 Tread end

[0098] 61 Carcass ply turn-up rR radial direction aR axial direction

[0099] U Direction of rotation

Claims

Patent claims:

1. Two-wheel pneumatic tyre (1) with a tread (2), a tyre carcass, tyre sidewalls (3) and two bead regions (4), each with a tyre bead with a core (5), wherein the two bead regions (4) each have a bead protection band (8) arranged axially outside the carcass as abrasion protection, • wherein the tire carcass is formed from a first carcass ply (6) and a second carcass ply (6'), each comprising reinforcement members, • wherein the second carcass insert (6') is arranged in a zenith (17) of the two-wheel pneumatic tire (1) radially inside the first carcass insert (6) and extends from the zenith (17) of the two-wheel pneumatic tire (1) over the tire sidewalls (3) into both bead regions (4) and there wraps around the respective core (5) from axially inside to axially outside and ends in a second carcass insert end (7') under the chafer (8) of the respective bead region (4), • wherein the first carcass insert (6) extends from the zenith (17) of the pneumatic two-wheel tire (1) over the tire sidewalls (3) into the bead areas (4) and there wraps around the respective core (5) from axially inside to axially outside, • wherein the first carcass ply (6) is guided from the respective bead area (4) in a carcass ply turn-up (61) over the respective tire sidewall (3) and under the tread (2) and • wherein the two carcass ply upturns (61) are arranged overlapping one another in the zenith (17) of the tire (1), characterized in that the carcass ply upturns (61) extend over the zenith (17) and the tire sidewalls (3) into both bead regions (4) and end there under the chafer (8) in a first carcass ply end (7).

2. Two-wheel pneumatic tire (1) according to claim 1, characterized in that the tire (1) has two axial halves (20) and that in each axial half (20) a carcass ply turn-up (61) running from the bead region (4) in the direction of the zenith (17) and a carcass ply turn-up (61) running from the zenith (17) to the carcass ply end (7) are arranged overlapping one another in the region of the tire sidewalls (3).

3. Two-wheel pneumatic tire (1) according to at least one of the preceding claims, characterized in that the first carcass ply ends (7) end in the bead regions (4) below the second carcass ply ends (7').

4. Two-wheel pneumatic tire (1) according to at least one of the preceding claims, characterized in that the chafer (8) ends in a radially outer end (12) at a first height (13) of a maximum of 15 mm, preferably from 10 mm to 12 mm, measured relative to an outermost turn-over point (14) of the reinforcement members of the second carcass ply (6') wrapped around the core (8).

5. Two-wheel pneumatic tire (1) according to at least one of the preceding claims, characterized in that the chafer (8) is designed as a rubberized monofilament fabric.

6. Two-wheel pneumatic tire (1) according to at least one of the preceding claims, characterized in that the carcass is in direct contact with a tire interior (10).

7. Two-wheel pneumatic tire (1) according to at least one of the preceding claims, characterized in that it is a tubeless tire (1), in particular a "tubeless" tire or a "tubeless ready" tire.

8. Two-wheel pneumatic tire (1) according to at least one of the preceding claims, characterized in that it is a bicycle tire (1) for operation with a tube, in particular a clincher tire.

9. Two-wheel pneumatic tire (1) according to at least one of the preceding claims, characterized in that at least in one region of the sidewall (3) the first carcass ply (6) and the second carcass ply (6') are the only plies having reinforcements.

10. Two-wheel pneumatic tire (1) according to at least one of the preceding claims, characterized in that between the tread (2) and the tire carcass a damping rubber insert (9) made of a highly elastic rubber is arranged, wherein the damping rubber insert (9) in particular has a material thickness between 0.2 mm and 1 mm.

11. Pneumatic two-wheel tire (1) according to at least one of the preceding claims, characterized in that a protective layer made of a particularly tear-resistant rubberized fabric, preferably a particularly tear-resistant rubberized fabric comprising fibers made of polyethylene terephthalate - polyacrylate, or of a rubber layer is arranged between the tread (2) and the tire carcass.

12. Two-wheel pneumatic tire (1) according to at least one of the preceding claims, characterized in that it is a bicycle tire (1), in particular a racing bike tire (1), a mountain bike tire or a tire for a bicycle having an electric motor for driving the bicycle.

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