Like other models of this brand, the summer tire Nitto NT421A was developed by specialists of the Japanese company Toyo. The Japanese tire giant created a new brand, under which tires are released, addressed to motorists who are not afraid to try something new. The products of this brand, including this tire, are used to "test" various technological solutions, which are then used in the models of the "parent" brand.
Wear sensors
One of such solutions was the wear sensors of the tread. But, unlike tires of many other brands, the developers changed their shape and location. They are applied in the form of numerous points on the walls of longitudinal drainage grooves. Externally, the wear sensors look like a dotted line leading from the working surface of the tread downwards. This solution has one significant advantage, namely, the ability to more accurately track the degree of tire wear, which allows, for example, to notice its unevenness much earlier. As a rule, such behavior of the tire is a consequence of a malfunction in the car's suspension, the elimination of which at an early stage of its development will be much cheaper.
Intersecting 3D lamellas
In some markets, this tire is positioned as a model that can be used both in summer and winter. The versatility of application is largely due to the use of lamellas. These tread elements have several features in both design and arrangement. The walls of the lamellas are made in a three-dimensional design, and they themselves intersect with each other. This solution allowed to improve many of the tire's handling characteristics. First of all, this is the traction on a slippery surface, provided by a large number of edges that have a significant length and are located at different angles to the direction of movement. At the same time, the three-dimensional design of the lamella walls, when they open, limits the mobility of the blocks, which has a positive effect on handling, resistance to uneven wear, and rolling resistance.
Reinforced shoulder areas
One of the key features of the tire is the reinforced construction of the shoulder areas of the tread. The breaker located directly under it is equipped with additional cords made of synthetic material. They are wide meshes located under the shoulder areas. The presence of such a rigid "substrate" additionally improves the efficiency of these functional areas, which, in turn, has a positive effect on a number of operational properties of the tire, one way or another dependent on the speed of transmission of transverse accelerations when maneuvering and turning. First of all, this is the clarity of feedback, course stability, traction, resistance to uneven wear, and rolling resistance.
Stability-enhancing blocks
Among the many other features of the asymmetric tread design, it is worth noting the execution of the blocks located in the "shoulder" area. They have a composite structure, divided into two parts by a wide longitudinal groove. The stiffness of the blocks located closer to the edge of the tread is ensured by their massive size and transverse arrangement. In turn, the stability of the elements located in the central part of the tread is achieved by the presence of bridges. They combine the blocks into groups, two in each of them. This design significantly improves the tire's traction when cornering, and due to the very long traction edges, it reduces the braking distance.
Main features of the summer tire Nitto NT421A
- wear sensors of the tread, allowing for more accurate readings;
- intersecting 3D lamellas that improve traction on slippery surfaces;
- composite structure of the shoulder area blocks, improving stability when maneuvering, reducing braking distance.
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