The axle on which this tyre is recommended to be mounted.
In the vast majority of modern motorcycles, the
front wheel is steering, and the
rear wheel is driving; in addition, the rear wheel usually bears more weight. Accordingly, the features of the work of both axes will also be different. So, the front tyre has to turn in different directions along the course, and the rear one has to be subjected to increased loads in terms of weight and twisting along the main axis of rotation, in addition, it must “cling” well to the road in order to avoid slipping. In light of all this, putting tyres on a "non-native" axle is highly undesirable: it will work in an emergency mode, and the consequences can be very deplorable. At the same time, there are
universal models suitable for both the front and rear axles (although they can cost more than specialized ones, and at an equal cost, they can be inferior to them in terms of individual characteristics).
The speed rating characterizes the maximum speed at which the tyre maintains performance, in other words, the highest speed at which you can safely drive when using this tyre in normal mode (on the “native” axle, with normal load, etc.). This parameter is indicated by Latin letters, each of which corresponds to its own maximum speed value — for example, a value of 210 km/h is denoted as H. The most modest modern tyres, used mainly for scooters and motocross motorcycles, have the index J (100 km/h), and in high-speed sports models there are models of the
W level (270 km/h).
You should choose a tyre for this parameter based on the recommendations of the motorcycle manufacturer, and if there are no such recommendations, then with a margin of at least 10-15 km/h in excess of the maximum speed with which you plan to ride; this will give an additional guarantee of safety in case of emergency situations. It is technically OK for most motorcycles to use tyres that are less fast than recommended, but in fact this should not be done. And the point is not only that the driver will have to limit the speed of movement — such tyres are generally less durable than high-speed ones and may not tolerate sharp accelerations well.
