What does 58P mean on a motorcycle tire?

[JonathanMarie]

Motorcycle tire 58P, where 'P' refers to the speed rating, indicating the tire's maximum speed is 150 km/h, and '58' represents the load index of the tire. Tire marking methods: There are various ways to denote tire specifications, with four common types in the market: British, German, metric, and American systems. Here's a brief explanation of these four: The British system, used by former British colonies, uses inches as the unit. For example, 4.00H184PR means the width is 4 inches, suitable for speeds below 210 km/h, with a tire rim diameter of 18 inches and a 4-ply rating. Metric tire markings: These provide a more comprehensive description of tire characteristics. Similar to the German system but omits the '-' sign for low-pressure tires, replacing it with 'R' to denote radial tires. For example, the rear tire of an FZR400 is marked as 140/60R1864H, where 'R18' indicates that the tire is a radial tire.

[EllieLee]

In the motorcycle tire marking 58P, 58 is the load index, indicating that a single tire can bear a weight of 236 kilograms, and P represents the maximum speed rating of 150 kilometers per hour. When I last changed tires for my beloved bike, I paid special attention to this parameter because overloading can cause excessive tire heating, which is particularly dangerous when riding mountain roads in summer. Actually, there are also size codes on the tire sidewall, such as 120/70ZR17. Although the combination of numbers and letters may seem complex, just remember a few key points: the first three digits represent width, the next two digits represent the aspect ratio, the letter indicates the construction type, and the last number is the rim size. It is recommended that riders at least retain the original factory specifications when changing to new tires, and for long-distance trips, it's better to choose higher specifications.

[DelHenry]

The code 58P on tires is actually a performance combination indicator, which many motorcycle customers overlook, as I've noticed over my decade of motorcycle repair experience. The number 58 corresponds to a load capacity of 236 kilograms per tire, while the letter P indicates a maximum safe speed of 150 km/h. These two values must be matched in use. If you frequently carry passengers or climb hills, it's advisable to choose a tire with a higher load index. Here's a handy tip: when inspecting tires, always check the DOT manufacturing date code on the sidewall. The last two digits represent the year, and the first two digits indicate the week of production. Even if the tread depth appears sufficient, tires older than five years should be replaced, as aged rubber experiences a dramatic loss of wet-weather grip.

[EvanLynn]

As a motorcycle owner who frequently goes on touring rides, I pay special attention to tire parameters. In the 58P specification, P is the speed symbol, equivalent to a maximum speed limit of 150km/h, while 58 represents a maximum load capacity of 236kg. This combination is commonly used for street bikes, but it's important to note that the specifications of both tires on the same axle must be completely identical. Mixing different specifications can lead to abnormal wear. In fact, the tire sidewall also displays traction and temperature ratings. For example, AA grade offers the best wet grip, followed by A grade. My tire selection experience: If you frequently ride in wet or slippery areas, prioritize tires with higher traction ratings, as performance is more important than visually appealing tread patterns.