If you have ever seen ZR marked on the side of your tire and wondered it means, we are here to tell you! These letters represent the tires speed rating, which in the case of ZR signified the tire is designed for speeds over 150mph.
In this blog post, we will explain everything that you need to know about speed ratings on tires.
What Does ZR Mean on a Tire?
The ZR on a tire sidewall represents a tires “speed rating.” The speed rating of a tire is the maximum speed that a tire can safely achieve.
ZR signifies that the particular tire is capable of speeds above 150 mph.
The lettering system has since been refined further by the addition of other letters in recent years. These additional letters help to identify a tire’s speed capabilities even further.
Prior to the introduction of the improved ratings such as W, Y, and ZR in 1990, tire manufacturers used “ZR” to indicate high-performance tires. Although this has since lost its significance in modern times, the “ZR” label continues to persist in the inventories of shops and tire manufacturers.
What Is A Tire Speed Rating?
A tire’s speed rating is the maximum speed that a tire can safely achieve. The speed rating of a tire is usually represented by a letter on the sidewall of the tire. These will vary from tire to tire depending on their construction and design.
Where Can I Find My Tire Speed Rating?
The speed rating of a tire can be found on the sidewall of the tire and is represented by a letter. The letter usually comes after the tire size code and the load rating. For example, if you see a tire size that looks like this: P215/60R15 96Y, the Y indicates the tires speed rating.
This letter will differ depending on the tire and its capabilities and can be a range of different letters. When picking a tire for your car, it is important to pick a tire that will be able to handle the speeds that your car is capable of achieving.
How Is A Tire Speed Rating Determined?
Tire speed ratings are determined by the manufacturer through a series of tests. These tests are conducted in a controlled environment and help to simulate different driving conditions.
Tires with a higher speed rating will be able to withstand the stress of high speeds better than those with a lower speed rating.
Why is speed rating important?
The speed rating of a tire indicates the maximum safe speed at which the tire can operate under specific load and inflation conditions. Using tires with a lower speed rating than what your vehicle requires can potentially lead to tire failure, reduced handling and compromised safety.
You can always use a tire with a higher speed rating than needed for your vehicle, but you should never use a tire with a lower speed rating.
What Are The Different Tire Speed Ratings?
There are a few different tire speed ratings. Here is a list of common speed ratings and their corresponding maximum speeds:
Is there a difference between ZR tires and R tires?
ZR used to mean a tire is suitable for vehicles that can exceed 149 pmh, however this has now been updated to V, W and Y tires, making ZR mostly irrelevant. If a tires speed rating is R then it is only rated for 106 mph.
However, it is likely that the R referred to here is in regards to the tires structure, signifying that the tire is a radial construction tire.
Does ZR mean Run-Flat tire?
No, a run flat tire is signified by the symbols ZRF (Z-rated run-flat) which is a very uncommon tire.
Conclusion
So now you know the answer to “What Does ZR Mean on a Tire” and that it means a tire is rated for speeds over 150 mph, be sure to look out for the speed rating when purchasing new tires. This is especially true for vehicles capable of excessive speeds as high performance tires are required.
We hope you enjoyed this article and found it informative. If you have any questions then please leave a comment below or get in touch via email or through social media and we will read and respond to every comment, email or question. Thanks for reading!