The Z speed rating is shown on the side of a tire, along with the load index and tire size. A tire rated for 149 mph or more will have a “Z” in its size designation. For example, it might be listed as 225/50ZR16 91W.
This tire fits wheels that are 16 inches in diameter and has a section width of 225 millimeters. The “Z” indicates that the tire is rated for speeds above 149 mph, while the “91W” indicates that the tire can carry a maximum load of 1,389 pounds at 168 mph.
Tires with speed ratings lower than 149 mph are sometimes rated with a Y speed rating, which appears as a “Y” after the load index in the size designation. This indicates that the tire can safely handle speeds up to 186 mph without failure.
What does 225 45R17 91W mean?
- 225 = the width in millimeters (mm) of the tire from sidewall to sidewall
- 45 = the aspect ratio, which is the height from the rim to the top of the tire; in this case 45% of 225mm
- R = radial construction (almost every tire on the road today is a radial)
- 17 = rim diameter in inches
- 91W = load index and speed rating
225/45R17 is the size of your tire. The 225 part means the width of your tire from sidewall to sidewall is 225 millimeters. The 45 part means that your sidewall height, from rim to tread, is 45% of 225mm, or 101.25 mm.
R stands for radial construction. 17 is the diameter, in inches, of the rim. 91W is the load rating index and speed rating index, or the maximum weight and speed that a tire can carry.
225 is the width in millimeters. 45 is the aspect ratio. This is a percentage, so 45 means the tire’s height is 0.45 times its width. In this case, that’s 101.25 mm.
R tells you what kind of tire this is. R means radial, which is the most common type of tire used on passenger vehicles today. Other types of tires are built in different ways and aren’t compatible with most modern cars and trucks.
17 is the size of the wheel rim, in inches. 91W indicates the load index and speed rating. The load index tells you how much weight each tire can support when appropriately inflated (see chart below).
The speed rating tells you the maximum speed at which the tire can carry a load corresponding to its load index — see chart below for more information on speed ratings here, too!
What does W mean on a tire?
The “W” in a tire size refers to winter and makes it easy to identify tires made for harsh weather.
The “W” stands for winter, which is important because it tells you what season the tire is designed for. If you live in an area that sees cold temperatures and snow during the winter, then a tire with a “W” rating will be suitable for your vehicle.
Tires with a “W” rating are designed to provide better handling on snow-covered roads than tires without a W rating, including all-season tires.
Snow tires have deep treads, which helps them grip snow and ice more effectively than most all-season tires.
W-rated tires also have softer rubber compounds that offer more grip when the temperature drops below 45 degrees Fahrenheit. The letter “W” in a tire size represents the tire’s speed rating.
This is the maximum speed that the tire is capable of. For example, a tire with a W rating means that the maximum speed is 168 mph.
The speed rating tells you the speed at which the tire can be safely operated for extended periods. A Z-rated tire should not be driven at speeds over 149 mph for an extended period.
What does 94w mean on a tire?
94w means 94 load rating and W speed rating. The 94 load rating is the weight that each tire can support. This tire can support 1,477 lbs. or 679 kgs.
94w is the speed rating of a tire. It means that your tire can safely handle speeds up to 270 km/h (168 mph).
This is not to be confused with the load index. The load index indicates how much weight a tire can carry.
The 94 in the tire size refers to the load index. The load index is a numerical code associated with the maximum weight that a tire can support when properly inflated. This measurement is given in pounds or kilograms and varies depending on the size of the tire.
The other number in the series, a W, stands for winter tires. Winter tires are designed to be used only when temperatures drop below 45 degrees Fahrenheit.
Winter tires come with deeper tread depths than summer tires to cut through snow and slush but are more expensive than all-season tires.
The first number is the load index, in this case, 94, or the maximum load of 1615kg per tire. The second letter is a speed rating, in this case, W or 270 km/h. The third number is the width of the tire in millimeters.
The next number is the aspect ratio of width to sidewall.
What is the 91W speed rating?
91W is a speed rating that indicates the tire’s maximum allowable speed when properly inflated. The speed rating system, developed by the Uniform Tire Quality Grading System (UTQGS), ensures that tires meet vehicle manufacturers’ handling requirements.
Tires with a 91W speed rating can travel at speeds up to 168 mph (270 km/h) under ideal conditions. However, driving at such speeds is extremely dangerous and should not be attempted.
- 91W = Load Index 91 = 1356 lbs.
Load ranges for passenger tires are P, LT, and Commercial.
Passenger tires can vary widely in weight limits, some as low as 1000 lbs. on a 235-75-15 (the maximum tire size for the 5 on 4-1/2 bolt pattern) to over 5000 lbs. on a 375-40R-20.
The Light Truck tires can have load ranges from 1200 lbs. to well over 5000 lbs. on a 265-65-18.
Commercial tires can be anything from light trucks to bus tires, which can have load limits that far exceed those of passenger or light truck tires.
The tires on your car have a specific speed rating. The speed rating is the maximum speed a tire is certified for, expressed in miles per hour or kilometers per hour.
If you go over the maximum speed rating of your tire, it could cause the tires to overheat and lead to tread separation or blowout, which may result in loss of vehicle control.
The speed rating of your tires is represented by a letter at the end of the tire size code.
For example, a tire size with P225/50R17 91V has a speed rating of V, which is the maximum speed that a tire can support under standard driving conditions (149 mph).
What is the meaning of the W and V speed of tires?
The W stands for speed rating, which is a very important factor in the construction of any tire. The W means that this tire has been tested, and it can be run continuously at 168 miles per hour for 10 minutes.
The V rating is also a speed rating and it means that this tire can be run continuously at 149 miles per hour for 10 minutes.
- W stands for winter. These tires are designed to be used on snow, ice, and other slippery surfaces. They are sometimes called snow tires and have a tread pattern and materials that excel in colder temperatures.
- V stands for speed. This rating is based on the tire’s ability to dissipate heat at speeds greater than 149 mph (240kph). Most V-rated tires are designed to meet the needs of high-performance cars on dry roads, but they still provide good traction in wet conditions.
In many states, the maximum highway speed limit is 75 miles per hour, so why does it matter if a tire can be run at 150 or 170 miles per hour?
Because tires heat up when they are being used, and the faster you go the more the tires heat up. If your tires are not rated to handle the speeds you are traveling at they will begin to overheat and wear out prematurely.
What does 89H mean on a tire?
89H is a tire rating in the United States. It means the tire has a load index of 89, and an H speed rating.
A load index of 89 indicates that this tire is capable of carrying 1356 pounds at maximum inflation pressure.
The 89 means that this tire has a load index of 89. A load index is a number from 0 to 279 that indicates how much weight the tire can safely carry. Most passenger car and light truck tires are rated for loads between 65 and 110.
The H stands for the speed rating of the tire. The speed rating is a letter indicating the maximum safe speed for the tire when it is inflated to its maximum recommended pressure. For example, if your car has H-rated tires, its top safe speed would be 130 mph (210 km/h).
The tire size is the first three digits in the tire size, known as the width. In this case, it’s 205, which represents the width of the tire in millimeters from sidewall to sidewall. The next two digits are aspect ratios.
This measurement is a percentage representing the height of the sidewall compared with the width. So in this example, 65 means that the height is equal to 65 percent of its 205-millimeter width.
The “H” stands for high performance and refers to the speed rating for ZR-rated tires.
What does 113s mean on tires?
- 113 is the aspect ratio of the sidewall in millimeters
- S is the service description. In this case, it is a Speed Rating of 113 mph (181 km/h)
The 113S is an old designation for a tire with an aspect ratio of 113. This means that the tire’s sidewall height is 113% of its section width. This designation was used for H-rated speed-rated tires.
The H rating allows for speeds up to 130 mph. To confuse things, some old DOT markings also show a “Q” rating which allows for speeds up to 99 mph.
The S rating was not a speed rating but rather indicated that the tire has a softer sidewall so it could provide you with better handling and comfort than if it had a stiffer sidewall.
For example, you might have seen the same tire in 215/70R15 with an S and without an S, whereas the one without an S would have been more expensive because of its stiffer sidewall construction.
A tire with the marking 113S is a Low Aspect Ratio tire. The “S” designation indicates that the tire has a Standard (B) load rating.
The 113mm number refers to the width of the tire from sidewall to sidewall in millimeters. This measurement is taken at the widest point of the tire when it is properly seated on a wheel.
How many times does a 91W tire roll per mile?
A 91W tire will roll 61,000/91 = 669 times to go 1 mile.
The tire circumference is approximately:
2 x 3.14159 x (7.75 + 2.1) = 60.8 inches or 5 feet.
So, the tire rolls 5 feet / 669 revolutions = 7.5 inches per revolution.
A 91W tire will roll 1,800 feet (or 549 meters) on 1 gallon of fuel.
A 91W tire is one of the most common tires found on a car today. The “91” refers to the load rating and the “W” refers to the speed rating.
A 91W tire has a maximum load capacity of 2,205 pounds (1,000 kg) at 51 psi (pounds per square inch) and can be driven at a maximum speed of 168 mph with that load.
It has a tread wear rating of 120 and a traction rating of “A” which means it can safely stop a car in wet conditions.
The 91W tire was created by Goodyear in 1929 as a replacement for the older 91H tire which had become obsolete due to advances in automobile design.
The new tire was designed with wider tread blocks and softer rubber compounds that provided greater traction without sacrificing handling or stability during turns or braking maneuvers.
The invention of the 91W tire was considered revolutionary because it allowed drivers to travel at higher speeds while maintaining control over their cars during turns or braking maneuvers without increasing rolling resistance on straightaways.
Conclusion
Tire size is a very important factor when purchasing new tires. The tire size describes the tire’s width, height, and rim size.
You can find your tire size in your vehicle owner’s manual, on the tire placard located on the driver’s side door or glove box, or on your old tires. Here are some examples of how to read tire sizes.
Frequently Asked Questions
1. What does 92Y mean on a tire?
A 92Y tire is a performance tire. The 92 represents the load rating and Y is the speed rating. This means that this tire will be able to carry 1,356 pounds and handle 186 mph when fully inflated.
The load rating is 92. This can be found on the sidewall of your tire and indicates the maximum weight capacity of the tire when it’s inflated to its maximum PSI.
The speed rating is Y. This indicates the maximum speed that a tire can handle when it’s properly inflated.
2. What does 102s mean on a tire?
102S is a metric tire code, which specifies the tire’s size, construction type, and load index. The first number in the metric tire code stands for the width of the tire.
In this case, 102mm, or approximately 4 inches. The letter “S” after that stands for “service description.” This indicates that it is an all-season radial tire.
3. Can I mix V and W-rated Tyres?
You can mix V and W-rated tires on the same wheel, provided they are of the same size and profile. The speed rating is the maximum speed at which the tire operates without failure.
The reason I asked is that it will be built to handle a W-rated tire, but that doesn’t mean you need one.
You may have a new car that is doing only 30mph on average, but the car manufacturer has decided that the car may need a W-rated tire to handle the power and handling ability of the vehicle.
This means you may be paying for something you don’t need.
4. Can I use V-rated tires instead of W?
Yes, you can do that. The V-rated tires have a maximum speed rating of 149 mph (240 kph), whereas the W-rated tires have a maximum speed rating of 168 mph (270 kph).
Even though both of these speed ratings seem ridiculous for a Subaru Outback or any other non-sports car, the higher speed rating on the W-rated tires means they are built with stronger sidewalls and stiffer construction.
This can result in a harsher ride and less comfort, especially when compared to the V-rated tires.
