Aspect ratio tire definition

How to Read & Determine Tire Size for Your Vehicle

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How To Determine Tire Size

Once you have determined it’s time to buy tires, you’ll need to know what size tires are correct for your vehicle. Depending on what you drive, you may be interested in how to find the right tire for your…  

  • Sedans or CUV
  • Light Trucks or SUV
  • Motorcycle
  • RV

This information is usually inside your car’s doorjamb, in your owner’s manual. To ensure your current tire or a replacement tire you may be looking at matches your vehicle’s requirements, it will be good for you to understand how tire sizing works. You may have never paid attention to the string of numbers and letters on every tire, but it’s a gold mine of information.

If you’re unsure of how to read tire measurements from your tire walls, the information and graphics below will tell you how to read tire size, understand and interpret it. If you decide you want to substitute a new size or tire type, consult an authorized tire retailer who can expertly advise you, because many optional tire sizes may have different load capacities and could require wheels of a different rim width or diameter and different inflation pressure.

Not sure you need new tires? Our Tire Replacement Guidance article will help you determine whether it’s time to retire your tires.

Metric Sizing

Most passenger cars, SUVs and light pickups (1/2 ton and smaller) will come with tires that are either P-Metric or Euro-Metric. For P-Metric tires, you’ll see the letter “P” before the number sequence begins: P225/70R16 97H. P-metric is a designation standardized by the Tire and Rim Association for a “passenger car” tire type. For Euro-Metric there will be no preceding letter before the number sequence begins: 225/70R16 98H. Euro-Metric is a designation standardized by the European Tyre and Rim Technical Organization for a “passenger car” tire type.  Both P-Metric and Euro-Metric size tires are designed to primarily be used on passenger vehicles, which can include cars, minivans, SUVs, and other light duty pickup trucks.

If your vehicle is an SUV, Pickup truck or van, you might see a different type of size designation on your placard that is specific for heavy duty light trucks and vans, especially common on ¾ ton and larger pickup trucks and vans. There are two common size types in this category, LT-Metric and Euro-Metric Commercial (aka C-type). Both size types are metric and so use the same structure as P-Metric and Euro-Metric but have some different characters in the size that differentiate them from their passenger car cousins. LT-Metric tires will have the letters “LT” before the size number sequence: LT245/75R17 119/116R Load Range E. Notice that there are two load index numbers and a Load Range, see the section on Load Index for more info.  LT-Metric is a designation standardized by the Tire and Rim Association for a “light truck” type tire. Euro-Metric Commercial or C-Type tires will look very similar to a passenger Euro-Metric size except that there will be a “C” right after the rim size: 23/65R16C 121/119R. Notice that the C-type tires also have two load index numbers. Euro-Metric Commercial, or C-Type is a designation standardized by the European Tyre and Rim Technical Organization for a light truck type tire. Light truck tires are designed to be used on vehicles capable of carrying heavy cargo and are usually only specified by a vehicle manufacturer on vehicles exceeding a certain load capacity.

Other types of tires that fall into the Metric sizing type are Temporary Spares, they start with “T”. If you see a size that starts with “ST,” that means “special trailer” and is only for use on a trailer.

Regardless of whether you are looking at a P-Metric, Euro-Metric, LT-Metric, Euro-Metric Commercial, T or ST tire the numbers in the size mean the same thing.


The first number to appear in your tire size information is the width, in millimeters, of the correct tires for your vehicle: P225/70R16 91S.

Tire width always refers to the measurement from one sidewall to another. Thus, a tire with the measurement “P225” is for a passenger vehicle and has a nominal width of 225 millimeters.

Aspect Ratio

After the slash mark, the next number you see is for the tire’s aspect ratio, which essentially tells you how tall your tire’s profile is: P225/70R16 91S. Aspect ratios are delivered in percentages. Tire makers calculate the aspect ratio by dividing a tire’s height off the rim by its width. If a tire has an aspect ratio of 70, it means the tire’s height is 70% of its width.

Lower aspect ratio tires, such as a 60 series, generally offer vehicle handling performance advantages over higher aspect ratio tires, such as a 75 series, but a typical trade off can be ride harshness.


After the aspect ratio comes a letter that indicates the type of internal construction maintaining your tire’s stability: P225/70R16 91S.

There are two types of construction that you may see on the sidewall of a tire:

  • R – Radial
  • D or “B” or “-“ – Diagonal or Bias Ply

Radial tires are the most common tires on the road in the United States today; thus “R” will usually be shown in the tire size designation. Radial construction means the tire’s internal ply cords are oriented in a radial direction, from one bead over to the other, essentially perpendicular to the direction of rotation. You may also occasionally see RF indicating a run flat tire or ZR indicating a tire that is a speed rating higher than V.

Rim Diameter

The next number is the diameter code, in inches, of the rim onto which the tire can be mounted. For example, a tire with the P225/70R16 91S would fit a rim with a 16-inch diameter.

Load Index

Load index can be a confusing subject because there are so many different caveats, but we will try to explain everything here.

The next figure after the rim size in the sequence is your tire’s load index, which tells us how much weight, in pounds, the tire can support when fully inflated: P225/70R16 91S

We call it the load “index” because the number doesn’t tell us the precise number of pounds the tire can carry, at least not by itself. However, the number does correspond to a specific load capacity listed in an index. Beginning with 1 and ending with 150, numbers in the load index represent carrying capacities of 99 to 7385 lbs.

There are two types of load types for passenger tires though, Standard Load and Extra Load. If a tire is Standard Load there will be no markings indicating it but if it is Extra Load the letters XL will appear after the size and load index.

Standard Load Euro-Metric: 215/55R17 94V

Extra Load Euro-Metric: 215/55R17 98V XL

Passenger car tires like P-Metric and Euro-Metric will only have one load index number where LT-Metric and Euro-Metric Commercial (C-Type) will have two numbers separated by a slash. The first number is the load index if the tire is used in a single application, the second number is the load index if the tire is used in a dual application. Passenger type tires cannot be used in a dual application. Light truck tires will also have a Load Range that is indicated by a letter, such as Load Range E. Load Range is an older term that is still commonly used in the industry so you may hear your tire dealer reference it but the load index numbers are the best way to ensure you have the proper tire.

One important but often misunderstood facet about load index is that the load index numbers between standards organizations (P-Metric vs Euro-Metric) are not necessarily on the same scale. Meaning that two tires in the two different systems that have the same load index number could have different maximum load capacities. This is why it’s important to not only look at the load index number but also verify the actual load capacity.

Speed Rating

The final figure in a tire size sequence is the speed rating, which is indicated by a letter: P225/70R16 91S. Just as your load index number corresponds to a specific load, your speed rating letter corresponds to a particular speed capability based on a standardized laboratory test.

For example, a tire with speed rating “S” is rated for up to 112 mph, while a tire rated “R” is up to 106 mph. Remember that this isn’t a recommended cruising speed. Of course, you should always follow legal speed limits on roadways.

Replacement tires must have the same or higher speed rating as the vehicle’s Original Equipment to maintain vehicle speed capability. If a vehicle has tires with different speed ratings, it is the speed rating of the “slowest” tire that dictates the vehicle top speed.

Flotation Sizing

There is one last sizing type that you should know about, especially if you are in the market for off road tires for a light truck or SUV. It’s called a Flotation size and the numbers in this sizing format are very different from the Metric formats. Flotation sized tires are similar to LT-Metric tires in application except for a few important points. Number one, they cannot be used in dual applications and number two, an equivalent size tire may have different load capacity than its LT-Metric counterpart.

Overall Diameter

The first number in the Flotation tire size is the overall diameter in inches. Pretty straight forward.

Section Width

The second number is the section width (sidewall to sidewall) measurement in inches. Again, fairly simple.


After the section width comes a letter that indicates the type of internal construction: 33X12.50R17LT 120Q.

This is the same as is found in the metric sizing systems.

There are two types of construction that you may see on the sidewall of a tire:

  • R – Radial
  • D or “B” or “-“ – Diagonal or Bias Ply

Radial tires are the most common tires on the road in the United States today; thus “R” will usually be shown in the tire size designation. Radial construction means the tire’s internal ply cords are oriented in a radial direction, from one bead over to the other, essentially perpendicular to the direction of rotation.

Rim Diameter

The next number is the diameter code, in inches, of the rim onto which the tire can be mounted. For example, a tire with the 33X12.50R17LT 120Q would fit a rim with a 17-inch diameter.

LT type

The letters LT will be after the Rim Diameter indicating that this tire type is intended for Light Truck vehicles similar to the LT-Metric and Euro-Metric Commercial (C-Type) tires.

Load Index and Speed Rating

Load Index and Speed Rating have the same meaning and format as the tires using the metric sizing system. Note that since flotation tires cannot be used in a dual application there will be only one load index number instead of two.  

Uniform Tire Quality Grading

Another group of stamping on certain types of tires is the Uniform Tire Quality Grading or UTQG. This grading and stamping is required for passenger car tires (i.e. P-metric and Euro-metric) in the all season and summer categories. Dedicated winter tires, Light Truck (LT-Metric, Euro-Metric Commercial, Flotation) and Motorcycle tires are excluded from this requirement.

Quality grading is designed to make the tire purchase decision easier for you. Ideally, the system is intended to provide simple, comparative data so you can make an intelligent buying decision. However, the ratings are based upon test results achieved under special conditions. This means it’s possible to misinterpret the comparative data as it relates to your individual driving habits, conditions, etc. You should still rely on your service or tire professional for assistance. 

Quality grading designates the comparative performance levels of a tire based on government-specified tests but commissioned by the individual tire manufacturers. All tire manufacturers are required to grade regular and all-season passenger tires in three categories:


  1. Treadwear
  2. Traction 
  3. Temperature

The treadwear grade is a comparative rating based on the wear rate of the tire when tested under controlled conditions on a specified government test course for 6,000 miles (9,600 km). For example, a tire graded 150 would wear one and a half times as well on the government course as a tire graded 100. However actual tire performance depends on driving habits, road characteristics, service practices, and other factors that can influence the outcome. 

Traction Grades AA, A, B and C 
The traction grades from highest to lowest are AA (the highest), A, B and C. They represent how well tires stop on wet pavement as measured under controlled conditions on specified government test surfaces of asphalt and concrete. C-rated tires will have the lowest traction performance.  


Temperature Grades A, B and C 
The temperature grades A, B, and C represent the tire's resistance to the generation of heat and its ability to dissipate heat when tested under controlled conditions on a specified indoor laboratory test wheel. Sustained high temperature can cause the tire’s material to degenerate and reduce tire life, and excessive temperature can lead to sudden tire failure. The grade C corresponds to a performance level all passenger car tires must meet under the Federal Motor Vehicle Safety Standard No. 109. Grades A and B represent higher levels of performance on the laboratory test wheel than the minimum required by law. 


DOT Quality Grades 
All passenger car tires must conform to other federal requirements in addition to these grades.

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Tire Aspect Ratio: What is it


When you start looking at new tires, you realize that there are many different factors and sizes to keep in mind. And we mean a lot:

  • How wide is the tire?

  • How tall is the tire? 

  • How fast can the tire go? 

  • How much weight can the tire hold? 

  • How much wood could a wood-tire chuck…

Wait, that last one is for something else. But you get our point. Many variables differ from tire to tire, and it’s important to know what they are and how they affect your ride. 

Luckily, every tire on the market has this information stamped on its rubber sidewall. It’s pretty easy to spot and read—if you know what you’re looking for. 

Today, we will talk about tire aspect ratio, where to find it on your tire, and what it means.

What Is a Tire Aspect Ratio?

Tire aspect Ratio is the percentage ratio of the tire’s sidewall height compared to its rubber width. 

Don’t worry; we’ll break it down for you. Tire Aspect Ratio is a percentage that reflects how much of a tire you see outside of the rim flange compared to its actual width. 

The Aspect Ratio is pretty important and can determine how a tire looks and performs. As we mentioned, it’s conveniently available on the side of any tire. 

Where Do You Find the Tire Aspect Ratio?

The Aspect Ratio is stamped onto the exposed sidewall of any tire alongside a bunch of numbers and letters that tell you everything you need to know about your tire. It looks like this:

265/60R18 110H

This example is the numbers you would find if you just bought a set of reliable Nexen Roadian HP tires online at for only $62 a month. 

Granted, if you bought them through Rent A Wheel, you could have our professional tire technicians install them on your vehicle for free. Not to mention, with our state-of-the-art visualizer and our happy-to-help service, you always know your new tires will fit.

Still, you’re reading this because you want to know everything about your tires, which is fantastic. So, let’s carry on. 

This string of numbers and letters might look confusing, but we’ll explain each piece step-by-step. From right to left, here’s how to read this handy little number. 


The first number we see is “265.” This is the width of the tire from sidewall to sidewall in millimeters. It’s important to note that some of these numbers are in inches and some in millimeters, so keep an eye out! This is the first important number we’re looking for when shopping for rims. It’s also one of the important elements of finding the aspect ratio.

Aspect Ratio

As we’ve mentioned, the aspect ratio is the sidewall height compared to its width. In this case, the tire height is 60% of its width. 

Some quick math tells us that 60% of 265 millimeters is 159 millimeters. That’s the height of this tire’s sidewall. 

So, that’s the aspect ratio. Because we know our readers are eager to learn everything they can, we’ll explain the rest of these numbers and letters for you, too. 


This is the same on most tires you’ll encounter. The “R” means that the interior construction of the tire is radial. 


This might sound familiar from geometry class. Diameter is the measurement of the hole in the tire from one inner sidewall to the other. 

Don’t get this confused with the height of the tire, which would be the diameter from where it touches the ground to its tallest point. This is the size we look for when fitting rims. 

The diameter of our Nexens is 18 inches. Yes, we switched back to American measurements for this one. 

Load Index

The load index is at the end of this sequence. Well, almost the end. The load index number dictates the amount of weight this tire is rated to carry. In this case, the Nexen tires have a Load Index Number of 110, meaning they can support 2,337 pounds per tire. Multiply that by four, and you’ve got a set of wheels that can hold 9,348 pounds in total. Not too bad!

Speed Index

Finally, we get to the last letter! This is the speed rating identifier. This letter relates to the Tire Speed Rating Chart. Each letter on the chart tells you the tire’s maximum speed. So, our shiny new Nexen Roadian HP tires have a Speed Rating number of H. This chart tells us we can safely go 130 miles per hour. According to the tires, not speed laws, which Rent A Wheel always obeys and expects smart drivers to do the same!

What Does It Mean?

So, what does your tire's aspect ratio mean for you? And why is it important when shopping for a new set?

Well, the higher the aspect ratio, the more sidewall you will see from your tire’s side profile. This has aesthetic implications, and some people have a particular vision for their vehicle’s look. 

If you want a low-profile performance tire that almost blends with your sweet rims, keep an eye out for a lower aspect ratio. 

If you’re looking to set up your Jeep or truck with a set of tires that you can take off-roading, a higher aspect ratio will help out because of its sidewall height. That extra rubber on the tire sides is going to add traction when you’re in the mud. 


All in all, the tire aspect ratio is just one piece of information to keep in mind when shopping for new tires. What you’re planning on doing with your vehicle, where you drive, and what you want everything to look like is all affected by one number.

It’s also important to remember all the other bits of information we’ve covered. You can’t look at just one component when shopping for new tires. You have to pay attention to make sure you’re getting exactly what you need and want.  

At Rent A Wheel, we have a team of professional tire experts ready to chat with you online about what tires will suit your needs best. We’ll get you fitted with the perfect tires and wheels for your vehicle. 

Still a little confused on how the tires are going to look on your sick ride? Don’t worry; our state-of-the-art visualizer is here to help. Just input your car’s make, model, and color, and we’ll show you exactly how those brand-new tires and rims are going to look on the road. 

If you’re thinking, “Gee-whiz, I wish I could buy new tires today, but the ones I want are just too expensive,” have no fear—Rent A Wheel is here. 

Our flexible payment plan options mean that you can make low monthly payments on your tires over time instead of dropping a big wad of cash all at once.

We want to make sure every driver who chooses Rent A Wheel drives away with exactly what they want and need at a reasonable price. Did we mention that we’ll even install your newly purchased tires for free? That’s a pretty solid deal. 


How to Read Tire Size and Sidewall Markings | Live About

Tire Load Index Chart | Tyre Size Calculator

Tire Speed Rating Chart | Tyre Size Calculator

Tire marking. How to correctly determine tire parameters

Do you want to choose a tire for your car, but do not understand tire markings well? It's not a problem! In this section, we will help you figure out what tire parameters are, what they mean, and which tire is right for your car.

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Explanation of tire markings.

195/65 R15 91 TXL

195 is the tire width in mm.

65 - Proportionality, i.e. profile height to width ratio. In our case, it is equal to 65%. Simply put, with the same width, the larger this indicator, the higher the tire will be and vice versa. Usually this value is simply called “profile”.

Since the tire profile is a relative value, it is important to take into account when choosing rubber that if you want to put tires with a size of 205/65 R15 instead of the size 195/65 R15, then not only the width of the tire will increase, but also the height! Which in most cases is unacceptable! (except when both of these sizes are indicated in the car's operating book). You can calculate the exact data on changing the outer dimensions of the wheel in a special tire calculator.

If this ratio is not specified (for example, 185/R14C), then it is equal to 80-82% and the tire is called full profile. Reinforced tires with this marking are usually used on minibuses and light trucks, where a large maximum wheel load is very important.

R - means a tire with a radial cord (in fact, almost all tires are made this way now).

Many mistakenly believe that R- means the radius of the tire, but this is precisely the radial design of the tire. There is also a diagonal design (indicated by the letter D), but recently it has practically not been produced, since its performance is noticeably worse.

15 - wheel (rim) diameter in inches. (It is the diameter, not the radius! This is also a common mistake). This is the “landing” diameter of the tire on the disk, i.e. is the inside size of the tire or the outside of the rim.

91 - load index. This is the level of maximum permissible load on one wheel. For passenger cars, it is usually done with a margin and is not a decisive factor when choosing tires (in our case, IN - 91 - 670 kg.). For minibuses and small trucks, this parameter is very important and must be observed.

Tire load index table:

T - tire speed index. The larger it is, the faster you can ride on this tire (in our case, IS - H - up to 210 km / h). Speaking about the tire speed index, I would like to note that with this parameter, the tire manufacturer guarantees the normal operation of the rubber when the car is constantly moving at the specified speed for several hours.

Speed ​​index table:

American Tire Marking:

There are two different markings for American tires. The first one is very similar to the European one, only the letters “P” (Passanger - for a passenger car) or “LT” (Light Truck - light truck) are placed before the size. For example: P 195/60 R 14 or LT 235/75 R15. And another tire marking, which is fundamentally different from the European one.

Example: 31x10.5 R15 (corresponding to European size 265/75 R15)

31 is the outside diameter of the tire in inches.
10.5 is tire width in inches.
R - a tire with a radial design (older tire models were with a diagonal design).
15 is the inner diameter of the tire in inches.

Generally speaking, except for inches that are unusual for us, the American tire marking is logical and more understandable, unlike the European one, where the height of the tire profile is not constant and depends on the width of the tire. And here everything is simple with decoding: the first digit of the standard size is the outer diameter, the second is the width, the third is the inner diameter.

Additional information indicated in the marking on the sidewall of the tire:

XL or Extra Load is a reinforced tire, the load index of which is 3 units higher than that of conventional tires of the same size. In other words, if a given tire has a load index of 91 marked XL or Extra Load, then this means that with this index, the tire is able to withstand a maximum load of 670 kg instead of 615 kg (see the table of tire load indices).

M+S or M&S tire marking (Mud + Snow) - mud plus snow and means that the tires are all-season or winter. Many summer tires for SUVs are labeled M&S. However, these tires must not be used in winter, as winter tires have a completely different rubber compound and tread pattern, and the M&S badge indicates good flotation performance.

All Season or AS all season tires. Aw (Any Weather) - Any weather.

Pictogram * (snowflake) — rubber is designed for use in harsh winter conditions. If this marking is not on the sidewall of the tire, then this tire is intended for use only in summer conditions.

Aquatred, Aquacontact, Rain, Water, Aqua or pictogram (umbrella) - special rain tires.

Outside and Inside ; asymmetric tires, i.e. It is important not to confuse which side is the outside and which is the inside. When installing, the Outside inscription must be on the outside of the car, and Inside on the inside.

RSC (RunFlat System Component) - RunFlat tires are tires on which you can continue to drive a car at a speed of no more than 80 km / h with a FULL drop in pressure in the tire (due to a puncture or cut). On these tires, depending on the manufacturer's recommendations, you can drive from 50 to 150 km. Different tire manufacturers use different designations for RSC technology. For example: Bridgestone RFT, Continental SSR, Goodyear RunOnFlat, Nokian Run Flat, Michelin ZP etc.

Rotation or arrow This marking on the tire sidewall indicates a directional tire. When installing the tire, you must strictly observe the direction of rotation of the wheel, indicated by the arrow.

Tubeless - tubeless tire. In the absence of this inscription, the tire can only be used with a camera. Tube Type - indicates that this tire must be used only with a tube.

Max Pressure ; maximum allowable tire pressure. Max Load - the maximum allowable load on each wheel of the car, in kg.

Reinforced or the letters RF in the size (for example 195/70 R15RF) means that this is a reinforced tire (6 layers). The letter C at the end of the size (for example 195/70 R15C) indicates a truck tire (8 layers).

Radial this marking on the rubber in the standard size means that this is a radial construction tire. Steel means that there is a metal cord in the tire structure.

Letter E (in a circle) - the tire meets the European requirements of ECE (Economic Commission for Europe). DOT (Department of Transportation - US Department of Transportation) is an American quality standard.

Temperature A, B, or C Temperature resistance of the tire at high speeds on the test bench (A is best).

Traction A, B, or C Tire wet braking capability.

Treadwear ; relative expected mileage compared to a specific US standard test.

TWI (Tread Wear Indiration) - tire tread wear indicators. The marking on the TWI wheel can also be with an arrow. Pointers are located evenly in eight or six places around the entire circumference of the tire and show the minimum allowable tread depth. The wear indicator is made in the form of a protrusion with a height of 1.6 mm (the minimum tread value for light vehicles) and is located in the tread recess (usually in the drainage grooves).

DOT - Manufacturer's coded address, tire size code, certificate, issue date (week/year).

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Tire marking: tire speed and load index


  • Introduction
  • Speed ​​index
  • Load index
  • Tire marking example
  • Tire marking with colored labels

The selection of tires is carried out taking into account a number of parameters - their diameter, width, and profile height must be taken into account; in addition, the speed index and the load index are of no small importance. The manufacturer always indicates these indicators on the sidewall. What they mean will be discussed below.

The value corresponds to the maximum permissible speed at which tires of this type can be operated. Accordingly, if a motorist plans to drive at a higher speed, it makes sense to think about buying tires with a higher index value.

Speed ​​index table

Index K L M N P Q R S T U H V VR W Y ZR
Max. speed, km/h 110 120 130 140 150 160 170 180 190 200 210 240 >210 270 300 >240

For example, if the tire has a mark that the speed index corresponds to the letter V, then this indicates that it is strongly not recommended to drive on these tires at a speed of more than 240 km / h.

This is a no less significant parameter, which, in contrast to the value discussed above, is indicated by a number. In the tire label, the load index factor follows the tire diameter.
For example, a value of 91 indicates that the maximum allowable load per tire cannot exceed 615 kg. Accordingly, the total load calculated on 4 wheels should not exceed 2460 kg. The full table of load indices contains coefficient values ​​from 1 to 279. For passenger tires with a diameter of 13 inches, the load index can be, for example, 75. And for wheels with a diameter of R20, this coefficient will reach 120.

Load index table

Of course, the given load value does not mean that if it is exceeded, the tire will immediately be torn to pieces. A short-term excess of 20-30% is acceptable, but this should not become a habit.

According to EU regulations (ECE-R54), all tires that are planned to be used for commercial vehicles must be marked with a "Service Description" (translated as "Operating Conditions"). It is a special code next to the tire size, which carries information about the load index calculated for single and dual wheels (as an option - 102/100R).

The information must be recorded on both sidewalls of the tire. The 1st digit indicates the load capacity of the tire in the case of a single installation - the 2nd corresponds to the level of the maximum load on one tire with twin wheels. Additional markings are used to indicate the corresponding tire loads at higher speeds. Additional markings are always circled.

205/55 R16 94H XL

205 - the width of the tire profile, indicated in mm. In this case - 205 mm .
55 - the value of the height of the tire profile in%, determined from its width. In the situation under consideration - 55% of 205 mm will be equal to = 112.75 mm.

Given that the tire profile is a relative value, the following point must be taken into account when choosing rubber: if instead of the size 205/55 R16 you want to install tires with the size 215/55 R16 , then not only the width of the tire will increase, but also her height! Such a situation is in most cases unacceptable (the only exception is the situation in which both sizes are given in the car's operating book). If this ratio is not given (as an option - 185 / R14C ), this means that its value is 80-82%, and the tire is considered full profile. Reinforced tires with this marking are most often used on minibuses and light trucks - in these vehicles, the maximum allowable wheel load is of great importance.

R - characterizes the design of the tire. In the situation under consideration, the tire is radial - the design determines the location of the carcass cord threads.
Consider designation R indicates the tire radius is completely wrong. The symbol refers solely to its radial design. There is also a diagonal design (it corresponds to the letter D ), but today almost no one produces it. Reason: poor performance.

16 - the value of the diameter of the wheel (disk), indicated in inches. This diameter for the tire is internal, for the disk it is external. That is why it is called "landing".

94 - load index (it was already mentioned above). The interpretation of the most commonly used coefficients is given in the table of load indices. Often, the load is decoded on the tire itself: two numbers follow the Max Load inscription - the first in kg, the second in pounds.

H - tire speed index. Please note that with this parameter, the tire manufacturer guarantees the normal operation of the rubber when the vehicle is driven non-stop at the specified speed for several hours. The decoding is given in the speed index table.

XL - this characteristic indicates that the tire is reinforced. Its load index is 3 units higher than conventional tires of the same size.

Separately, it is necessary to mention the RunFlat technology, which provides for the strengthening of the sides of the tire. As a result of damage, such a tire does not deflate and sag under the weight of the car, but allows you to drive a certain distance at a certain speed even after a complete loss of pressure. Those. The wheels are provided with additional protection. This quality is marked on tires in different ways - RSC, MOE, AOE - depending on the brand of car.

In addition to the above symbols in the form of letters and numbers, important information is indicated on the tires through colored labels. Below is an interpretation of each of them.

The marking is yellow (may be in the form of a circle or a triangle).

Apply in the lightest part of the tire. When installing a new tire on a rim, the yellow mark should be aligned with the heaviest part of the rim (easy to identify - it always corresponds to the nipple attachment point).

The label makes it possible to optimize wheel balance and use lighter weights. On used tires, the yellow marking is no longer relevant - tire wear leads to a shift in its balance.

Red marking

It has the appearance of a red dot on the tire and indicates the location of the maximum deviation of the radial force. At this point, the tire has the largest radius due to the greater number of layers and it is the most rigid. Inhomogeneity of tire plies is normal during tire manufacture.

The red dot on the tires during installation must match the white dot on the rims (note that both marks are placed on the original car tires). The white dots on the rims indicate the location closest to the center of the wheel. Alignment of the red dot on the tires and the white dot on the rims is recommended to reduce the effect of maximum heterogeneity in the tire. So it is possible to provide a better balance of the power characteristics of the wheel. In conventional tire fitting, one should not attach great importance to the red mark - it is better to focus on the yellow mark, combining it with the nipple.

Number in white stamp

Corresponds to the individual number of the inspector conducting the final inspection of the tire at the manufacturing plant. The stamp can also be of other colors, this does not change the meaning of the label.

Colored stripes

These designations are applied to the tire tread for easy identification of the tire in stock. For tires of all models and different sizes, this marking is different. There is no single unification of the application of colored stripes. Details on the marking of certain colors on tires are prescribed in the manufacturer's specifications, and can also be indicated on its official website.

Colored stripes make it easy to identify the size and model of a single stack of tires stacked in a warehouse. The semantic load of color bars on the bus is unambiguous.

Additional data that can be identified from the marking on the side of the tire

  • The letter C in the tire marking means that the tires are “reinforced” (added up to 8 reinforcing layers), with a large load factor.

  • The letter E, circled - compliance with European standards.

  • DA (stamped) - Minor manufacturing defects, which do not interfere with normal operation.

  • DOT - compliance with US quality standards.

  • M + S (mud and snow) - the designation indicates that the tires are all-weather. The designation AS and All seasons are interpreted in the same way.
    The snowflake design indicates that the rubber can be used in the most severe winter conditions. In its absence, the tire can only be used in the warm season and in the absence of a large amount of precipitation.

  • Made in Finland - country of origin.

  • MaxLoad - the maximum permissible load based on each wheel of the machine, in kg.

  • Max Pressure - the maximum allowable pressure level in the tire, in kPa.

  • Outside or Side Facing Out and Inside or Side Facing Inwards - indicates tire asymmetry. It is necessary to install with the Outside inscription outward, and the Inside inscription - inward.

  • PLIES: TREAD - compound of the tread layer.
  • RF (Reinforced) - designates a reinforced structure (up to 6 reinforcing layers.
  • RSC tires are tires that allow you to continue driving a car at a speed not exceeding 70 km / h with an absolute decrease in pressure in the tire that occurs due to a puncture or cut). The distance that can be driven is determined by the manufacturer - the value varies from 50 to 150 km.
  • Rotation - indicates that the tire is directional. When installing a tire, it is necessary to strictly observe (along the arrow) the direction of rotational movements created by the wheel. With asymmetric tires: LEFT - the tire is installed on the left side of the car. RIGHT - the tire is installed on the right side of the car.

  • Sidewall - composition of the sidewall layer

  • Tubeless - tubeless tire. If this inscription is not present, then it is possible to use a tire only with a camera.

  • TubeType - indicates the possibility of operation with a camera only.

  • Steel - indicates the presence of a metal cord in the tire.

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