This is one of the simplest types of tuning. Why is this needed? There are many options. The most common reason is dislike appearance... Let's say you want the wheels to look better. For this, the disc must be of a larger diameter. Or bought a used car, and the design rims it absolutely does not suit you. Perhaps you liked some specific wheels, but their dimension is not included in the list recommended by the car manufacturer. You can also change the wheels for reasons of practicality. But how can the installation of such wheels turn out in the future? Let's figure it out.

First, let's remember the key parameters of the wheel.

• 185 - tire profile width in mm
• 65 - the percentage of the height of the tire cross-section to the width
• R - designation of a tire of a radial structure
• 15 - landing diameter in inches

So, there are several ways to move away from the stock wheel size.

1. Wider tire

When saving regular size increase the width of the tire profile while maintaining the percentage of height to width. In our example, we get 195/65 R15. It is important to know that all vehicles are designed to be fitted with snow chains of at least 12 mm in size. Indeed, in some European countries, driving on mountain roads without chains is prohibited, and no self-respecting manufacturer will make a car so that it cannot be used in the mountains of France or Switzerland. Therefore, an increase in the width of the tire profile is permissible in most cases by up to 24 mm. This will make the car slightly softer on the move, and wider tires will improve braking performance.

2. Higher tire profile

Leave it the same, and increase the percentage of the tire's profile height to width to 70. In our example, we get 185/70 R15. The outer diameter of the wheel increases by 20 mm, which is quite acceptable (remember in reserve for installing chains). Everything would be fine, but in our specific example the factor intervenes is that tires of this dimension are produced mainly for commercial vehicles and they are too tough and expensive to fit in a car. However, in other dimensions, the situation may be different.

3. Change the diameter of the disc

The story with the car of one friend is very indicative. He bought a Kia Rio with a 1.6 engine and a 6-speed automatic. The standard wheels of the car were 185/65 R15 in size. The owner was driving through the summer season and was not happy with the car's stiff suspension and insufficient ground clearance. Then he decided to change the behavior of the car, not by tuning the springs with shock absorbers, but by working with the wheels. In preparation for the next summer season, he used forged wheels with a diameter of 14 inches, completely matching the installation dimensions.

There is more air between the wheel and the tire. The outer diameter of the wheel has also grown (by 9 mm). As a result, the ride is fantastic. When overcoming irregularities in the road, the car, initially not famous for its energy-intensive suspension, began to resemble supercomfortable russian roadsah cars of the Logan family. Softly, quietly, smoothly. All the problems of the killed Russian roads and the rigid Korean suspension disappeared. He does not plan to drive, because the possible deterioration of directional stability at very high speeds does not bother him.

However, a decrease in disc diameter is very rare. Much more often it happens that the owner chooses disks one or even two sizes larger. And "wraps" them in low profile tires... At the same time, the overall dimensions of the wheel hardly change or grow within the permissible limits.

It looks impressive, but first of all the smoothness of the ride suffers. And the chances of damaging a wheel on a bad road are much greater, because the lower the profile height of the tire, the less the ability of such a tire to withstand shock loads. In everything you need to know when to stop. Returning to our example, Rio and Solaris cars in expensive trim levels sport 16-inch wheels with 195/55 R16 tires. In this case, you can play a little with the sizes. For example, a 195/60 R16 tire will fit into the wheel well without any problems, since its outer diameter will increase by only 19 mm. Clearance will grow by a decent 9.5 mm, but about the softness of the stroke provided by 15-inch wheels basic modification, you can forget.

4. Increase the width of the disk and change the offset

A separate story when the car owner decides to install wider discs. Some people like it when the wheel protrudes slightly beyond the arch. Note that changing the dimensions of the rim and tire can significantly increase the weight of the wheel assembly. Such weighting will negatively affect the resource of the suspension elements and even the bodywork, since large unsprung masses can cause resonant vibrations for which the suspension is not structurally designed. It is also important to remember about such a parameter as wheel offset.

Those who like to change the offset of the rims, as a rule, tend to place the wheels wider. The aesthetic component of such changes is controversial, but the resource of the suspension elements will certainly decrease.

The consequences of increasing the overall dimensions of the wheel:

pros	Minuses
Increase in clearance... Every millimeter on our roads ground clearance on the account. If the car bottom is 5–10 mm farther from the potholes, then there is less chance of damaging it on a bad road.	The wheel can touch the body elements.If the width and diameter of the wheel grows no more than 24 mm from maximum size wheels from the number recommended by the manufacturer, then this problem is not terrible for you. Only after that you can't put on the chains.
Improved efficiency.Economy improves slightly on country roads, especially on vehicles with gearboxes that have few gears (4 or 5).	Increase in car swelling.Yes, the roll will increase slightly, due to the fact that the center of mass is now located slightly higher. In practice, this means a slightly lower limiting transfer speed.
Changing the speedometer and odometer readings.Standard devices always overestimate the readings. You can check by GPS. And with new ones, a little big wheels, the readings will come in line with reality. Whether it is plus or minus, you decide. Still, such a discrepancy is made primarily for security reasons. We are for accurate instrument readings.	Decrease in dynamic performance.The new wheels are a little harder for the engine to turn, and they themselves are a little heavier.
Reducing disc overhang (when the wheels protrude beyond the wheel arches) provides a wider track, which enhances lateral stability cars.	Wide disc is easily damaged when touching the curb. In addition, if the width of the disc is much larger than the standard, the tire casing does not work correctly. It leads to increased tire wear.
In most cases the appearance becomes more aesthetic and catchy.	Strongly protruding wheel arches overload the wheel bearings and make it difficult to drive... As soon as the front wheel hits an uneven road, the steering wheel literally pulls out of your hands.

For calculations it is convenient to use tire calculator.

Legal aspect

By law, non-standard wheels are prohibited. Therefore, any experiments with tire or rim dimensions are illegal. An exception if the new dimension is allowed to be installed by the manufacturer. However, in reality, not everything is so scary: if wheel disks on a small car, you are not boiled up to a width of 12 inches, if the diameter is not 19 inches or more, then such wheels will not arouse the interest of the traffic police. But with the receipt diagnostic card there will already be problems.

What if you put more wheels? - ZR examination

Do you want to choose a tire for your car, but don't know much about tire labeling? It's not a problem! In this section, we will help you figure out: what are the parameters of the tire, what they mean, and what kind of tire is suitable for your car.

Find tires / tire catalog

Decoding of tire marking.

195/65 R15 91 T XL

195 is the width of the tire in mm.

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

Since the tire profile is a relative value, it is important to take into account when selecting tires that if instead of the 195/65 R15 standard size you want to put tires with the size 205/65 R15, then not only the tire width will increase, but also the height! Which is unacceptable in most cases! (except for the cases when both of these standard sizes are indicated in the car manual). Accurate change data external dimensions wheels you can calculate in a special tire calculator.

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

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

Many people mistakenly think that R- stands for the radius of the tire, but this is precisely the radial design of the tire. There is also a diagonal design (denoted by the letter D), but recently it has practically not been produced, since it performance characteristics much worse.

15 - wheel (disk) 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 disc, i.e. this is the inner tire size or outer rim.

91 - load index. This is the maximum permissible load per wheel. For passenger cars it is usually done with a margin and when choosing tires is not a decisive value, (in our case, ID - 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 more speed you can ride on this tire (in our case IS - N - up to 210 km / h). Speaking about the tire speed index, I would like to note that with this parameter the tire manufacturer guarantees normal work rubber with constant movement of the machine at the specified speed for several hours.

Speed \u200b\u200bIndex Table:

American tire markings:

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

For example: 31x10.5 R15 (corresponds to European standard size 265/75 R15)

31 is the outer diameter of the tire in inches.
10.5 - tire width in inches.
R - radial tire (older models of tires were diagonal).
15 is the inner diameter of the tire in inches.

Generally speaking, apart from the unusual inches, the American tire marking is logical and more understandable, unlike the European one, where the tire profile height is not constant and depends on the tire width. And here everything is simple with the 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 - a reinforced tire, the load index of which is 3 units higher than that of conventional tires of the same standard size. In other words, if a load index of 91 is indicated on a given tire, marked XL or Extra Load, it 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 SUV tires are labeled M&S. However, these tires cannot be used in winter timesince winter tires have a completely different rubber composition and tread pattern, and the M&S badge indicates a good cross-country performance of the tire.

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

Pictogram * (snowflake) - rubber is intended for use in harsh winter conditions... If the sidewall of the tire does not have this mark, then this tire is intended for summer use only.

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

Outside and Inside; asymmetrical tires, i.e. it is important not to confuse which side is external and which is internal. When installed, the Outside lettering should 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 driving a car at a speed of no more than 80 km / h with a FULL pressure drop in the tire (in case of a puncture or cut). On these tires, depending on the manufacturer's recommendations, you can drive from 50 to 150 km. Different manufacturers Tires use different designations of RSC technology. For example: Bridgestone RFT, Continental SSR, Goodyear RunOnFlat, Nokian Run Flat, Michelin ZP, etc.

Rotation or an arrow on the sidewall of the tire indicates a directional tire. When installing the tire, the direction of rotation of the wheel indicated by the arrow must be strictly observed.

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

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

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

Radial This marking on a rubber in a standard size means that it is a tire of a radial design. Steel means there is a metal cord in the tire construction.

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

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

Traction A, B or C - the ability of the tire to brake on a wet road surface.

Treadwear; the relative expected kilometers traveled versus the US specific standard test.

TWI (Tread Wear Indiration) - indicators of tire tread wear indicators. The TWI wheel can also be marked with an arrow. The gauges are evenly spaced at eight or six places around the tire circumference and indicate the minimum tread depth allowed. The wear indicator is designed as a protrusion with a height of 1.6 mm (the minimum tread size for light vehicles) and is located in the groove of the tread (usually in the drainage grooves).

DOT - Coded manufacturer address, tire size code, certificate, production date (week / year).

To simplify the determination of the tire size, a special tire calculator has been developed that allows the user to dispense with the need to decipher the numerical values \u200b\u200bon the side surfaces of the rubber. With the help of such a calculator, the difference in tire sizes, profile height and other parameters is determined. In addition, such a calculator allows you to receive other related information, for example, on deviations in the speedometer, changes in ground clearance, and so on.

Purpose of the Visual Bus Calculator

The visual calculator allows every car owner to easily determine the dimension of the tires and the width of the required rims. With its help, it is possible to determine the diameter of the wheels, the error of the speedometers, the increase in the road track and changes in the clearance under the bottom of the car. Using a tire calculator, it is extremely easy to determine optimal sizesuitable for your specific vehicle model. The built-in size conversion system allows you to instantly convert values \u200b\u200bfrom inch to meter and back.

It is advisable to use the potential of the calculator in cases when the car owner switches to using tires and wheels that are different from the original size. It allows you to visually determine the main dimensions, and then simulate them for the selected vehicle. In turn, the selection of tires with its help is impossible, since initially it does not provide for division by manufacturer.

Selection and comparison of tires according to the calculator 2.0

In case of installing new wheels and tires of a different size, based on the data received from the calculator, it is advisable to additionally carry out a number of measurements. Determine the appropriate distance along inside between the wheel and the suspension; and from the tread to the shock absorber cup. In addition, you will need to measure the distance between the tread, fender and steering rods.

In turn, when choosing new tires, it is necessary to proceed from the advisability of a slight deviation in geometrical dimensions new tires from previously used ones. The significant size of the dimensions will cause instability in the movement of the car.

Each car is initially created for certain parameters and dimensions. This fully applies to the permissible size of the used disks and rubber. Accordingly, the selected rubber models must be within the established limits. The use of a tire calculator allows you to simplify the selection process as much as possible, depending on a specific vehicle.

Russians have to regularly face the replacement of rubber, primarily seasonal. The simplest solution in this situation is to use rubber of the same size. While maintaining the dimension of the rubber, the wheel will also retain its original dimensions.

In cases where rubber of a different size is selected, it is necessary to select the appropriate disks to obtain a wheel with the required dimensions. At the same time, by changing the typical tire sizes, it is possible to control the driving characteristics of the car, giving additional softness or rigidity. The higher the profile used, the softer the car feels on the road. As the profile decreases, the stiffness increases, and the narrower tires provide more grip on snow-covered surfaces, so they look more advantageous on winter roads.

At the same time, when selecting the dimension of tires and wheels, it is required to adhere to the permissible dimensions. For example, tires that are too wide will touch the wheel arches in motion, rubbing them, and wear intensively on their own. It is worth taking into account the fact that changing the size of the wheels affects the operation of the speedometer, in particular the magnitude of the error.

From the outside, it may seem that the variety of available configurations significantly complicates the calculations, but the tire calculator greatly simplifies the selection process using 3D modeling. The correct selection of tires is not only the necessary safety, but also the optimization of the road capabilities of the car. At the same time, the presence of the metric and inch system of sizes allows you to work with both American and European standard sizes without problems.

Car owners use a tire calculator to find the right tire and wheel size. All calculations are performed online. The user does not have to deal with lengthy, incomprehensible calculations. The application is multifunctional, as the motorist will be able to understand how to change the dimensions of the wheel, taking into account the changes in the size of tires and wheels. Let's consider the features of using the service.

Tire calculator functionality

The tire selection calculator will be able to help with the selection of tires suitable for a specific car in terms of size and characteristics. The owners of the transport resort to the services of the service when it is time to replace the tires and disks with the vehicle. In order not to waste time on meaningless "changing shoes", checks, use the proposed online service. Bus calculator features:

• you can calculate the dimensions of tires;
• service provides different parameters - wheel diameters, changes in the clearance between the road and the car (clearance), track widening;
• help in converting inches to millimeters or vice versa, using the American and European size tables.

The tire calculator was designed to speed up the selection of tires, making the procedure many times easier. Since every car owner faced the difficulties of choosing, online calculators quickly gained popularity among users.

How to use a tire calculator

There are some tips to help you use the tire size calculator for its intended purpose. Step-by-step instruction consists of the following stages:

1. In the form you will need to enter the size of the tires installed on the car, as well as those that you would like to install.
2. A special table with the calculation results will appear in front of the user. From these data, it will be possible to find out which tires are needed for a particular transport.
3. After selecting tires, you can proceed to calculating the size of the disks. Here you will need to specify the exact data - the maximum / minimum width of the disk installed on the car. The service will perform all calculations automatically.
4. If you need to convert inches to millimeters, you can use an online converter. This action will allow you to find analogues with American sizes and with European ones. Comparison through the tire calculator will be as accurate as possible, since all the necessary information has been entered into the online service database.

The general selection procedure is very simple, but the owner of the car will definitely need to enter the initial data. The parameters should be as accurate as possible so that there are no errors or inaccuracies in the subsequent results.

You can use this service on our website. The program is freely available, anyone can make calculations in a few minutes. To simplify the process of use, it is worth using the instructions given.

When choosing a new "shoe" for a car, it is important to understand how to match the wheels to the tires. Many parameters of the wheel should be taken into account to avoid dangerous situation on the road due to a bent rim or a popping bolt. The seat is always calculated for a specific brand of car.

Why buy OEM wheels?

Before dealing with the question of how to choose wheels to tires, you should check with the service: will your actions affect the warranty. If you independently select new wheels that differ in design from the standard ones, the manufacturer can remove your car from the warranty, and all repairs will have to be paid out of your own pocket. It is better to inquire about all permitted rim and tire sizes for your brand.

Most dealers have ready-made paired wheel models for sale. They can also tell you how to choose the wheels for the tires, and show you the calculation method. It should be remembered that their prices will be much higher. It is better to tackle this issue on your own and choose what you need exactly.

Wheel width

If, nevertheless, it is decided to change the wheels on your own, then we will consider how to choose the wheels for the tires. First, the owners are determined with the type of rim material: forged, cast are more in demand. It is strictly not recommended to make the wheel heavier, so compare the weight of the rim with that on the machine.

The size of the tire to the size of the rim must be matched to the width. It would seem that it should be the same, this is understandable even without recommendations. But interior rims are selected according to the formula: Ш1 \u003d Ш2х (23% -30%), where Ш1 is the required value of the rim width, Ш2 is the width of the tire. Accordingly, the rim size is selected less than the tire itself by 25 or 30%.

How do I calculate the width?

Let's give an example of calculation based on known tire parameters. Let's take a standard rubber with a width of 195 mm and carry out the selection of disks. A smaller disc is always taken to the tires. Which limit to take, 25 or 30%, depends on the nearest standard value. That is, we multiply 195 by 0.25 and 0.3 and we get 48.75 and 58.5 mm.

According to the correspondence table, which is often presented in inches, we find the closest value. It is more rational to choose a rim width of 5.5 inches, this size is closest to the available tires. Taking a narrower rim is not recommended: there will be strong tread wear. This is due to the sagging of the rubber around the edges.

A narrower tire to rim width will also work poorly. The fit of the rubber in the rim will be loose, making it impossible to use a tubeless mount. With the camera, the wheel will also constantly shift in the lateral direction, which will cause cracks or early wheel failure.

The maximum loads on the tire go during the turn, and here the cord will break with a narrow or wider profile. The appearance of bumps or cracks in the sidewalls will be guaranteed. The lateral rigidity of the rubber is lost. There are standard values \u200b\u200bfor the maximum dimensional deviation:

• For 14 "wheels \u003d 0.5 to 1".
• For 15 "\u003d 1 to 1.5".

Values \u200b\u200bexceeding the specified range reduce the most important parameter of the vehicle's motion - stability. However, the greatest safety can only be obtained when the tire and rim dimensions are perfectly matched.

Diameter

There is a standard ratio of tires to rims. The common disc diameters are 13, 14, 15, 16, 17. Already larger values \u200b\u200brefer to trucks. Car wheels are trying to increase when buying a new car.

Why increase the disk size? The answer is simple: it looks more aesthetically pleasing, big wheels pits pass easier. But the main criterion for choosing a larger diameter is the desire to supply low-profile rubber. It is more suited to speeds and better lateral loads.

When replacing tall tires with low profile tires, the overall wheel diameter does not increase. The dimensions of the rim itself change, and the thickness of the tire decreases. However, the wheel should not change its weight, so light alloy products are preferred over forged ones. Latest Models you need to pick up more carefully.

Installation nuances

It is unacceptable to select the size and type of wheel for the car by eye. It is rare for a person to see a deviation of 2 mm. And such versions of tires and wheels exist. The diameter of the center of the wheel mounting holes must match 100%.

So, the models different manufacturershaving a diameter of 100 mm, there are analogues with dimensions of 98 mm. And often motorists turn a blind eye to this. Such an installation is unacceptable; over time, an emergency may arise due to the destruction of the metal.

When designing a car, the tolerances are set to a minimum in the plus direction. That is, a larger diameter 1 mm from the setting is allowed, but a smaller one is already strictly prohibited. This is due to the fact that there will be differences in the tightening of the nuts. Only one of them will sit properly, the rest will gradually unwind from vibration.

Extra options

Among the many other dimensions of the disc, the main ones can be distinguished: the diameter of the central hole, wheel overhang, types of bolted connections. The first parameter, oddly enough, is observed only by manufacturers of original products. Beautiful alloy wheels are often made universal, so the diameter may be larger than the seat. We have to close our eyes to this for the sake of the original texture of the wheel. The gaps can be closed with the bushings and inserts offered with the disc.

A parameter such as wheel offset is measured relative to the plane of the bolt attachment. This dimension does not affect vehicle handling. A positive offset allows for a fancy wheel shape. However, there are acceptable limits that car manufacturers do not recommend exceeding.

Bolted connections are changed to so-called locks. These are connections with a similar thread, but with a unique key. Without it, attackers will not be able to quickly remove the beautiful wheels. In order to protect your property, you should not save on this. Also, the replacement of bolted connections occurs when the disc offset changes. You will need to choose a longer thread. And you should remember a simple rule: before putting the tire on the rim, try on the rim on seat... Often, a common defect prevents the purchase from being completely installed on the seat.