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 spectacular. To do this, the disk must be larger in diameter. Well, or bought a used car, and the design rims 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.
To begin with, let's remember key parameters wheels.
- 185 - tire profile width in mm
- 65 - percentage of tire profile height to width
- R - designation of a tire of a radial design
- 15 - bore diameter in inches
So, there are several ways to move away from the size of a regular wheel.
1. Wider tire
While maintaining the standard size, we 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 here that all cars are designed for the installation of snow chains with a size of at least 12 mm. Indeed, in some European countries, driving on mountain roads without chains is prohibited, and not a single self-respecting manufacturer will make a car so that it cannot be operated 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. At the same time, the car will become a little softer on the go, and more wide tires improve braking performance.
2. Higher tire profile
We leave it the same, and increase the percentage of the tire 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 the reserve for installing chains). Everything would be fine, but in our particular example, the factor intervenes that tires of this dimension are produced mainly for commercial transport and they are too rigid and expensive to install on a passenger car. However, in other dimensions, the situation may be different.
3. Change the diameter of the disc
The story of a friend's car is very indicative. He bought a Kia Rio with a 1.6 engine and a 6-speed automatic. The regular wheels of the car had a size of 185/65 R15. The owner drove 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 mounting dimensions.
There is noticeably more air between the disc and the tire. The outer diameter of the wheel has also grown (by 9 mm). As a result, the smoothness of the ride has become fantastic. When overcoming the bumps in the road, the car, which was not initially famous for its energy-intensive suspension, began to resemble super-comfortable cars of the log-shaped family on Russian roads. Soft, quiet, smooth. All the problems of dead Russian roads and hard Korean suspension have disappeared. He does not plan to drive, so he does not care about the possible deterioration in road holding at very high speeds.However, a decrease in the diameter of the disc is a very rare occurrence. Much more often it happens that the owner chooses wheels one or even two sizes larger. And "wraps" them in low-profile tires. At the same time, the overall dimensions of the wheel remain almost unchanged or grow within acceptable limits.
It looks impressive, but the smoothness of the ride suffers first of all. Yes, and there are much more chances to damage the wheel on a bad road, because the lower the height of the tire profile, the less the ability of such a tire to withstand shock loads. In everything you need to know the measure. 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 in the wheel arch without any problems, since its outer diameter will increase by only 19 mm. The clearance will grow by a decent 9.5 mm, but you can forget about the softness of the ride provided by the 15-inch wheels of the basic modification.4. Increase the width of the disk and change the offset
A separate story when the owner of the car decides to install wider disks. Some people like it when the wheel protrudes a little beyond the arch. Please note that changing the dimensions of the wheel and tire can significantly increase the weight of the wheel assembly. Such weighting will negatively affect the life of the suspension elements and even the body, since large unsprung masses can cause resonant vibrations that the suspension is not designed for structurally. It is also important to remember 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.
Consequences of increasing the overall dimensions of the wheel:
| pros | Minuses |
| Ground clearance increase. On our roads every millimeter ground clearance on account. If the bottom of the car is 5–10 mm further from the potholes, then there is less chance of damaging it on a bad road. | The wheel can touch body parts. If the wheel width and diameter increase by no more than 24 mm from maximum size wheels recommended by the manufacturer, then this problem is not terrible for you. You can't put chains on after that. |
| Economy improvement. Economy improves slightly country roads, especially on vehicles with gearboxes that have few steps (4 or 5). | Increase in car roll. Yes, the roll will increase slightly, due to the fact that the center of mass is now slightly higher. In practice, this means a slightly lower limiting rearrangement speed. |
| Changing the speedometer and odometer readings. Regular devices always overestimate the readings. You can check with GPS. And with new ones, a little big wheels, the testimony will come into line with reality. Plus or minus you decide. Still, such a discrepancy is made primarily for security reasons. We are for accurate instrument readings. | Decrease in dynamic characteristics. The new wheels are a little harder for the engine to turn, and they themselves are a little heavier. |
| Reducing wheel offset (when the wheels protrude more out of the wheel arches) provides a wider track, which raises lateral stability cars. | Wide disc is easily damaged when touching a curbstone. In addition, if the width of the disk is much larger than the nominal one, the tire carcass does not work correctly. It leads to increased tire wear. |
| In most cases appearance becomes more aesthetic and catchy. | Strongly protruding from the arches of the wheel overload wheel bearings and make driving difficult. It is worth getting the front wheel on the roughness of the road, as the steering wheel literally pulls out of your hands. |
For calculations, it is convenient to use a tire calculator.
Legal aspect
By law, non-standard wheels are prohibited. Therefore, any experiments with the dimensions of tires or wheels are illegal. An exception is if the new dimension is allowed to be installed by the manufacturer. However, in reality, not everything is so scary: if the rims on your small car are not welded to a width of 12 inches, if the diameter is not 19 or more inches, then such wheels will not arouse the interest of traffic police officers. But with obtaining a diagnostic card, problems will already arise.
But what if you put bigger wheels? - examination of the RFIn the process of choosing winter tires no unnecessary questions should arise - in the instructions for the car, the manufacturer clearly gives all the sizes of tires that can be installed. But, wanting to give the car a sporty character, to make it taller and softer, motorists are ready to violate the recommendations of manufacturers. And they break them. And the automakers themselves in the recommendations indicate several different sizes of tires for disks. Larger and wider wheels look more spectacular. But is everything so simple? Let's try to figure out what kind of rubber better in winter- narrow or wide.
What is the profile width?
Before talking about the characteristics of wide and narrow rubber, it is necessary to find out what the width of the profile is and what it affects. So, this is the distance between the side parts of the tire, which is inflated to the usual state recommended by the manufacturer. The profile size and tread width may not always match. However, there is a pattern - the greater the width of the profile, the greater the width and tread. Everyone needs to know this.
Wide and narrow
There have always been disputes about which tires are better in winter - narrow or wide. Thus, fans of narrower tires claim that they have a higher specific pressure with a smaller contact patch with the roadway. The opposite side is sure that wide tires have longer sipes that are responsible for traction in slippery areas.
Experts compared two tire sizes on ice and on snow. So, Nokian Happelita tires with dimensions 205/55R16 and 225/45R17 took part in the experiment. To compare grip performance, four tests were carried out. The car was accelerated on ice, then the braking was checked. Further, acceleration was carried out on snow, followed by a decrease in speed. The test results were mixed. Winter tires should be narrower or wider - it all depends on the characteristics of operation and the climate of a particular region.
On slippery surfaces, wider tires brake best. Due to the sipes, the total length of which is longer, the grip properties on ice are really better. But it can be taken into account that the car was accelerated to 30 kilometers per hour. Braking was carried out from 30 to 5 kilometers per hour. On a packed snow surface, the test results were the opposite. In the snow, the length of the lamellas has little effect. Important role also plays a reduced area of contact with the road. And, therefore, the pressure in the contact patch is also greater. This allows the tire to push through the snow. As for the dynamics of acceleration, then on the snow it is the same.
Test results
Let's see a comparison of narrow and wide winter tires. On snow on narrow tires, the car accelerated to 50 kilometers per hour in 3.66 seconds. On wide - also for 3.66. And here are the results of braking tests - on narrow tires, the car slowed down from 50 to 5 kilometers per hour with a stopping distance of 27.11 meters. On wide the result was - 28.99 seconds.
And here is how the rubber performs on ice. Acceleration on narrow wheels took 3.84 seconds. On the wide car accelerated a little longer - in 3.55 seconds. The braking performance on ice is as follows: the braking distance on narrow ones is 17.91 meters, on wide ones - 17.62 meters. Braking was carried out from 30 to 5 kilometers per hour.
As can be seen from the results, what is wide, what is narrow is about the same, and in different conditions different tires are needed. Therefore, it is difficult to answer the question of which tires are better in winter - narrow or wide.
Wet road tests
The most minimal braking distance on wet pavement is provided by wider tires. In addition, a car equipped with such tires drives better. But as far as aquaplaning is concerned, here the wide tires proved to be bad, much worse than the narrow ones.
Dry winter road
Here, winter tires are not in their element. But, as tests of winter tires (wide and narrow) have shown, the first ones significantly improve the car's handling characteristics and shorten the braking distance. But you have to pay for it in fuel consumption. The wider the rubber, the higher its rolling resistance. This means that fuel consumption goes up.
Spikes or Velcro
It is also a topic of constant debate between motorists. Someone thinks that non-studded winter tires are ineffective in our country, someone thinks the opposite. Let's see what to choose for an ordinary motorist for winter operation car.
Studded tires
In my own way chemical composition Winter tires are much softer than summer tires. But it should be noted that it is rougher, unlike Velcro. Naturally, these tires have special inserts, spikes. You can often hear that these very spikes are erased on the pavement, and also fly out. Yes, indeed, it is. But modern technologies are constantly developing - today you can find the most modern tires on sale that can hide spikes on the pavement. But when the car hits a snowy track, the spike reappears and bites into the ice or snow.
In addition, a water film may be present between the tire surface and the road surface. This significantly reduces tire grip on ice. The spike is teeth that literally cut this film, thereby significantly improving grip. Studded wheels are very popular and effective, which is why they are now sold in huge quantities in countries with harsh climates.
Advantages and disadvantages of studded tires
Reviews say that these tires are distinguished by high grip on ice and snow surfaces under any loads exerted on them. It can be turns, acceleration, braking. They provide shorter stopping distances on icy roads. They have a lot of traction in deep snow.
Among the minuses, reviews highlight high noise, especially when driving on asphalt. In the wet grip is not just bad, but terrible. Due to the protrusion of the stud, the contact area between the tire and the road is reduced. The grip decreases already at a frost of minus 20 degrees - the ice becomes stronger and denser, and the spike is no longer able to break through it effectively. Fuel consumption also increases due to the fact that the tire is very rough. There are slight vibrations on the steering wheel. Spikes often fly out and also grind off. Service life - no more than 4-5 seasons. At first glance, there are more pluses than minuses. But it will not give comfort, as the reviews say. It will give only confidence, high cross-country ability, as well as controllability.
Velcro
Velcro or non-studded winter tires are a completely different thing. She can solve two problems. The tire is able to keep the car on wet pavement with little ice. It can also keep the car on ice. To do this, soft rubber is used so that the tire can stick to pavement. But at the same time, the tire material must also be rigid enough to provide normal handling. Riding on dry asphalt is contraindicated for Velcro - as a result, it overheats. Because of this, controllability will deteriorate. And in all other conditions, these tires are only slightly inferior to their studded counterparts.
Among the advantages can be identified the lack of noise. Fuel consumption will be only slightly more than summer tires. There are no vibrations in the steering wheel, tires behave well on wet pavement. The service life is higher than that of studded counterparts. There are also disadvantages. A car on such tires will be worse controlled on ice and snow compared to spikes. The braking distance on icy roads is also increased. In snow conditions, the permeability is slightly lower.
What's better?
Experts give advice on choosing winter tires. If the region is different harsh winters, then here you need to buy a studded tire. But for the southern regions, you can get by with Velcro. As for parameters such as width, everything is not so simple here.
Narrow tires are needed, for the most part, in order to rut in snow and snowdrifts. Then, when she hits the asphalt, she will hook onto it with spikes. Therefore, narrow tires for the winter are suitable for those places where there is a lot of snow, and the roads are not cleaned. Here, narrow tires will allow you to be king on the road. But there is also a minus - this is a contact patch. Reviews say that narrow tires have a smaller contact patch on hard surfaces. In addition, it is simply uncomfortable to move on ice or icy asphalt on narrow tires.
With wide studded tires in winter, you can be really confident on icy roads, but without snow. The contact patch here is maximum, so the car will hold well on the ice. Significantly increases directional stability from side drift.
Now it’s clear which tires are better in winter - narrow or wide. For most cases, wide is better.
As a rule, for the same car, the manufacturer provides several different sizes of tires with discs of different diameters. The idea is clear: larger diameter wheels are usually more expensive, look more spectacular, and, coupled with the use of lower profile tires, can improve the car's handling to some extent. That is why such wheels are most often offered either as an option or in the most expensive car trim levels. However, when choosing wheels in car dealerships, sales assistants resort to various tricks in order to sell stale wheels. “Just think, the wheels are wider than the standard ones, but the stability will be - wow! Departure size does not match? So plus or minus a centimeter does not play a role! Let's try to figure out what the "game" with the size of the tire and disk is fraught with.
Disadvantages of increasing the diameter of the disks and reducing the profile of the tires - a slight increase in fuel consumption and sensitivity to longitudinal irregularities
WHEEL HEIGHT
Tire sizes offered for a particular car model should not differ greatly in outer diameter - this is one of the main conditions for replacing them. Therefore, when choosing a non-standard wheel, it is best to operate with these special " tire calculators”, which abound on the network. Retreat from standard sizes You can, of course, but be very careful. So, when changing the outer diameter of the tire, the speedometer and odometer readings change. How will this affect the behavior of the car? Most often, motorists use wheels bigger size, wanting to increase the clearance and improve the car's cross-country ability. If we take into account only the change in tire height with the same disc diameter, then in addition to the likelihood of tires grabbing the wheel arches and worsening acceleration dynamics, this can primarily affect comfort: the wheel becomes heavier, and as a result of an increase in unsprung masses, the suspension can work out worse on bumps. In addition to worsening comfort, such a measure will to some extent affect the resource of the chassis elements: the heavier the wheel, the greater the load the suspension is subjected to. On more or less serious SUVs, such “tuning” is usually justified: jeepers are most often ready for a deterioration in both the dynamic qualities of the car and its reliability.
Regarding cars a slight deviation from the standard is allowed - we do not recommend changing the outer diameter of the wheel by more than 3% of regular sizes.
TIRE PROFILE
In any case, when changing the wheel profile to a larger side (and the diameter of the disk to a smaller one), you achieve certain benefits: small and sharp bumps in this case will be more comfortable, and the likelihood of tire sidewall breakdown will be minimized. That is why the use of frankly low-profile tires in many areas of our country does not look particularly justified. As practice shows, the main reason for installing low-profile tires, coupled with larger diameter wheels, is the desire to make the appearance of the car more attractive. In this case, of course, the risk of breaking the sidewall of the tire during sharp maneuvers is reduced, and the car starts to be controlled on bends a little more clearly.
If there is no desire to set records at the Nurburgring, and most of the time driving is supposed to be spent on Russian roads, we advise you to stick to the standard wheel sizes with the disc diameter priority down and the tire profile up. In normal driving modes, this will not greatly affect the behavior of the car, but the improvement in comfort and resistance to breakdown is guaranteed.
WHEEL WIDTH
The issue of choosing a tire width is very complex and requires comprehensive consideration. If summer conditions are taken into account, then wider tires, of course, have certain advantages. The braking distance of wider tires is likely to be slightly shorter, and the passage of a high-speed arc in the limiting driving conditions will be possible at higher speeds. But there are also disadvantages that often outweigh the advantages. For example, an increase in the risk of aquaplaning: due to a wider contact patch with the road, a car with wide tires will “float” on a water-filled highway much earlier. Less significant disadvantages include a slight increase in fuel consumption and a decrease in top speed. Another disadvantage of extra wide tires is increased sensitivity to longitudinal irregularities. On a track, a car with wider tires will obviously be less stable, and its handling will become more “nervous”. By the way, stability and handling are also affected by departure rim. The smaller it is (the wheel “bulges” outward more), the more the optimal wheel break-in shoulder (most often negative) is violated, the more sensitive it becomes to unevenness. steering, and the load on the chassis elements is greater. An even greater danger of an increase in the running-in shoulder is the lack of a stabilizing moment when braking with one of the faulty brake circuits.
The sizes of tires and disks recommended by the manufacturer are designed for a reason - this is your safety first of all. Therefore, here we advise you to adhere to the dimensions given by the manufacturer. Wider is not always better.
If you figured out the size, then you can proceed to the choice of tire model. Today we will consider the tire range using the example of Nitto, a subsidiary of Toyo Tire. And if overseas Japanese tires are in excellent demand, then in Russia (and even in Japan) they are still little known. In the near future, the situation should improve: at the end of last year, the tire company began official supplies of tires to Russia, Kazakhstan and Belarus.
SUV TIRES
Among the Nitto product line there are frankly off-road options (Trail Grappler M / T Mud Grappler), but, as a rule, such products are in demand only among fans of extreme off-road. There are plenty of SUV owners in the country, but not everyone wants to drive off the asphalt. Therefore, for example, if there are no specific requirements for tires such as improving off-road or sports performance, then you should pay attention to the Dura Grappler model - universal tires, created mainly for driving on ordinary asphalt roads and light off-road, successfully combining high tread wear resistance and comfort. A long resource is provided primarily by the tread pattern - its blocks are interconnected, which, in addition to reducing their mobility and premature abrasion, ensures tire stability at high speeds. The tires also feel great in the water element: wide longitudinal grooves effectively remove water from the contact patch, and wavy sipes provide reliable grip on wet roads, while maintaining optimal block rigidity.
Also in the Nitto line there is a comfortable model with a memorable, bright tread design: The NT420S is a high performance tire designed specifically for SUVs. The spectacular asymmetric tread works great both on dry and wet pavement: large blocks on the outer side of the tread increase the contact area of the tire with the roadway, which improves maneuverability and controllability of the car on dry surfaces, while a wide drainage channel and Narrow grooves on the blocks give confident grip on wet roads and reduce the risk of aquaplaning. Separately, we note the possibility of rearranging the wheels from one side of the car to the other, which makes it possible to achieve more uniform wear.
Along with the NT420S, Nitto introduces another model for dynamic and comfortable driving - NT850+ Premium CUV, designed specifically for popular high-performance urban crossovers. According to the manufacturer, the tire provides best performance mainly on wet roads, which is facilitated by four wide longitudinal grooves, as well as transverse grooves, which are located in the shoulder area on the inside and effectively drain water from the contact patch with the roadway. These tires also boast the highest acoustic comfort: the shape and size of the blocks are optimized in such a way as to eliminate the occurrence of sound resonance, and special small notches on the walls of the grooves create an obstacle to air flow and reduce sound vibrations.
CAR TIRES CARS
Nitto car owners also have something to offer. Those who need comfort and reliability from tires, even if the roads do not differ in high-quality coverage, the NT860 model is suitable. The asymmetric tread pattern tire features a double-layer polyester carcass that reduces the chance of punctures and damage, while an optimized rubber layer thickness increases the tire's ability to absorb impacts for even more comfortable driving. In addition, due to the optimized composition of the rubber compound with a high content of silicon dioxide and the addition of special polymers, the tire boasts low resistance rolling and minimal noise.
Owners of premium sedans and business class cars there may be other priorities, among which, most likely, in addition to silence in the cabin and high smoothness, there is excellent directional stability at high speeds. The NT830 line is perfect for such requirements - a high-performance tire with a rather interesting, attractive tread pattern has a number of features. So, the tire design provides good handling and stability at high speed, and noise reduction is guaranteed by special noise-canceling elements located on the sidewall, corrugated drainage grooves, as well as side blocks of various shapes and sizes.
More active drivers will suit another model of the brand - Nitto Neo Gen. Tires with extra high driving performance although they are suitable for a wide range of passenger cars, they are aimed primarily at an active driving style. Wide longitudinal grooves combined with three-dimensional beveled blocks in the center of the tread help maintain wet contact, while wide blocks in the shoulder area on the outside of the tread provide better contact with the road surface when cornering and manoeuvring. Separately, it is worth noting the ability of the tire to work with non-standard suspension settings: since the shoulder area with inside is a single inseparable, and therefore rigid block, this reduces wear on the inner shoulder area of the tread, which usually appears on lowered vehicles with a negative camber angle.
The profile width of a car tire is the distance in mm between the outer sides of the sidewalls of the tire when inflated, and does not include various elevations on the sidewalls, such as markings, finishes, upholstery, etc.
Metric Tire Profile Width
The metric size of the tire profile width is indicated on the tire board in the form of a marking, for example, 225/45 R17, where 225 is the tire profile width in millimeters.
In contrast to the tire profile, which must be calculated in percentage regarding the width of the rubber profile - the width is immediately indicated on the tire. Metric tires can be quickly converted to inches if you need to find the right tires to replace inch tires or to properly fit inch tires to tires with metric width markings. To accurately calculate tire width, remember that 1 inch = 2.54 centimeters.
Inch dimension of tire profile width
The inch size of the tire profile width is most often found in American manufacturers of automobile tires for crossovers, SUVs and sports cars. On the sidewall of an inch wheel, you can find a designation that will indicate the dimension, for example, 31x10.5 R15, where 10.5 is the designation of the tire width in inches. To calculate the metric wheel width, you need to multiply 10.5 inches by 2.54 centimeters, and we get: 10.5 inches \u003d 26.67 centimeters, which corresponds to 265 metric tire sizes.
What affects the width of a tire profile?
What affects the width of a tire profile? - a fairly popular question among car owners who, for one reason or another, would like to go by increasing or decreasing the tire width for their car.
Wide tires - pros and cons
As a rule, the bulk of car owners first of all think about increasing the width of the tire. A wide tire will give the car sporty look, it will look great on any car, but it will not always improve the safety and driving pleasure of a car with wide tires. For each particular car, the optimal tire width is calculated relative to the weight and power of the car and has its own limits, within which any tire width can be installed on the car.
Cons of a wide tire:
- Wheel weight increase
- Increased risk of hydroplaning
- Increase stopping distance on a wet road
- Increase in fuel consumption
- Increasing the load on undercarriage
- Increasing the cost of the tire
Narrow tires - pros and cons
Most often the issue is narrow car tires rises due to lack Money to purchase the sizes recommended by the manufacturer. It is difficult to imagine another reason why a car owner would deliberately go for putting tires on his car narrower than recommended by the automaker. Nevertheless, there are a variety of situations in which narrow wheels may appear on a car. What to expect from the behavior of a car with narrow tires?
Pros of narrow tires:
- Low purchase price
- Steering wheel turns with less effort
- Less hydroplaning effect
- Improved rut behavior
- Reduced wheel weight
- Reduced fuel consumption
- Less rolling resistance
Which tires are better wide or narrow?
To the question: Which tires are better wide or narrow? - you can answer in such a way that for each machine and its operating conditions you need to select best option tire widths, within the limits recommended by the manufacturer. If you follow the recommended dimensions, you can change the width of the rubber with virtually no change in the behavior and safety of the car.
It is possible to follow the path of a significant increase in the width of tires in excess of the recommended sizes if the car has been increased in power, improved driving performance, through the installation of reinforced and improved parts. By increasing the width of the tire beyond the norm, it must be understood that safety on a wet road is significantly reduced, therefore, in this case, a car with wide tires must be used very carefully or completely refrained from using. A significant increase in the width of the tire profile will require an increase in the width of the disk.
The same car can be equipped with large or small rims. But since the outer diameter of the wheel is on the same vehicle must be the same regardless of rim size, the tire with the lower sidewall must be placed on the large rim. This fundamentally changes the characteristics of the car and the vulnerability of the wheels to damage.
For example, a car equipped with 19-inch wheels slowly enters a small depression in the surface made from old paving slabs next to the curb. Carefully, we try to go over the protruding curb by turning the wheel to minimize the risk of scratching the rim. The tire bends, the rim leans back unnaturally and you remove the tire or break the rim! We carefully withdraw. This car is equipped with 245/40 R 19 tires, meaning the sidewall is less than 10cm high. If we could overcome the same obstacle even at 20km/h, we would have torn the sidewall of the tire and damaged the rims.
But if the car was equipped with high profile tires (with a higher sidewall) - say the corresponding replacement - 225/60 R 16 or 215/65 R 16 - this obstacle would be almost completely harmless. A taller tire is more flexible than a lower one, and the edge from the surface is, for example, 15 cm. And here every centimeter matters.
Why low profile tires?
Did you notice that modern cars have wheels with a larger outer diameter than older cars of the same size? However, the increase in rim diameter, the decrease in the height of the sidewalls of the tires and the increase in the width of the wheels (including tires) are especially noticeable. Wider tires are needed to provide efficient acceleration for vehicles with more powerful engines, as well as for effective braking at high speeds on dry surfaces. The use of low profile tires, associated with a decrease in the height of the side wall, also has its justification.
Imagine what happens when a high tire (for example, SUVs) bursts on the highway at a speed of 150 km / h: the car will behave as if it suddenly lost a wheel - left, right, left, right - and the end! It is quite different when the tires are "low": after a sudden loss of air on front wheel the car starts to move to the side, but by adjusting the steering wheel the car can be kept in the lane, and the ESP will help to brake safely.
Less tires = less comfort
The lower the tire, the lower the driving comfort, the more unpleasant vibrations that affect the fatigue of not only the driver and passengers, but also the body, suspension and interior of the car. Therefore, the same car, depending on the size of tires and rims, can have completely different characteristics. Usually the car manufacturer already offers 3 or even more sizes that can be selected at the stage of ordering a car.
If you buy a car with the smallest wheels, this is convenient, but during fast driving it “floats” a little and slows down a little on asphalt. You get bigger rims and the car looks a little better and performs optimally. If you buy the most big wheels, the car ceases to be comfortable, but it behaves most freely during fast driving on a twisty road with good grip, and relies least on curvature.
There are no perfect wheels for all conditions. Wide and low tires, which are ideal on the highway, are no longer ideal in the city where we drive on curbs. When the sidewall of a tire is clearly less than 10 cm, the risk of rim damage and tire burst increases dramatically. The risk is especially high in spring, when the water on the roads often freezes and thaws, resulting in uneven surfaces.
What tires do you need in winter?
For this reason, if you use low profile wheels and rims that more or less fit the car in the summer, it is worth buying a different size for the winter. For many years it has been wise not to change your tire size for the winter, and if you have reasonably sized wheels you can stick with it. However, we drive a little slower during winter and transition periods (especially on motorways), the benefits of low-profile tires are not great, and the discomfort (low suspension) and the risk of failure are high. Low and wide tires in winter can have another disadvantage: on treated snow, their traction (and braking) can be worse than narrower tires.
When choosing the size of car tires, consider several important parameters:
- the diameter of the tire mounting must be compatible with the diameter of the rim, in other words, a 15" rim can only be equipped with a 15" tire, a 16" rim can only be equipped with a sixteenth tire, etc.;
- The tire width must match the rim width. It is not a close relationship, tires of different widths can be placed on the same rim, but the combination of tires and rims must be within the allowable tolerance;
- provided that the rim is of a smaller diameter, you need to check whether such a rim fits. The obstacle can be big stopping support. Brakes depending on the version of the car engine may have different sizes;
- a reasonable choice would be to purchase rims and tires in one of the sizes accepted as part of the first assembly of a factory car.
Recall that the tire profile is the ratio of the sidewall height of the tire to its width. In size 195/65 R 15, the tire height is 65% of 195 mm (or 127 mm), and in size 215/45 R 17, the tire height is 45% of 215 mm - or 97 mm. The height of the tire wall does not depend directly on its profile or on its width. As a general rule, the larger the rim and tire diameter, the lower the tire needs to be to fit the car.