Ten signs of tire wear that can tell you about the condition of the car. Uneven tire wear - what could be the cause? Diagonal dent showing signs of tread wear

As soon as the tire manufacturers did not explain this sad fact. But all the "specialists' comments" usually came down to one thing: the owner of the car is to blame - he carelessly drives on rough roads; overloads the car, does not follow the angles of the wheels, tire pressure, balancing ...

A conscientious motorist, having read or heard something like this, is surprised: “I monitor the pressure, I don’t overload the car, the wheel alignment and balancing are in order ... As for “carelessness”, I didn’t even bend flimsy iron disks! And still I lost count of crooked tires. Others and 25 thousand weren’t cared for - the tread is still somewhere, but it’s impossible to drive. By the way, gentlemen, tire manufacturers, why does this almost never happen with the products of your foreign competitors?

Let's first of all remember why a tire - unlike, for example, a tube - retains its size and shape, even if it is overinflated? Yes, because, as everyone knows, it is not only made of rubber! The almost inextensible cord frame largely determines the strength, wear resistance, mechanical losses during rolling and a number of other important properties of the tire.

The modern radial tire (Fig. 1) owes its name to the fact that the cord threads of the main (from bead to bead) carcass 1 are located in radial planes and do not intersect, as in the previous diagonal ones. This cord is usually textile.

The crown zone of the tire, which experiences increased loads, is additionally reinforced by a power ring - a metal cord breaker 2. Its cord threads - cables twisted from several steel wires, with a brass coating for better adhesion, are not laid radially, but at a certain angle to the plane of rotation of the wheel several layers. The design is like a grid.

Its width almost corresponds to the tread, the ends of the threads are free - they are not tied to anything. But after vulcanization, the breaker is practically inextensible, although it is quite flexible. This allows the tire to roll normally. Such tires consume less energy (that is, fuel), the car with them is more manageable, their tread lasts longer, etc. But all these pluses are easily crossed out by one minus. It is worth breaking the bonds between the cord and rubber - and the breaker is bent. The tire, they say, went screw. And then, even with a still very decent tread, there is nothing left but to part with it.

BEGINNING OF THE END

The destruction of a tire hurts the car owner's pocket. Noticing that the car began to shake at low speed, an experienced motorist will become sad. Stop and check the wheels. Here it is the reason: one of the tires seemed to be bent!

Let's look at an example. An openwork bicycle wheel (Fig. 2) with thin spokes, however, has sufficient strength and a stable shape ... only under certain conditions, when all the spokes are of the same length and equally loaded (Fig. 2a). (More complex schemes are not considered here.) If at least one or two spokes burst, the symmetrical balance of forces is violated (Fig. 2b). Loads will begin to be redistributed, serviceable spokes pull the hub towards themselves, the wheel changes shape until a new balance of forces occurs. But now the spokes near the broken ones are heavily overloaded. And in turn, they can break. The wheel is deformed even more.

Approximately the same thing happens if the cord bursts. Or exfoliate from the rubber and "creeps". This tire is not suitable for use. It becomes a source of unrecoverable shaking (the naive try to "balance" it, not considering that an irregularly shaped wheel, even balanced, still shakes!), The curvature progresses, the tire collapses faster and faster, and this can end with an explosion on the go! (As a rule, an exhausted motorist throws out a tire much earlier.)

RISK FACTORS

Many do not even suspect that a single puncture often ruins a steel cord tire if dirty, salty water gets into the hole. As a rule, this happens to those who prefer wheels with cameras. They got used to acting like this: seal the camera and not think about the tire - well, what will happen to her! By the way, even textile cord can "rot" in its own way. And metal - even more so. Often, after a year, only rust reminds of the wires near the puncture site. ("By opening" such a tire and carefully cutting off the tread to the cord, this is easy to verify.). The breaker, which has lost part of the cord, is bound to bend - we have already named the reasons. The moral is simple: it is desirable to seal any tire puncture, although, of course, this is unnecessary trouble.

Another risk factor is air pressure. To follow him is in the interests of the owner. Reduced (most often the wheels are lowered by a loafer!) not only increases fuel consumption, reduces speed, etc., but also accelerates tire wear, in particular, the carcass cord and broker, which additionally "breaks" in a crumpled tire (Fig. 3). and suffers more from fatigue. In addition, during the operation of an under-inflated tire, much more heat is released - additional energy is spent on its deformation (and on internal friction between rubber layers). The tire heats up intensively, and when the temperature inside, between the layers, "goes off scale" over 120 ° C and crawls further, irreversible damage cannot be avoided. The strength of the cord, especially textile, is sharply reduced, bonds are destroyed, the tire is stratified.

The next enemy of the steel cord broker is a strong blow concentrated in a small area. If you run into a sharp stone at full speed, the advantages of the metal cord become disadvantages: the high modulus of elasticity of steel does not allow the wires to stretch a little for a moment, to smooth out the blow. And weakened by corrosion or wear, they can simply burst.

By the way, what kind of wear are we talking about? From the "killed" tire, with wires sticking out from under the tread, remove one with pliers. And take a look. It looks like a thin "gimlet"! Worn out by friction on neighboring ones. Let's calculate how many revolutions does the "Zhiguli" wheel make per kilometer of the way? About 600. And for 10 thousand? .. The bill went into millions? That's how many times, at least, the wire moved, rubbed against the neighboring ones! We don’t talk about bumps in the road that increase this score ...

This means that, like a car as a whole, an “older” tire is weaker than a new one and needs to be treated more carefully. The fact that a new, two-year-old one - even with a good, it seems, tread - will easily finish off. And do not forget about latent corrosion: some damage to the tire - in the form of deep cuts - exposes the cord, but the owner does not know about them, since there is no through hole.
In a word, those who are not spoiled by extra money should be attentive to the surprises of our roads. I left on a broken surface - immediately slow down. I saw a scattering of bottle fragments - try not to run over. And you ran over - check the tires: are they intact, are there pieces of glass sticking out of the tread? To remove them in time is sometimes to save the tire.

Gennady Ivanov "The process has begun ..."
Magazine "Behind the wheel", 2002 №3

Rubber is used in many household structures: various hoses, seals, adapters, car parts. Over time, products made from this material fail, dry out, lose elasticity, and become inconvenient to use. You should not immediately buy new elements, you can try to soften the rubber at home.

Remanufactured rubber part using kerosene

Rubber elements under the influence of external factors lose their original properties, become less elastic, harden. Their further use will not bring the desired effect, seals, for example, will not be able to make the system completely sealed. The purchase of new rubber elements is sometimes difficult due to the lack of products of the required dimensions or their overpriced.

The following substances allow you to soften rubber:

1. Kerosene. Allows you to make rubber parts soft by affecting the structure of the material. After processing, the rubber element becomes fully elastic. Recovery technology is as follows:

• fill a small container with kerosene (choose the container size depending on the size of the product to be restored);
• place the part in a container with kerosene for 3 hours;
• after the specified time, check the product for softness, if the result is satisfactory: remove the material and rinse with warm running water;
• dry the material in a natural way, without using a hair dryer or battery.

1. Alcohol ammonia. The process of restoring old material is as follows:

• dilute the indicated alcohol with water in a ratio of 1: 7;
• place the rubber material in the resulting solution for half an hour;
• after the specified time, remove the part and rinse with warm running water;
• Allow the parts to dry completely before using them.

Please note: you can not keep rubber in a solution of ammonia and water for more than an hour. If the material does not become elastic after 30 minutes, use another recovery method.

1. Medical alcohol followed by the use of glycerin. The technology of "reanimation" of rubber parts:

• fill the container with medical alcohol;
• put in alcohol a part that needs to be restored for several hours;
• after the specified time, check the condition of the product, if it is soft enough, remove the element from the solution and wash it with warm soapy water;
• rub glycerin into the surface of the part using a sponge (cloth);
• remove any remaining glycerine from the surface of the product.

Instead of glycerin, it is allowed to use automobile oil, it is rubbed into the surface of the product, then the part is kept for half an hour before use. During this period, the rubber becomes sufficiently elastic.

1. Castor oil and silicone. Let's make a reservation right away - this method allows you to quickly "reanimate" the old rubber, but the recovery effect will not last long, after a few days the product will become solid. For this method, follow the sequence:

• smear the part with silicone;
• wait 10 minutes;
• after the specified time, the part can be used.

Note: a similar effect is achieved by using castor oil. It is rubbed into the surface of the part, after which it becomes soft and elastic.

Heating is an effective method

Container with prepared water for boiling rubber products

There are situations when the rubber element is difficult to remove from structural parts due to its hardening. You can achieve the desired result by heating the rubber with a stream of hot air using a hair dryer. When exposed to high temperature, the material will become softer, it can be pulled out of the part.

Too "hardened" element is softened by boiling in salted water. The technology is as follows:

• fill the container with salted water;
• let the liquid boil;
• place the rubber element in boiling water for 10 minutes;
• remove the rubber and quickly use it for its intended purpose.

This method is quite effective, but has a short-term effect. When it cools down, the rubber becomes stiff again.

Conclusion

You can soften the rubber in the above ways. In this case, it is necessary to take into account: a long-term effect after restoration, has a method with kerosene. Rubber, after its application, remains soft and elastic for a long time, because the structure of the material changes. Other methods do not allow to achieve such a result.

Vehicle tires are the only element vehicle which connects it to the road. Often car owners forget that rubber is the most important element of a car that directly affects. But when the tires wear out, every driver regretfully understands that it's time to spend money on buying new tires. . After all, sometimes tire wear can indicate a possible malfunction of the car. In this case, replacing the rubber with a new one may not help. For example, with some types of breakdowns, your new tires may wear out prematurely in a short time. Let's take a look at ten of the most by which it is quite possible to determine the cause of this wear and tear, eventually finding out the technical condition of the vehicle.

1. Wear of the rubber tread in the center (in the middle)

What it looks like: With this type, as a rule, the tread in the middle of the tire is worn the most (example in the photo).

Cause: If the tire wears the most in the center of the wheel, then this indicates that the central part of the tread had the most contact with the road surface, compared to the tread closer to the edges of the rubber. Therefore, the car on which this rubber was installed did not have sufficient grip with the road surface. Accordingly, the traction of the machine was insufficient.

Most often, such wear indicates that the tire was not properly inflated. That is, the tire pressure did not correspond to the pressure recommended by the car manufacturer. This type of wear indicates that the owner of the car did not check the pressure even with sudden changes in temperature outside, at which the pressure in the tires can change significantly.

The fact is that while the tires are cold (for example, after a frosty night), the tire pressure may be lower than the manufacturer recommends. But after the start of the movement, the pressure in the tires begins to rise from the heating of the air in it. As a result, after a certain distance traveled, tire pressure may exceed the maximum allowable rate recommended by the automaker. As a result, the pumped-over unevenly adjoins to pavement resulting in uneven tire wear in the center of the tread.

Some motorists often advise to improve handling and reduce fuel consumption, on the contrary, to pump over the wheels. But this is not justified. Yes, in this way you can reduce fuel consumption a little and even improve handling a little, but in the end you will pay for it with faster tread wear.

That is, saving a little money on fuel, you will pay a lot more.

2. Tire bulging (bulging) and side wall cracks

What it looks like: Cracks and bulges on the side wall of the tires.

Cause: This usually comes from hitting a pothole (hole) in the road, a curb, etc. Usually the tire is well protected from such impacts. But if the tire is under-inflated or over-inflated, there is a great danger that the tire will be damaged as a result of the impact. Large cracks on the side wall of the tire that run along the rim of the wheel indicate that it has been operated with insufficient pressure for a long time. Small cracks on the side surface of the rubber indicate external damage or the age of the rubber (due to age, the rubber compound begins to chemically break down, causing the tire to begin to crack).

A herniated tire looks like a bulge on the surface of the rubber. Most often, a protrusion (hernia) appears on the side wall of the tire. Herniated rubber is associated with internal damage (rubber layer). This usually happens due to a side part hitting a curb, pole, etc. Most often, after an impact, a hernia (protrusion) of the wheel does not immediately appear. That is, after a stroke, you can see a hernia only after a week or even after a month.

If you notice cracks or hernia on tires, then you need to buy new tires as soon as possible.

Remember that it is very dangerous to use rubber with a hernia..

3. Dents in rubber

What it looks like: According to long-term observations, rubber with dents looks like in the photo. That is, the tire has the form of tubercles and dents.

Cause: This type of tire is usually associated with (wear or damage to the elements of the chassis of the car). Due to a malfunction of the suspension, shock mitigation on bumps is insufficient. As a result, the tire experiences an overload from impacts, taking on the maximum load. But the load is distributed unevenly over the entire tread surface. As a result, some areas of the tread take on more load than others, which contributes to the formation of dents and bumps on the tires.

Most often, this appearance of used tires is associated with poor shock absorbers. Although it is worth noting that any parts of the suspension that have failed can cause this kind of wear.

We advise you in case of detection of such deformation of the tires, to make a complete suspension and racks of the car in the technical center. We do not recommend dealing with a similar problem at a tire fitting, i.e. in order to determine the cause of the change in the shape of the wheels. It is not uncommon when tire workers do not know what can cause irregularities (dents, bumps) on the tread surface.

Most often, tire workers claim and believe that this is the cause of improper camber. But this is not a fact. As we have already said, this reason may be due to the failure of the shock absorber (s).

4. Diagonal dent with signs of tread wear

What it looks like: Diagonal dent on the tread surface with uneven wear on the tire surface.

Cause: Most often this problem occurs on the rear wheels, where the camber is incorrectly set. Also, a similar deformation of the wheel can be associated with an insufficient rotation interval, and also, sometimes a similar change appearance tires may be associated with the frequent transportation of heavy loads in the trunk or in the car.

A heavy load can change the geometry of the suspension, resulting in diagonal deformation of the rubber tread surface.

5. Excessive tread wear at the edges

What it looks like: The inner and outer tread has increased wear, while the middle of the tread is significantly less worn.

Cause: This is a sure sign of insufficient. That is, the pressure does not correspond to the norm recommended by the car manufacturer. Remember that this is the most dangerous tire condition. The fact is that with reduced pressure in the tire, it is subject to greater bending. According to the laws of physics, this means that when the wheel rotates, the tire will accumulate more heat. As a result, the rubber will not evenly adhere to the road surface and, accordingly, we will get uneven rubber wear.

Also, insufficient pressure in the tires will lead to the fact that the rubber will not sufficiently soften the blows on the road, which will naturally directly affect the suspension. Over time, this hard impact on the suspension can lead to premature suspension failure, as well as affect the wheel alignment.

How to avoid the problem of under-inflated (insufficient pressure) tires: We again return to the fact that every driver should regularly check the air pressure in the tires, that is, every month or every time after a sharp change in temperature outside. Also remember that cold tires (when parked at night) may show pressures lower than those recommended by the vehicle manufacturer. But during a long trip, due to the heating of the air, the pressure may exceed the norm.

The fact is that this system usually warns you of a change in tire pressure, either when there is a sharp pressure fluctuation (for example, a sharp drop in tire pressure by more than 25 percent), or when there is a significant decrease in pressure for a long time.

In other words, the tire pressure warning system can only be activated when the tire pressure is significantly lower than necessary. This means that you run the risk of driving for a long time on wheels with insufficient air pressure.

6. Convex side tread wear

What it looks like: The side blocks of the tread, usually similar to the plumage of birds, have. The lower edges of the tread blocks are rounded, while the higher edges of the blocks are sharp. Note that you cannot visually notice this kind of wear. This can be understood only when examining the tread from the edge and by touch, i.e. with hands.

Cause: With this type of tread wear, check the ball joints and wheel bearing first.

It is also necessary to check the stabilizer bushing, which, in case of failure, can lead to improper operation of the suspension stabilizer, which will eventually lead to this type of wear on the rubber tread.

7. Flat wear spots

What it looks like: One spot on the wheel has more wear than the other.

Cause: Single spots of increased wear on the surface of the tire are often found when forced to hard brake or skid, or when taxiing out of a situation in order to avoid an impact (for example, if an elk or other animal did not unexpectedly run onto the road). Especially such wear will be visible after heavy braking with simultaneous skidding, if the car is missing.

The fact is that when braking hard and steering away from the impact, a car without ABS is more prone to skidding with locked wheels, which will lead to something like this kind of worn spot on the tire tread.

Also, similar stains can appear in cars that have been parked for a long time.

Remember that when you park your car for a long time, you risk tires where wear spots will appear on the tires of your car due to the uneven distribution of the weight of the car on them. The fact is that during parking, the rubber tread does not completely come into contact with the surface and, as a result, a certain section of rubber is deformed from a long parking.

8. Wear on the leading edge of the tread

What it looks like: The leading edge of the tread block is worn and the rear of the tread has sharper corners. Please note that this type of wear may not be visible during visual inspection. Therefore, check the protector with the edge by hand. If you notice that some tread corners are sharper (like hacksaw teeth) compared to other tread edges that are smoother, then this is real wear and not the norm, as many drivers usually assume.

Cause: This is the most common tire wear. Since this type of tire wear is very common and many car owners think that this is the norm, it is not. In fact, this wear indicates that the wheel has insufficient rotation. Therefore, it is necessary.

Most often, the reason is associated with the wear of the suspension elements (salint blocks), with the wear of the ball bearings, and also due to the wear of the wheel bearing.

9. Unilateral tire wear

What it looks like: One side of the tire is worn more than the other.

Cause: Usually, with this type of wear, the cause may be an incorrect alignment of the collapse of the car. This type of uneven wear of the rubber tread is due to the fact that it does not stand exactly on the road surface due to improper wheel alignment.

In order to set the wheel exactly in relation to the road surface, it is necessary to adjust the wheel alignment.

Also, similar wear can occur with damaged springs, ball joints, suspension bushings. In particular, one-sided uneven wear of the tread may appear when transporting heavy loads by car.

In addition, some models of powerful sports cars have a special wheel alignment, which leads to a similar uneven tire wear. But this is rare.

10. Tire wear to indicator

What it looks like: Many tires have wear indicators between the tread. As a rule, these are special inserts that help you determine when it is necessary to change tires for new ones. Usually the height of these inserts is lower than the height of the tread. As soon as the tire tread is equal in height to the wear indicators, it is necessary to purchase.

Cause: Typically, tire replacement should occur after the tread depth is lower than recommended by the tire manufacturer. It's not always easy to tell by eye. Therefore, many tire manufacturers install wear indicators on tires (between the tread). As soon as the tread height wears down to the height that the indicators have, then it's time to change the wheels to new ones.

A rubber tread with a certain depth is necessary in order to divert water from the tire and prevent the car from hydroplaning on wet roads.

If your tires do not have a wear indicator, then you can measure the tread depth yourself in order to understand whether it is time to buy new tires. To do this, you need to use a coin, which must be inserted into the tread with an edge and measure the depth with it. You can read more about traditional tire wear here or check out our infographic.

Attention! For summer tires minimum depth tread must be at least 1.6, 2 or 3 mm (depending on the rubber manufacturer).

For winter tires the minimum safe tread height should be at least 4-6 mm

Rubber is considered one of the most common materials today. Over time, the main characteristics can be significantly reduced. A fairly common question is how to soften the rubber. A similar procedure can be performed independently at home, it is important to follow all the recommendations.

Do-it-yourself rubber restoration

All materials lose their performance over time. Often you can find a situation where the rubber becomes too hard and loses its elasticity. If desired, you can restore the basic properties of the material, it is not necessary to throw it away. Rubber can be softened in a variety of ways. Among the features of this issue, we note the following points:

1. Rubber cuffs and seals of some devices lose their basic properties over time. In this case, you can buy new consumables, since their cost is relatively low.
2. Some elements are difficult to find on sale, due to their unusual shape and properties. In this case, softening can be carried out using various common technologies.

There are quite a number of different ways to soften rubber, the most common is the use of kerosene.

What is needed to restore the elasticity of rubber?

Rubber is considered one of the most resilient materials. It is for this reason that it is used in the manufacture of various seals. After the seal ceases to be affected by the load, it is able to return to its dimensions. This moment determines the spread of the question of how to restore the elasticity of rubber. Over time, this property is also lost. If the surface is worn too much, cracks appear, due to which the insulating qualities are significantly reduced.

You can soften rubber at home using common substances. The most commonly used substances are:

1. Kerosene can easily restore the elasticity index. This substance is ideal for processing small products; you can soften them by soaking them.
2. Ammonia can be used to soften the structure. To do this, it is enough to create a small bath in which the product is lowered for several hours.

When soaking rubber in a recovery liquid, it should be borne in mind that the material can increase significantly in size. To remove the substance from the surface, the product is thoroughly washed with soap and water.

In some cases, you can use hot water to soften rubber. This method is used to restore the insulation of the doorway of the refrigerator. You can enhance the effect achieved by wetting the surface with silicone.

Seals from the material in question are also used in the manufacture of windows. To improve the insulating qualities of the rubber bands, they are wiped with silicone and glycerin from time to time. Such substances can be purchased without any problems.

How to give elasticity to rubber?

1. Rigidity increases if the rubber is kept dry for a long time. Elasticity is restored by wetting the surface with oil. Softening is recommended to be carried out periodically to achieve the desired result.
2. Car wipers can be lubricated with silicone grease, due to which the surface is softened. Of course, it is possible to restore the old structure only if there are no mechanical defects.

In addition, on sale you can find special compounds that can soften the structure after application.

How to soften rubber at home?

At home, you can soften rubber by using various materials. The most widespread are:

1. Kerosene.
2. Castor oil and silicone.

High temperatures also cause the rubber to become softer, but the wear resistance decreases.

Kerosene

When considering how to soften rubber, many give the possibility of using kerosene. Such a substance is able to restore the elasticity index.

Application features are that the product is soaked in a special bath, after which the surface is thoroughly washed and dried. If the length of the product is large, then it can be rolled up. Aged in kerosene to soften for several hours, as kerosene does not act immediately.

This substance is widely used, it can also make the product softer. The procedure is as follows:

1. A container of a suitable volume is selected.
2. Ammonia is diluted in water to obtain the required solution.
3. The product is placed in the solution for an hour to soften.
4. After that, the softened element is taken out and washed with clean water.

Drying is carried out at room temperature. It should be borne in mind that high and low temperatures always negatively affect the condition of the rubber.

Silicone and castor oil

A short-term effect can be achieved if silicone and castor oil are used. Among the features of the application, we note the following points:

1. Silicone has only a temporary effect. It can be purchased in specialized stores.
2. After lubrication, you need to wait a while. Silicone can be absorbed into the structure, making it more elastic.

After half an hour, the rubber will be ready for use. It should be borne in mind that the achieved effect will be temporary. When considering how to soften such material, you can pay attention to castor oil.

The heating

In some cases, only a temporary softening is required, for example, when putting a hose on a nozzle. In this case, you can solve the problem by temporarily lowering the product into a hot bath. After some time exposure to high temperature, elasticity increases.

With prolonged use, the rubber can become dull. Problems can only be solved if the product is boiled. Significantly increase the effectiveness of the procedure by adding salt to the composition. Boiling is carried out until the moment when the surface becomes elastic.

If there are difficulties in removing the tubes and hoses, then the heating is carried out by exposure to a warm air stream. For this, a building or ordinary hair dryer can be used. When the high temperature air flow is concentrated in one place, plasticity increases significantly.

In conclusion, we note that only in the absence of defects can the restoration of the material be carried out. Some recommended methods may result in some performance degradation. That is why you need to follow all the recommendations.

I know from my own experience that not all rubber products can be restored; to give them their former elasticity and softness, after it has hardened. In general, a small part of rubber can be brought back to life if we are talking specifically about rubber, and not about the latest polymers, which do not lose their physical properties at a certain operating temperature.

The whole difference is that rubber products, namely the "rubber" material itself, in the course of its manufacture, undergoes such a process as vulcanization, when the base of rubber - rubber turned into rubber when interacting with certain substances at a certain temperature. Rubber was a new material in which rubber molecules created a single spatial grid, it is due to this single grid that rubber has its physical properties.

It will not be practical to talk about all rubber products in one recommendation, since there are a lot of rubber types and each rubber has its own incoming properties, as well as the degree of saturation of the rubber, the ability to crystallize and orientate, the strength of the chemical bond chain and the flexibility of macromolecules.

Basically, 5 main factors influence aging and loss of elasticity:

• light exposure, in which the irreversible process of photooxidation of rubber occurs.
• ozone exposure, which results in cracking of stressed rubber.
• thermal action destroys the spatial grid.
• radiation exposure destroys the bond of molecules.
• vacuum action breaks separate sections in the product.

All this negative influence leads to the fact that the rubber becomes hard and / or brittle. If the product crumbles, then it will not work to give it elasticity, since the bond between the molecules is broken.

But if the rubber has hardened, but has not begun to break down, then it can be brought back to life.

One of the misconceptions is that many advise to dip or spray the product with solvents, gasoline or alcohol. This cannot be done, because, firstly, there is oil-benzo resistant rubber, which simply will not accept these liquids, and secondly, other rubber products simply dissolve partially or completely in these solvents, and the elasticity effect will be only temporary.

But one of the really effective solutions that can "revive" rubber products is ammonia solution with 5% concentration.

In this solution, the product should be held for no more than 15 minutes, then, if possible, knead it by mechanical pressure and treat it with the following composition.

Place the product after softening in water-glycerin solution with 5% concentration.

In this solution, the product must also be held for no more than 15 minutes.

The temperature of the solutions should be in the range of 40-50 degrees.

There should not be much time between the two solutions, since ammonia will destroy the rubber with prolonged exposure, and glycerin in water slows down this process.

Ammonia solution 5% is not on sale, for this reason you will have to buy 10% and dilute it with distilled water according to the formula (see chemical formulas, I personally can make a mistake)

A water-glycerin solution of 5% is also not on sale, there is only pure glycerin or 85%, it must also be diluted to obtain the appropriate concentration.