Eli5 – F1 cars have smooth tyres for grip yet on a normal car this would be certain death. Why do smooth tyres give F1 cars more grip yet normal cars less grip?
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My car’s tires were worn down almost smooth when I bought it. Just a little bit of rain and stepping on the gas while driving 65mph caused the back end to break free from the pavement. Driving over a railroad crossing on a curve, even when dry, same thing happened. After getting new tires, I stopped losing grip.
If the surface is dry and not metal, a smooth tire will translate the torque into speed. With metal or wet pavement the torque causes wheel slip
For starters, smooth tires do not equate certain death. The main purpose the tread pattern on a tire serves is to provide a route for water to go through.What this means is that when a tire with a tread pattern rolls over a wet patch of road, it dislplaces and removes the water from the road’s surface, allowing it to have cleaner contact with the road and ultimately more grip under wet conditions. Tread patterns can also increase grip in low grip environments, as is the case with off road tires, where the grooves are bigger and the knobs on the tires sharper and taller, so that mud and dirt can be displaced much like water but also because the treads can dig into soft and loose ground and provide mechanical grip.
In a controlled racing environment however, grip is essential, and the larger the contact patch of the tire the more grip you have, mainly due to the ability to moderate heat better. There’s actually a lot that plays into the overall grip of a tire and not just size but I don’t want to get into it and digress. However it is worth noting that even in racing use, when the weather is bad and the track is wet, grooved tires are also used.
The important thing here is that using a smooth tire on a wet road can lead to what is called hydroplaning, where the tire has no way to remove water from the road surface other than pushing it to the side as it rolls over the road, much like the bow wave of a ship. However this creates the possibility that water is trapped momentarily between the tire and the road surface, which reduces grip significantly and the driver has very little control of the direction of the car. For this reason in most jurisdictions it’s illegal to use “slick” tires on public roads and road legal tires have to have at least some amount of grooves to remove water. What that means is that if you see a smooth tire on a vehicle out on the road, it’s either someone using slicks illegally (unlikely, they’re very expensive and have very low mileage capabilities), or it’s a tire that used to have grooves but has worn down to the point of being smooth, in which case it’s very dangerous since it’s old and worn through, has no ability to remove water, has lost its elasticity over time so it’s harder as well as having worn through the usable part of the tire which means that the internal liners may start coming into contact with the road and that provides very little grip and also the tire may just burst after a point.
**TL;DR** Smooth tires that used to be grooved are certain death. Slick tires are not certain death.
My car’s tires were worn down almost smooth when I bought it. Just a little bit of rain and stepping on the gas while driving 65mph caused the back end to break free from the pavement. Driving over a railroad crossing on a curve, even when dry, same thing happened. After getting new tires, I stopped losing grip.
If the surface is dry and not metal, a smooth tire will translate the torque into speed. With metal or wet pavement the torque causes wheel slip
For starters, smooth tires do not equate certain death. The main purpose the tread pattern on a tire serves is to provide a route for water to go through.What this means is that when a tire with a tread pattern rolls over a wet patch of road, it dislplaces and removes the water from the road’s surface, allowing it to have cleaner contact with the road and ultimately more grip under wet conditions. Tread patterns can also increase grip in low grip environments, as is the case with off road tires, where the grooves are bigger and the knobs on the tires sharper and taller, so that mud and dirt can be displaced much like water but also because the treads can dig into soft and loose ground and provide mechanical grip.
In a controlled racing environment however, grip is essential, and the larger the contact patch of the tire the more grip you have, mainly due to the ability to moderate heat better. There’s actually a lot that plays into the overall grip of a tire and not just size but I don’t want to get into it and digress. However it is worth noting that even in racing use, when the weather is bad and the track is wet, grooved tires are also used.
The important thing here is that using a smooth tire on a wet road can lead to what is called hydroplaning, where the tire has no way to remove water from the road surface other than pushing it to the side as it rolls over the road, much like the bow wave of a ship. However this creates the possibility that water is trapped momentarily between the tire and the road surface, which reduces grip significantly and the driver has very little control of the direction of the car. For this reason in most jurisdictions it’s illegal to use “slick” tires on public roads and road legal tires have to have at least some amount of grooves to remove water. What that means is that if you see a smooth tire on a vehicle out on the road, it’s either someone using slicks illegally (unlikely, they’re very expensive and have very low mileage capabilities), or it’s a tire that used to have grooves but has worn down to the point of being smooth, in which case it’s very dangerous since it’s old and worn through, has no ability to remove water, has lost its elasticity over time so it’s harder as well as having worn through the usable part of the tire which means that the internal liners may start coming into contact with the road and that provides very little grip and also the tire may just burst after a point.
**TL;DR** Smooth tires that used to be grooved are certain death. Slick tires are not certain death.
For starters, smooth tires do not equate certain death. The main purpose the tread pattern on a tire serves is to provide a route for water to go through.What this means is that when a tire with a tread pattern rolls over a wet patch of road, it dislplaces and removes the water from the road’s surface, allowing it to have cleaner contact with the road and ultimately more grip under wet conditions. Tread patterns can also increase grip in low grip environments, as is the case with off road tires, where the grooves are bigger and the knobs on the tires sharper and taller, so that mud and dirt can be displaced much like water but also because the treads can dig into soft and loose ground and provide mechanical grip.
In a controlled racing environment however, grip is essential, and the larger the contact patch of the tire the more grip you have, mainly due to the ability to moderate heat better. There’s actually a lot that plays into the overall grip of a tire and not just size but I don’t want to get into it and digress. However it is worth noting that even in racing use, when the weather is bad and the track is wet, grooved tires are also used.
The important thing here is that using a smooth tire on a wet road can lead to what is called hydroplaning, where the tire has no way to remove water from the road surface other than pushing it to the side as it rolls over the road, much like the bow wave of a ship. However this creates the possibility that water is trapped momentarily between the tire and the road surface, which reduces grip significantly and the driver has very little control of the direction of the car. For this reason in most jurisdictions it’s illegal to use “slick” tires on public roads and road legal tires have to have at least some amount of grooves to remove water. What that means is that if you see a smooth tire on a vehicle out on the road, it’s either someone using slicks illegally (unlikely, they’re very expensive and have very low mileage capabilities), or it’s a tire that used to have grooves but has worn down to the point of being smooth, in which case it’s very dangerous since it’s old and worn through, has no ability to remove water, has lost its elasticity over time so it’s harder as well as having worn through the usable part of the tire which means that the internal liners may start coming into contact with the road and that provides very little grip and also the tire may just burst after a point.
**TL;DR** Smooth tires that used to be grooved are certain death. Slick tires are not certain death.
Some road cars do come with tires that are pretty much slicks. Look up Michelin Cup 2 tires. As others have noted, the grip in wet conditions, especially in RWD cars is atrocious and dangerous. Not to mention tread life is abysmal and they are expensive to replace. They also can only be used in the summer which necessitates having a second set of wheels for winter. The only real benefit is grip in the dry and when temps are warm enough. The only kind of cars that need this grip are high performance sports cars. For the vast majority of cars on the road, the cons significantly outweigh the pros, hence why most road cars don’t use them.
Some road cars do come with tires that are pretty much slicks. Look up Michelin Cup 2 tires. As others have noted, the grip in wet conditions, especially in RWD cars is atrocious and dangerous. Not to mention tread life is abysmal and they are expensive to replace. They also can only be used in the summer which necessitates having a second set of wheels for winter. The only real benefit is grip in the dry and when temps are warm enough. The only kind of cars that need this grip are high performance sports cars. For the vast majority of cars on the road, the cons significantly outweigh the pros, hence why most road cars don’t use them.
Some road cars do come with tires that are pretty much slicks. Look up Michelin Cup 2 tires. As others have noted, the grip in wet conditions, especially in RWD cars is atrocious and dangerous. Not to mention tread life is abysmal and they are expensive to replace. They also can only be used in the summer which necessitates having a second set of wheels for winter. The only real benefit is grip in the dry and when temps are warm enough. The only kind of cars that need this grip are high performance sports cars. For the vast majority of cars on the road, the cons significantly outweigh the pros, hence why most road cars don’t use them.
Smooth (or to use the automotive term, slick) tyres give huge amounts of grip, but only under a set of very specific conditions.
In particular they only work in dry conditions, and with a good quality, clean track to drive on, and soft, sticky rubber compounds – this allows all of that rubber to be in good contact with the ground, and the more rubber in contact, the more grip you have.
The problem is that if those condition change, a slick tyre will very suddenly lose traction and become dangerous. If it starts to rain for example, all it takes is a thin film of water to act as a barrier between the tyre and the road, and grip vanishes. Similarly if the road is rough or covered in debris like mud and gravel, that also creates a barrier between the tyre and the road.
The solution to this is a treaded tyre. These are tyres that have patterns of grooves cut into the surface of the tyre.
Under ideal conditions, the grooves mean slightly less rubber will be in contact with the road, so they will have less grip than a slick tyre. But as soon as conditions are less than perfect and you encounter a wet, muddy or rough road, the grooves act as channels to allow the tyre to clear water and debris out of the way and keep the rubber in contact with the ground.
The end result is that when you have a controlled situation – a clean track, and the ability to swap tyres halfway through a race if it starts to rain and you need treaded wet weather tyres, or when your soft rubber starts to wear out, then slick racing tyres will give the best performance.
If you are driving out on the public road however, you don’t have the chance to swap tyres halfway through a journey if it rains, the roads are unpredictably uneven and dirty, and you want a harder (less grippy) tyre that lasts for thousands of kilometers, not just hundreds, then you make the compromise of using a typical all weather, treaded tyre.
In fact, using slick tyres in poor weather is so dangerous, a lot of countries ban their use on public roads, and require suitably general use tyres be used.
Smooth (or to use the automotive term, slick) tyres give huge amounts of grip, but only under a set of very specific conditions.
In particular they only work in dry conditions, and with a good quality, clean track to drive on, and soft, sticky rubber compounds – this allows all of that rubber to be in good contact with the ground, and the more rubber in contact, the more grip you have.
The problem is that if those condition change, a slick tyre will very suddenly lose traction and become dangerous. If it starts to rain for example, all it takes is a thin film of water to act as a barrier between the tyre and the road, and grip vanishes. Similarly if the road is rough or covered in debris like mud and gravel, that also creates a barrier between the tyre and the road.
The solution to this is a treaded tyre. These are tyres that have patterns of grooves cut into the surface of the tyre.
Under ideal conditions, the grooves mean slightly less rubber will be in contact with the road, so they will have less grip than a slick tyre. But as soon as conditions are less than perfect and you encounter a wet, muddy or rough road, the grooves act as channels to allow the tyre to clear water and debris out of the way and keep the rubber in contact with the ground.
The end result is that when you have a controlled situation – a clean track, and the ability to swap tyres halfway through a race if it starts to rain and you need treaded wet weather tyres, or when your soft rubber starts to wear out, then slick racing tyres will give the best performance.
If you are driving out on the public road however, you don’t have the chance to swap tyres halfway through a journey if it rains, the roads are unpredictably uneven and dirty, and you want a harder (less grippy) tyre that lasts for thousands of kilometers, not just hundreds, then you make the compromise of using a typical all weather, treaded tyre.
In fact, using slick tyres in poor weather is so dangerous, a lot of countries ban their use on public roads, and require suitably general use tyres be used.
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