Sometimes I noticed inconsistencies in the behavior of tires in LFS and in reality. idk, maybe it can help the development of the game. It's not that I think Sсawen didnt knows this, but just in case I want to share what I've noticed about tire physics as drifter and why it doesn't always match what I see in reality.

1. Wear. We have always noticed on race circuits that tires pop if we keep the temperature at normal values and wear out one of sides of the tire. But also in drifting, people often noticed that the tire pop from over 200 degrees. In real life drifting, it doesn't work quite like that, in drifting the tires grind down to the cord and lose the grip almost completely, since there almost no rubber and is only metal left. But in LFS there is no cord effect. (pic1)

Most experts consider 195 degrees Fahrenheit as the “line in the sand” when it comes to tire temperature: Beyond that point, the temperature will start impacting tire life. At 250 degrees, a tire will start to lose structural strength, could begin experiencing tread reversion and the tire will begin to lose strength.

But still it doesn't happen instantly like in LFS at a certain temperature, in real It's more about wear. And you can pop only after the cord, and this moment is immediately felt cuz there is almost no grip on cord.

2. Grip/temperature. Many people know that the tire has a "operating range" This is the temperature of the tire where is grip with the surface is greatest. Before OR and after OR there is a decline in the grip. And the grip gradually drops to not very good and not very bad until the wear runs out tire to the cord and here already the grip falls dramatically until tire pop.

In LFS, the temperature before OR is similar to the real one, and after OR disappears quite strongly and with smoke is smoothly lost grip until the moment the tire is pop. And the grip before pop falls so hard that you feel like you're on snow or ice.. (pic 2) It's just how I feel it, I'm not saying that my opinion is the ultimate truth.

And indeed, in real life, temperature and wear are interconnected, the higher the temperature, the faster the wear, in real life, after 200-250 degree, the rubber of the tire melts. But it seems that in LFS the cord grip is sort of simulated by a low grip after the operating range of the tire and this simplification greatly affects the handling of the car after the operating range. If in LFS tire adds a cord grip like the one in the upper graph (on pic 2), this would correct the situation.

3. Tire stiffness, as i get it, usually in a sports tire, a stiffer tire cord is made in the side parts of the tire too, and normal road tires have a harder rubber composition but a weak metal cord. I'm sure this affects on behavior of tires on the track.
But in terms of stiffness, I don’t see much difference in the LFS, and if you lower the tire pressure to 50 psi, then sports and normal tires behave the same. and go down one level.

In addition, in tires are used different cords, there are tires with diagonal and radial cords. The carcass of diagonal tires consists of several layers of cord, located at an angle to the radius of the wheel. Due to this, the textile cords in adjacent layers cross diagonally with each other. This structure is homogeneous over the entire surface, so the crown and sidewalls of the tire have similar mechanical properties.

With a radial tire design, the cord layers are directed across the center line of the wheel, along the radius. The frame shell is additionally covered with a breaker belt. As a result, the top and sidewalls of the tire differ from each other in their characteristics.

Diagonal cord has high sidewall strength and the better softening of hitting transmitted to the car when driving on roads with small potholes, when moving the seams of the road surface. In radial tires, a rigid breaker reduces tread deformation and the contact patch remains virtually unchanged in shape. Therefore, the volume of the groove does not decrease, and the tread lugs do not slip. But as far as I understand, radial cords are mainly used now in almost all road tires and diagonal for semi slicks. (But i dont sure here)

4. And I had another idea, not quite about physics, but about tires. There are different tire brands in LFS. Why do we need them all if they are all the same except for the logo? Let there be different treadwear for different tire brands. This can be accepted for Normal and Sports tires cuz sport tires arleady have 4 different slicks tires with different treadwear but for some reason the rest tires do not have it.

While that's all I could think of, if anyone else has any comments it would be cool if you shared them.

Not sure what the point of this thread is? The topic of tyre physics and the various improvements it needs/is getting has been done to death. I know there are only so many things to talk about on here but just let Scawen do his thing.

Probably sharing his findings and providing feedback on the current physics

I learned something new, so I appreciate the post. Thanks OP.

More worn tires = better grip, that would be step one to change.

But since it's the same for everyone (and not broken like rF2's insanely ''good'' tire model) I don't mind it actually getting faster as the stint progresses.

1. Behaviour of tyres when going over sharp kerb edges
2. Too high grip while slipping

Quote from k_badam :

Not sure what the point of this thread is? The topic of tyre physics and the various improvements it needs/is getting has been done to death.

Sсawen just starting working on this topic more actively lately. And probably it's important whether the opinion of the players coincides with what is happening in real development or not.

Quote from k_badam :

I know there are only so many things to talk about on here but just let Scawen do his thing.

I'm sure a Scawen knows what to do, but we don't know what a Scawen does about tire physics. Maybe it will be described in the "Development Progress" topic. but I just can't wait And work on the physics of tires was carried out earlier, but there seems to be no specifics about this, except that now all physics will work at 1000 Hz and tire physics too. It sounds good, but as players, we hardly understand how this will affect the handling of the car.

Quote from Dennis93 :

More worn tires = better grip, that would be step one to change.

In reality, it doesn't work quite like that. As I wrote above tire has a "operating range" This is the range of temperature of the tire where is grip with the surface is greatest. Before OR and after OR there is a decline in the grip. And the grip gradually drops until the wear runs out tire to the cord of tire and here the grip falls dramatically until tire pop.

With many racing tires there's some extra grip in first couple of laps, but it wears out quickly...

In karting when doing endurance races on harder compounds, if we did put completely new set before start of the race, it did slip a lot (like +2s per lap) in first few corners until the initial scrub happened, then the tires become extra grippy (-0.5s) but still cold (+2s), in the second lap the temp got almost into window (lap time similar to best lap on used-tires) and usually in third lap the temp was high enough to extract the extra grip and the lap times were about half a sec better than on used tires. This usually lasted for first 20-30 minutes if not pushing too hard on the tires (or only 4-5 laps when pushing in qualify mode, usually degrading the tire by cooking it too hot by the end of the Q session, the qualify tires then usually performed slightly worse than ones which were baked-in more gently), after that period the tires become regular "used tires" which lasted for another 3-5 hours (the performance is stable and lap times improve only because the kart gets lighter with each lap), before they started to be "worn tires" (like +1s per lap) and then after another hour or two the fall of the cliff.

"more worn tires = better grip" IME usually not in karting and formula categories, usually the tire performs best when new, except the very short initial period of "baking it in", which involves initial scrub of it and also depends how the tire should be warmed up and if you did manage to do it properly (if you scrub it + warm it wrong way, you can actually destroy the tire completely in terms of performance, then it will not work as "used tire" even when visually it looks normal, but the compound is already somehow damaged on chemical level and it goes deep into the thread so even scrubbing off another 1-2mm will not save it).

Maybe additional type of tyres?

Since mods have been allowed, maybe karting tyres?

Along with tyres more suited for trucks and buses? Especially as how unrealistic it looks when tyres deform on heavy vehicles while cornering hard.

Quote from sinanju :

how unrealistic it looks when tyres deform on heavy vehicles while cornering hard.

Question is - how realistic was the tyre pressure at that situation? If I'm not mistaken,trucks are running with quite high pressures on the road.

Quote from Aleksandr_124rus :

In reality, it doesn't work quite like that. As I wrote above tire has a "operating range" This is the range of temperature of the tire where is grip with the surface is greatest. Before OR and after OR there is a decline in the grip. And the grip gradually drops until the wear runs out tire to the cord of tire and here the grip falls dramatically until tire pop.

That's how it works in LFS; Hence why I wrote the message.
I'm fairly familiar with tires...

Quote from Dennis93 :

That's how it works in LFS; Hence why I wrote the message.
I'm fairly familiar with tires...

In LFS this is not the case too. The LFS also has operating range, how will you get faster lap time, at 60 tire temp or at 160?

But in imao grip after OR drops so hard that you feel like you're on snow or something until tire pop. In reality, the grip also falls after OR, but not as much. I illustrated how i feel it in the picture.

Quote from Aleksandr_124rus :

In LFS this is not the case too. The LFS also has operating range, how will you get faster lap time, at 60 tire temp or at 160?

But in imao grip after OR drops so hard that you feel like you're on snow or something until tire pop. In reality, the grip also falls after OR, but not as much. I illustrated how i feel it in the picture.

Wear doesn’t always mean more temperature. I didn’t mention temperature once yet infact.

More wear = faster laptimes.
(Not crazy “I am drifting” temperatures)

Quote from Dennis93 :

Wear doesn’t always mean more temperature. I didn’t mention temperature once yet infact.

More wear = faster laptimes.
(Not crazy “I am drifting” temperatures)

Oh i read it like "more warm tires = better grip" in your first comment

Yes, apparently you about the fact that there is still a factor in increasing the tire contact patch due to tire wear.

But there is another factor that on track in places with frequent tire wear, tire particles roll into pellets on the surface of the tire and that worsen the grip. But I don't know if it's worth implementing in LFS.

It still is a bit difficult to put wear and temperature on the same axis, as it implies a 1-to-1 causality. Yes the contact patch changes, but other outside effects also have an impact on temperature but not as much on tyre wear. There is a (strong) correlation for sure, but mixing correlated effects, is not always the best approach for a good model.

Quote from Aleksandr_124rus :

snipped for the sake of everyone and their eyes.

A big change has been 1000hz. That is higher than current, I think a significant amount but I do not remember nor care to dig deep to answer this more in depth.

There was graphical updates as well that were factored into the 1000hz rate. If I am wrong on any part someone can correct me, but these were 2 big parts of whats being updated aside from separately more tyre physics on top of the 1000hz

And I had another idea, there are different tire brands in LFS. Why do we need them all if they are all the same? Let there be different treadwear for different tire brands. This can only be accepted for Normal and Sports tires. ill add it in list of top post.

nah, keep it cosmetic.

Yep, otherwise it’ll just be a meta game

Quote from johneysvk :

nah, keep it cosmetic.

Why?

Quote from Dennis93 :

Yep, otherwise it’ll just be a meta game

And I did not quite get "meta game" take. According to you, having 4 slicks is also "meta game"? Then what does it even mean?
In my opinion, it's just the opposite thing. Right now we just have different skins for tires that do not affect anything, like some cs:go skins. But why? And at the same time, we have slicks with different softness (and wear resistance) of rubber, aka treadwear, I just suggest doing the same for normal and sport tires. Tire physics will change, and all lap records will have to be changed. Only at such moments can you make changes that affect tires. And in semi slicks there is a huge difference in tire grip depending on the treadwear, there is a hard Triangle, Tannus, Zestino that wears out for a very long time and have low grip or soft Westlake, Valino, Achilles, Toyo (R888R or r1r) which wears out quickly but has a large grip, and some middle ground tires. And All these tires play a huge role in real competitions where only semi-slicks are allowed. And same with only road tires.

If we in LFS had more choice it would add more strategy and tactics to circuit racing, and more choice for drift competitions. Because in practice the main thing is more wear and tear, and the competition has more grip. Brands will not go anywhere from LFS, i.e. you do not lose anything, but only acquire a new component in the gameplay of the game. I just don't understand why people don't want this...

Btw most of the mods are saloon and touring cars - 656 mods, (and they are the most downloaded ones) that can only run on sports or normal tires. F1+F.SAE+GT+Formula+Kart (witch is almost all on slicks) is 141 mods, and somereason for most of mods in LFS, we have the smallest selection of tires in terms of their characteristics...

nothing

"Just to say for now that a tyre model may be broken into:

- carcass model
- tread model
- friction model

The carcass model is about how the tyre's structure and pressure affect the output forces depending on the state of the wheel. I can use my simulated tyre carcass (non-realtime) to see how some of these forces vary. I've been making changes to the in-game realtime model to more closely match the simulated tyre.

I don't claim that the simulated tyre is an extremely accurate model of a real tyre but it does give an insight into distortion and deflection and how that changes with tyre proportions and pressure."


Interesting information from the Scawen, but it seems that the cord is not implied in the tire physics at all, or is it somehow included in the carcass model. But on the current version of tires it is difficult to notice.

In my opinion, the lack of cord in the tire is the main problem of the current tire physics, both physically (because there is no difference in the deformation and bending of the tires, between different tires) and in their dynamic parameters such as an unreliable ratio of temperature\wear\grip relative to constant heating by friction. Why does temperature\wear\grip depend on the cord? I may be wrong but as I explained above, with the help of the graph, in my opinion, unreliable decrease in grip relative to the constant heating of the tire is caused by the lack of cords and its parameters of a dramatic drop in grip on the real tire when the layer of rubber ran out. And since there is no cords in LFS we have to simulate its properties through simplifications in the form of not quite correct temperature-grip properties.

It may not be so important for racers because they do not want to drive the tire above the operating temperature range in a first place. But for example for drifters, these parameters are extremely important, and all drifters know about the problem of rapid loss of grip at high tire temperatures in LFS.

I would like to hope that this will be fixed somehow in the new tire physics.

Your cord structure is in auto mechanics terms coined the Carcass of the tire, so the carcass level is the cords

Quote from timdecnodder :

Your cord structure is in auto mechanics terms coined the Carcass of the tire, so the carcass level is the cords

Maybe, but I'm not sure about that, as far as I understand carcass is a more general term, for cord I've heard names Steel-cord or tire belts. But even if this is true, how exactly will this affect the current tire physics?
There no change in grip after layer of rubber that goes to the metal cord, what should be felt. Normal road tires, semi-slicsm, and slicks, all of them have different types of cords, and i do not see any deferense between all tires in stiffness e.g. from side deflections.