this is reactiviating a really old thread but ive noticed something weird about the tyre deformation a few days ago

i was test driving matrixis setup on so and when i spun out i noticed that the car was shaking right after i stopped
at first i though the setup is underdamped but if anything its overdamped and futher investigations showed that its actually the tyres

ive attached a short replay to illustrate what im on about (im using the race s setup btw) ... notice how the rims relative position to the body doesnt change much but the rims potition relative to the ground is changing rather a lot and the whole car is shaking

imho the tyre deformation should be damped a lot more than it currently is

What tyre pressures where you running?

if you *would be* able to steer that fast irl, you would also have some wobble

The cars in LFS sometimes do weird things, haven't that replay but I had a shaky car few times. When starting BL gp hotlap in the GTi for example I let the car go down the hill backwards and it did shake very weirdly when front tires went to full lock in slow speed, and did make a screetch sound allso.

You do have to take into account that in LFS you can do stuff that a real car just couldn't do. You try and pull have the stunts that you can do in LFS, like reversing and flicking into first at full throttle no clutch, would just break stuff in real life. So if you are on the very edge of the perfomance envelope or pushing certain attributes then you won't get a real life equavalent because you just can't do those things in real life.

You probable do get tyre wobble in real life but it would be at such a frequency that you couldn't feel it through the suspension. Or you just lump that wobble into the whole suspension, chassis, tyre, big lardy arse gestalt.

Just a LFS defence.

Quote from Funnybear :

What tyre pressures where you running?

whatever the race_s setup has for pressure

Quote from -V-Max- :

if you *would be* able to steer that fast irl, you would also have some wobble

try kicking against your rims irl ... the car will wobble a little but it will damp itself a lot faster

Quote from Shotglass :

try kicking against your rims irl ... the car will wobble a little but it will damp itself a lot faster

That's why I said 'some', I'm currently working at a volvo garage in brussels. And i noticed today that the S60 wobbles when the driver got out of it, I't wasn't the suspension moving ( id lifted a bit )
It's just a bit heavy in LFS because the model Isn't perfect, we knew that

http://videosift.com/story.php?id=5073

Different but cool tyre deformation

tbh I think that the tyre wobble in LFS is probably overgrown a little because there isn't flex elsewhere in the LFS model, that a real car has. For the model's behaviour to be as realistic as it *is* when driving, but with completely rigid drivetrain etc (which is not true to life), the tyres carry all of the flex modelled in LFS. For example, in real life, the driveshafts twist with torque. In LFS they don't, but the tyre model compensates handsomely for it. The net result is that you can get some slightly unrealistic LOOKING behaviour in a stationary car, such as that shown in the tyres.spr replay.

I havent read this whole thread so i dont know if this had been posted. Also im not really able to post about tyres as i dont know enough. Its a video of drag racing, not track racing so there are differences but it shows how much tyres flew under acceleration and it amazed me and i thought it might show some people who think lfs tyres flew too much how much tyres can flex.
click here for video

Quote from Greboth :

I havent read this whole thread so i dont know if this had been posted. Also im not really able to post about tyres as i dont know enough. Its a video of drag racing, not track racing so there are differences but it shows how much tyres flew under acceleration and it amazed me and i thought it might show some people who think lfs tyres flew too much how much tyres can flex.
click here for video

That's the same video that was posted just above.

Quote from Greboth :

I havent read this whole thread so i dont know if this had been posted.

classic!

Pressure - 3. Abbr. P Physics Force applied uniformly over a surface, measured as force per unit of area.

I'll get me coat

By the time I got to page 4 I had to go back to page one to remember what it was all about....

Quote from DeadWolfBones :

That's the same video that was posted just above.

I said i hadnt read thread

Another thought on why tires have less load in the center than on the edges.

The angle where the sidewall meets the tread is semi-rigid--that is, the tire will deform in such a way as to maintain this angle. If the sidewalls are compressed and as a result bulge outwards, this will create a torque on the edges of the tread, causing the center to lift. See picture for crude rendering of this dynamic.

In all honesty this effect is probably miniscule in real life and not modeled at all in LFS, but it was a thought that occured to me, so I figured I would post it.