Help me understand something...

[racinjoe013]

I've struggled with this for just about every sim i've ever played and have never been able to find a good explanation anywhere on the net.

So I take the BMW GT3 out on to Nordschleife with the stock setup. Right away I can tell that it's too bouncy and the car loses grip with the road over the slightest bump and gets out of shape. Here's where I get confused. I'm not sure what to change to get rid of that condition. Should I stiffen or soften the spring rate to absorb impacts better? And this is the one that really gets me, which way should I adjust the bump and rebound? I've read numerous setup articles about bump and rebound, but they only describe what they are. I have yet to find an article that explains how raising and\or lowering bump and rebound effects handling and car reaction so all I end up doing is changing things with no knowledge of what's going to happen.

Any advice or link to a guide would be greatly appreciated. Thanks.

 

[Foskifo]

Hello, I have a good guide made for the old GTR game, enjoy !

 

[racinjoe013]

Thank you. Looking forward to reading this later today to see if I can learn anything.

 

[Foskifo]

It will definitely help you as it explains what parameters to tweak to correct type of effects you can encounter on track

Please give a feedback if it suits you

 

[racinjoe013]

Haven't forgotten about the feedback request. Just haven't found time to go through it all yet.

EDIT: Had some time to try and look it over and try some things on my Nords setup to get rid of the bounciness, but have a question. In the guide it says to harden the bump\rebound to try and eliminate this problem, but i'm confused in the game as too which way to go to harden them. Can't wrap my head around the settings. If I hit the plus sign, the setting number gets lower which is totally opposite to every other sim I play. Hitting the plus raises the value. So in rF2, which way hardens the bump\rebound? Thanks

 

[=Fieldzy=]

So if you press the + to its total you will see it is hard ,Press the - to the total it will show soft for the BMW GT3. You can do this for any car to show what is hard and what is soft.

 

[Jose Angel Valera]

Haven't forgotten about the feedback request. Just haven't found time to go through it all yet.

EDIT: Had some time to try and look it over and try some things on my Nords setup to get rid of the bounciness, but have a question. In the guide it says to harden the bump\rebound to try and eliminate this problem, but i'm confused in the game as too which way to go to harden them. Can't wrap my head around the settings. If I hit the plus sign, the setting number gets lower which is totally opposite to every other sim I play. Hitting the plus raises the value. So in rF2, which way hardens the bump\rebound? Thanks

+ is more
- is less
I know is weird but some GT3s use Ohlins dampers. Ohlins has an inverted system or something like that on their dampers, thats why you see it inverted on the screen.

Regarding the bouncing you can stiffen + the rebound setting to stabilize the chassis when the car hits a bump.

Basically the BUMP setting controls the movement of the wheels and the REBOUND controls the movement of the chassis.

So if the chassis is jumping all around you can add + Rebound to help controlling the mass of the chassis. But be careful add + REBOUND in small increments as reduce tire compliance to the road.

Hope it helps.

 

[Darren George]

I'm an ex F1 shock absorber designer, so maybe I can help.

In a lot of rFactor 2 mods you will have 4 way dampers so you can tune what they refer to as Slow Bump, Fast Bump, Slow Rebound and Fast Rebound. So as to be clear, Slow means Slow Speed, and Fast means Fast Speed. That Speed is not the car speeds but the speed of the dampers shaft, or how quickly the wheel moves up and down if you want to think of it that way.

Very generally, your feel of the cars transient behaviours, so turn in, braking, power on, etc will all be in the slow speed range. So if you are having issues with a cars turn in response you'd be wanting to adjust the slow speed value (as said above + is harder - softer). High speed is when the car is crashing over kerbs or landing after a jump etc. Now for problem 1 (same in real cars), slow speed damping effects high speed damping, because you have to move through the slow speed range in order to get to the high speed range. So if you are happy with how it rides kerbs, and then you raise the slow speed, you may need to soften the high speed to get the kerb ride nice again. Just something to think about if you start getting lost (dampers get people lost).

Now to your specific issue. The answer is not overly straight forward because you have a suspension system of interacting parts it can get a bit confusing and you need to try to isolate some stuff to see where the issue might be. For example with your issue, at this moment in time you don't know if the suspension (either springs or dampers of both) is too stiff with respect to the tyres, and therefor you are bouncing around on the practically undamped tyres, or if the suspension is too soft and too lightly damped. So it would be good to take a look at your data. If you haven't installed the data logging plugin and turned on all the channels then I'd highly recommend doing so. I have a video on how to do that on my YouTube channel.

By looking at your suspension displacements you should be able to see if you have lots of lightly damped oscillations. If you do then you can tweek the damping to have an effect. If however you are not seeing displacements in the range that you would think given that you are describing quite a bad sensation, then it might be that they tyres are doing all the bouncing, and you might then want to try drastically softening the suspension and damping and seeing how that feels.

I'll do another video in the next few days about what to look for in the data for suspension and damping. I'll try and explain a little bit more about bump and rebound too.

Hope that helps give you some direction.

 

[Jose Angel Valera]

I'm an ex F1 shock absorber designer, so maybe I can help.

In a lot of rFactor 2 mods you will have 4 way dampers so you can tune what they refer to as Slow Bump, Fast Bump, Slow Rebound and Fast Rebound. So as to be clear, Slow means Slow Speed, and Fast means Fast Speed. That Speed is not the car speeds but the speed of the dampers shaft, or how quickly the wheel moves up and down if you want to think of it that way.

Very generally, your feel of the cars transient behaviours, so turn in, braking, power on, etc will all be in the slow speed range. So if you are having issues with a cars turn in response you'd be wanting to adjust the slow speed value (as said above + is harder - softer). High speed is when the car is crashing over kerbs or landing after a jump etc. Now for problem 1 (same in real cars), slow speed damping effects high speed damping, because you have to move through the slow speed range in order to get to the high speed range. So if you are happy with how it rides kerbs, and then you raise the slow speed, you may need to soften the high speed to get the kerb ride nice again. Just something to think about if you start getting lost (dampers get people lost).

Now to your specific issue. The answer is not overly straight forward because you have a suspension system of interacting parts it can get a bit confusing and you need to try to isolate some stuff to see where the issue might be. For example with your issue, at this moment in time you don't know if the suspension (either springs or dampers of both) is too stiff with respect to the tyres, and therefor you are bouncing around on the practically undamped tyres, or if the suspension is too soft and too lightly damped. So it would be good to take a look at your data. If you haven't installed the data logging plugin and turned on all the channels then I'd highly recommend doing so. I have a video on how to do that on my YouTube channel.

By looking at your suspension displacements you should be able to see if you have lots of lightly damped oscillations. If you do then you can tweek the damping to have an effect. If however you are not seeing displacements in the range that you would think given that you are describing quite a bad sensation, then it might be that they tyres are doing all the bouncing, and you might then want to try drastically softening the suspension and damping and seeing how that feels.

I'll do another video in the next few days about what to look for in the data for suspension and damping. I'll try and explain a little bit more about bump and rebound too.

Hope that helps give you some direction.

Very helpful, thank you mate.

 

[Pappa_G_27]

I'll do another video in the next few days about what to look for in the data for suspension and damping. I'll try and explain a little bit more about bump and rebound too.

I'd love a video to explain a bit more on what to look for in the data. I have a rough idea, but sometimes i still get confused as to what would change what on the data. The data doesn't always correlate with the setup change i have made that i'd expect. Really would love to be able to interpret it a bit better.