Steering wheel shimmy

Has anybody come up with a solution to completely eliminate the wheel shimmy experienced by some cars in AC?
It seems more prevalent in some cars more than others...irregardless of circuit.
I especially notice it in the Praga R1.
It seems to occur most when the steering wheel is perfectly straight and 'unloaded' on very high-speed, non-cambered straights.
It's annoying as heck and takes away from the overall experience.
The rest of the feedback feels great.
 
Thanks for the replies...even the funny ones.
It's on a T500RS.
I finally got it sorted by adjusting the settings a little bit at a time then rechecking feel.
These settings work great and no more shimmy.
 

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Road effects at 65% is extremely high.

The Road Effects and Slip Effects sliders are Amplifiers.

They amplify forces that are already present and being transmitted.

Kerb Effects is the only "canned" effect. Why? Because even if you go over a flat kerb, it will shake/rattle the wheel. Your wheel should already shake/rattle even with this at 0.

You also aren't using any Damper in TM panel. That is part of the problem. AC needs your wheel program to allow Damper. AC uses the damper function. If you set it in TM it's not a constant damper.

I would highly recommend you take a second shot at adjusting these settings.

I would recommend

TM - All at 100 except spring

AC Gain 100

Both Filters - 0

Kerb 0

Road 0

Slip at 30 is fine.

At that point, test one car, and one track, and only test that same combo. Pick one of the cars you had a "shimmy" problem with.

Bring up the pedal app and check for the bar on the right to turn red while driving. If you see it turn red, your FFB is clipping and you need to lower the FFB gain for that specific car (- or + key to change FFB level for car). Better yet, download and use the FFB clipping app.

You need to drive the car and track combo for at least 20-30 minutes to adjust to the new feel. At that point, if you are having a shimmy problem, you should use a LUT for your wheel. There is a thread for it on AC forums. If you don't want to use a LUT you can try using a little bit of Minimum Force-- 1-5%.

Then test the change for another 10 minutes or so. If that got rid of the shimmy good.

I'm just going to quote a post I made on AC forums for further info. Some of it I have already said above.


Allow me to teach you a little about the settings.

Gain is your master, and usually people run it from about 60-100%


Road & Slip

Think of these as amplifiers. With these at 0, you still get Road feedback and Slip feedback. Increasing them amplifies forces already coming to your wheel.

Road is just what you can guess it is: feedback from the road; bumps and cornering forces.

Slip is a vibration from spinning/slipping/sliding tires.


Kerb

This is the only "Canned" effect. It will vibrate the wheel when going over kerbs, but, it will vibrate the wheel even if going over a flat kerb. Understand, your wheel should already vibrate when going over a kerb even with this at 0.


Enhanced Understeer

What you need to know, is that when you turn the wheel too much and get your front tires understeering (slipping), the force on the steering wheel drops. You should feel when you are understeering. Some wheels are quite hard to feel this drop. That's why this option is available. It increases the drop in force in an understeer condition.


What you need to do.

You need to set

Gain 100%

Road to 0


Kerb to 0 or something much lower-- 5 (at least temporarily)

Understeer off

Then, go out and drive.
Do at least 10 to 20 laps, perhaps more, just to adjust to the new feeling.

Then ask, how does it feel? Does it feel too strong? Too light?

Too strong: Reduce gain to 90 and test--the same car and track

Still too strong? Reduce gain to 80 and test--the same car and track

Too light: Do not increase gain past 100%. You will not get a higher force out of the wheel. Gain over 100 only ends up boosting lower and mid forces, and you end up loosing the higher strength forces. You will get FFB Clipping.

If it's too light, or not enough feedback in general, take Road to 1 and test--the same car and track

Still too light? Road to 2 and test.


Right, the most important thing is getting your Gain right. Then if you feel like you are not getting enough feedback from the road you add Road.

Then next most important thing is to go into a turn a little too fast, and turn aggressively so that you get understeer. Do that many times. When you understeer do you feel a drop in force? If not, enable Enhanced Understeer.

Then ask yourself "am I getting some vibration or feeling when tires are slipping/sliding?" You can add Slip if you want more.

Then you can ask, yourself "am I getting enough vibration from the kerbs?" If not, add some Kerb and test.



That is the order you should go in.

1. Gain 100

2. Road 0

3. Understeer off

4. Slip 0

5. Kerb 0


---

1. Tweak Gain. When satisfied:

2. Tweak Road (most PC players do not use road) Even 1% adds a lot. When satisifed

3. Test for understeer, enable and test, disable and test.

4. Tweak slip. When satisfied:

5. Tweak kerb.
 
I had lots of time to 'experiment' today with settings in both AC and the TM control panel.
It turns out the only way to totally get rid of the 'centered wheel shimmy' is to add a value to Spring in TM control panel.
I have mine set to 70 and the wheel now feel great.
 
Hmm...running a T500 and here's my setup.

Thrustmaster Panel:
Strength = 60 (60-65 is the most linear response on this wheel. Above and below gives non linear feedback)
Constant = 100
Periodic = 100
Spring = 0
Damper = 0 (only used at low speed)
Auto-Center = by game

In game:
Gain = 75
Filter = 0
Min Force = 8%
Kerb = 60
Road = 35
Slip = 0
No understeer effect.

The biggest difference for me was also changing the FF_SKIPS_STEPS=0 in the asseto_corsa.ini file. That gives the full feedback rate instead of dumbing it down to around 60Hz i believe.
 
Hmm...running a T500 and here's my setup.

Thrustmaster Panel:
Strength = 60 (60-65 is the most linear response on this wheel. Above and below gives non linear feedback)
Constant = 100
Periodic = 100
Spring = 0
Damper = 0 (only used at low speed)
Auto-Center = by game

In game:
Gain = 75
Filter = 0
Min Force = 8%
Kerb = 60
Road = 35
Slip = 0
No understeer effect.

The biggest difference for me was also changing the FF_SKIPS_STEPS=0 in the asseto_corsa.ini file. That gives the full feedback rate instead of dumbing it down to around 60Hz i believe.

I'd recommend you try a LUT with Min Force at 0.

FF Skip Steps:

Default of 1 is 150hz. 150 updates per second.

0 is same rate as physics engine; 333hz. Some wheels don't work with that and will vibrate.
 

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