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
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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.