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Cote Dazur
09-02-2017, 22:55
I find that the effect when braking on the Lotus 49 is too strong. The wheel is getting to hard to turn. What can I do to feel less that effect.

Mahjik
09-02-2017, 23:01
What wheel are you using and what settings are you currently using?

poirqc
09-02-2017, 23:03
I find that the effect when braking on the Lotus 49 is too strong. The wheel is getting to hard to turn. What can I do to feel less that effect.

Turn Fx down. Try around 10 and move it slowly if things feel too weak.

Cote Dazur
09-02-2017, 23:53
Thank you, I will try it and report.

Edit: tried changing FX but it did not change what I wanted to changed.
Changing the swindle from 16 to 22 worked very well.
Thank you all for your support, see you on the track.

konnos
10-02-2017, 08:57
You probably needed to change Fy and Mz too, it wasn't just the braking forces that were strong, if Fx didn't make too much of a difference.

Cote Dazur
10-02-2017, 09:36
It was not so much that it was strong, as hard to fight, but that the effect was too strong, as in unnatural, as in a car the wheel does not feel like that when you brake.
At 22, it feels natural. I checked the value in other formula, they all have 26 as a value and they feel alright, not sure why the Lotus 49 was set at 16.
Lowering Fx did make a difference, but did not correct the feeling when braking that I was trying to fix. I prefer the Fx the way they were.
What would changing, assuming lowering, Fy and Mz on the Lotus 49 achieve in your view?

konnos
10-02-2017, 14:57
Well you are describing things that have to do with lateral grip, that's why I assumed Fy was too strong. Fy does contribute to the braking sensation if you are turning at the same time. And you now said it's hard to steer, so it's safe to assume Fy is too high. I also suggested to lower Mz, or just try and see, because you now lowered Fy and that may leave Mz feeling stronger than before.

MarleyMoo
10-02-2017, 19:06
Might I offer another viewpoint: It's caused by the combination of low caster and flexible tyre.

So when you brake, the contact patch gets pulled rearwards w.r.t. the spindle. This increases the pneumatic trail. Since the total trail is the mechanical trail (proportional to caster) + pneumatic trail, and the total aligning torque is proportional to total trail, if the caster angle is low then the effect of variable pneumatic trail is very apparent. Indeed the Lotus 49 has a low caster at 3 degrees, which is less than modern formulas. On top of this of course there's forward weight transfer that also increases steering effort.

Maybe try maxing out the caster angle and lowering overall ffb scale accordingly. This will potentially reduce the effect of the variable trail on steering effort under braking.

hkraft300
10-02-2017, 23:48
Maybe try maxing out the caster angle and lowering overall ffb scale accordingly. This will potentially reduce the effect of the variable trail on steering effort under braking.

Increased caster results in increased steering effort anyway, no? Because of self-aligning...?
I like a "heavy" (note G29 is piss weak) wheel and strong self-aligning so I generally bump up caster angle to max or ~9-10 degrees where available.

MarleyMoo
11-02-2017, 00:17
Increased caster results in increased steering effort anyway, no? Because of self-aligning...?
I like a "heavy" (note G29 is piss weak) wheel and strong self-aligning so I generally bump up caster angle to max or ~9-10 degrees where available.

Yes. By increasing caster you add in a set amount of trail, the mechanical trail, that is constant and not affected by braking. This will drown out the variable effect of the pneumatic trail that *is* affected by braking.

hkraft300
11-02-2017, 06:36
Ahh I see!