Front end chatter?

[ammo]

Hi guys, i'm running the Darkside I-Force at the moment and have a hard time with front end chatter. Is there any common causes for this that i'm missing out?

[serpent]

What front suspension does the car have on it?

[ammo]

It's the standard I-Force front end, looks pretty much the same as associated, etc.

Pink front, green rears, as well as a few assorted compounds i dug out of my tires box. all seems to display more or less the same chatter, just to different extent according to thickness. Hence i suppose it's something to do with the car which i might have overlooked.

[Tom]

What sort of dual-rate do you have?

Going slow, my car has something like an 8 foot turning radius, or thereabouts.  If you have dual-rate so your car has a 3 foot turning radius, all that scrubbing might cause chatter.

I've never had a pan car chatter before, so I'm kind of new at diagnosing it.

[ammo]

I do have a tight turning radius for my local track.
However i notice the chattering starts even at very small inputs when the car carrys some speed. The chattering leads to a lost of grip, resulting in massive understeer.

I will try to reduce the dual rates as low as possible for my track and see how it goes. In the meantime, all suggestions will be good for thoughts as well

[Grinder]

How much slop is in the front end?  Are you runing any toe in/out?

[Tom]

I'm guessing you might need more front grip and less dual rate.

What are you using for traction compound?

What is the track surface?

How is the surface prepaired?

I would not expect toe to influence this behaviour, but who knows.

Maybe the problem is too much rear grip.  Perhaps if you loosen the car up, you can get away with less dual rate.

[Grinder]

Does the tire being out of ballance attribute to chatter?

[Tom]

I'd expect if that were the case, it would be all the time, rather than just when turning.

It'd have to be out pretty far.  I know you can run with a pretty big chunk missing out of a tire and it'll work just fine -- it's when the chunk is part way off and flapping when there's problems.

Chatter would happen at the same frequency regardless of speed, while an out of balance tire would change its effect with speed.  Changing the sidewall height might help with chatter.  What's your tire profile like?

[johnnywhopper]

Along with the size of the front tires being a problem, compound could be as well. Pink on the front is very soft. I've never heard of anyone using pink fronts in on-road. Only oval guys that i know of, and that's only on the left front, never the right. If you've got a tall & soft tire, and the track has a decent amount of grip, the foam could be flexing (or "rolling over") causing the chatter.

john

[ammo]

Slop has been reduced to a minimum.
Very slight toe in if any at all.

Asphalt track, low to medium traction, no traction compound for this car.

Tire is in pretty good shape as far as i can tell. Front camber has been set to achieve a flat wear rate, but i do take a mm off the tires with my truer after a whole day's run.

57mm rear, 54mm front

[Grinder]

Have you tried a harder compound on the front yet?  I'm traction rolling with purple barrels - might have to suck it up and turn the tires down ;)

[Arch]

No slop in king pin assembly? Ive had to put washers between lower spring and E clip before,just to reduce the amout of slop which could cause a chatter.

[Arch]

No slop in king pin assembly? Ive had to put washers between lower spring and E clip before,just to reduce the amout of slop which could cause a chatter.