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      05-31-2007, 10:35 PM   #1
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Question for the Suspension Guru's

I have my Koni Yellows adjusted to 1 turn from soft, both front and rear. Ive noticed as Ive been driving that the rear feels stiffer. It thumps more over some ridges than the front does.

I then realized that the rears only turn 5 half turns, were as the fronts turn 6 half turns. Thus the fronts are set at 33% of stiffness where as the rears are set at 40% of stiffness.

Now here is the question. What type of drive characteristic does the stiffer rear settings induce?

Im thinking understeer, but Id like to hear from the pro's.
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      05-31-2007, 11:22 PM   #2
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not enough for you to notice on daily driving....

but if you push hard, you may experience extra understeer.... besides that, nothing else... your not tracking the car so you will be fine, easiest thing to do to eaven it out, is obviously to adjust the fronts to be more like the rears....


i still have a hard time adjusting my koni yellow rears.... maybe you can help me with that...
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      05-31-2007, 11:44 PM   #3
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Understeer, thats what I thought, thanks man.

Too bad youre not closer, we could work on them together. At this point, I have to pay someone to adjust them, and Im not even sure they are getting adjusted right.
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      05-31-2007, 11:57 PM   #4
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no problem....

i have a hard time adjusting the rears, i just cant figure out which way to turn the pin at the top.... i tried both ways and i cant really say one is THAT much stiffer than the other....
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      06-01-2007, 12:45 AM   #5
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Quote:
Originally Posted by montreal_bimmer View Post
no problem....

i have a hard time adjusting the rears, i just cant figure out which way to turn the pin at the top.... i tried both ways and i cant really say one is THAT much stiffer than the other....

Anthony,

You can't adjust the rears via the top of the dampers. The rears are only adjustable internally, i.e. when the shocks are off of the car.

Chris,

When you stiffen up the rears, you get oversteer, not understeer. Soften up the rears and they stick better, thus harder to break loose.

Danny
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      06-01-2007, 01:14 AM   #6
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Quote:
Originally Posted by HRC View Post
When you stiffen up the rears, you get oversteer, not understeer. Soften up the rears and they stick better, thus harder to break loose.
+1
Oversteer
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      06-01-2007, 02:06 AM   #7
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Quote:
Originally Posted by Fraggy View Post
At this point, I have to pay someone to adjust them, and Im not even sure they are getting adjusted right.
Errr, that's fustrating. Koni website has clear instructions on how to adjust the rears. It must be annoying not to be able to watch the turns being made on the rear shocks.

Wondering if you could ask to step in and do the adjustments yourself?

What is everyone else doing about their rear adjustments?

How do Koni yellow feel full soft? Maybe just run the rears full soft. Hopefully not hard to mess that up.
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      06-01-2007, 10:07 AM   #8
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Quote:
Originally Posted by HRC View Post
Anthony,

You can't adjust the rears via the top of the dampers. The rears are only adjustable internally, i.e. when the shocks are off of the car.

Chris,

When you stiffen up the rears, you get oversteer, not understeer. Soften up the rears and they stick better, thus harder to break loose.

Danny
thanks.... yes and it is oversteer.... i get mixed up with them sometimes....

anyway, i know the rear shocks have to be removed to adjust them, and its no problem removing the rear shocks, takes me about 15 minutes to take off one side.... but i follow the instructions on the koni website, so compress the shock all they way, then turn the pin at the top, but on the website, it says to turn counter clockwise to stiffen up the shock, but on the tool i got with the shocks to adjust them, it shows that stiffer must be acheived by turning clockwise....

im so confused....lol
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      06-01-2007, 11:49 AM   #9
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Quote:
Originally Posted by Fraggy View Post
I have my Koni Yellows adjusted to 1 turn from soft, both front and rear. Ive noticed as Ive been driving that the rear feels stiffer. It thumps more over some ridges than the front does.

I then realized that the rears only turn 5 half turns, were as the fronts turn 6 half turns. Thus the fronts are set at 33% of stiffness where as the rears are set at 40% of stiffness.

Now here is the question. What type of drive characteristic does the stiffer rear settings induce?

Im thinking understeer, but Id like to hear from the pro's.
Here is how to correct understeer and oversteer:

http://www.rogerkraustires.com/TechS...verunder.shtml
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      06-01-2007, 12:10 PM   #10
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Quote:
Originally Posted by montreal_bimmer View Post
thanks.... yes and it is oversteer.... i get mixed up with them sometimes....

anyway, i know the rear shocks have to be removed to adjust them, and its no problem removing the rear shocks, takes me about 15 minutes to take off one side.... but i follow the instructions on the koni website, so compress the shock all they way, then turn the pin at the top, but on the website, it says to turn counter clockwise to stiffen up the shock, but on the tool i got with the shocks to adjust them, it shows that stiffer must be acheived by turning clockwise....

im so confused....lol
The website even shows them in a different position, if that matters. The materials that came with the shock show them to be held horizontally, and the website says to hold them vertically. Does it matter?
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      06-01-2007, 12:12 PM   #11
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Quote:
Originally Posted by S4to335 View Post
Here is how to correct understeer and oversteer:

http://www.rogerkraustires.com/TechS...verunder.shtml
Thanks!
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      06-01-2007, 12:14 PM   #12
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Quote:
Originally Posted by kevE90zsp View Post
Errr, that's fustrating. Koni website has clear instructions on how to adjust the rears. It must be annoying not to be able to watch the turns being made on the rear shocks.

Wondering if you could ask to step in and do the adjustments yourself?

What is everyone else doing about their rear adjustments?

How do Koni yellow feel full soft? Maybe just run the rears full soft. Hopefully not hard to mess that up.
They are way too soft on soft setting. I did watch them do it, but they didnt seem to really know what they were doing, it was their first time. But they worked real hard on it though.
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      06-01-2007, 08:05 PM   #13
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Quote:
Originally Posted by Fraggy View Post
They are way too soft on soft setting. I did watch them do it, but they didnt seem to really know what they were doing, it was their first time. But they worked real hard on it though.
That's the best we all could hope for I guess. They will become more familiar with the system each time you take your car in for rear adjustment. Hopefully you get it the way you want by second-third time.
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      06-01-2007, 10:08 PM   #14
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Quote:
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That's the best we all could hope for I guess. They will become more familiar with the system each time you take your car in for rear adjustment. Hopefully you get it the way you want by second-third time.
Ouch, and 300 bucks later
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      06-01-2007, 10:08 PM   #15
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Too bad ///Matt isnt in San Diego.
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      06-06-2007, 03:10 PM   #16
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Quote:
Originally Posted by HRC View Post
Chris,

When you stiffen up the rears, you get oversteer, not understeer. Soften up the rears and they stick better, thus harder to break loose.

Danny
Will the DTC/DSC help to prevent them breaking loose?
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      06-18-2007, 09:44 AM   #17
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Quote:
Originally Posted by Fraggy View Post
Will the DTC/DSC help to prevent them breaking loose?

Yes, any traction control device will prevent wheel spin. To throttle steer the car, turn all traction controls off.

Danny
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      11-30-2007, 12:37 AM   #18
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Quote:
Originally Posted by Fraggy View Post
The website even shows them in a different position, if that matters. The materials that came with the shock show them to be held horizontally, and the website says to hold them vertically. Does it matter?
adjusting the rear is not hard at all, i've been messing around with the adjustment lately and found discovered an easier way of removing the shocks, meaning removing the control arm bolt is unnecesarry. all you need to do is remove the top and bottom nuts of the shocks and compress(pull down) the shaft and the shock will come off the control arm. horizontal/vertical does not matter. i do it vertically coz i dont have a table mounted clamps. so i used a piece of rubber to cover the shaft threads by clamping it with a vice-grip and setting it on the floor while stepping on the vice grip. push all the way down and turn it slightly until you feel it bite then turn according to the specs. 1 turn/click = 180 degree.
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      11-30-2007, 04:26 AM   #19
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It's oversteer as already mentioned. You want to set up your car for a mild understeer actually , you'll notice thats how BMW sets up their suspension. The reason for that in suspension it lets you know when the car is going to resist before as natural in a rwd car you are going to get your oversteer - baically helps you feel out and react to your cars actions.

AWD guys want less understeer as possible, hardest thing to do is get an awd to oversteer(besides yanking on that hand break or having a yaw control) so they have different setting tendencies. My 2 cents on the subject
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