I just put my stock wheels with brand new S02s all around back on and had the car aligned to U.K. specs. The alignment tech could not get the driver's side front caster all the way to 6 deg. 45' - just to 6 deg. 30'

Can this be causing the shaking I'm experiencing at speeds above about 65 mph (the shaking is intermittent - progressively gets stronger over about 1-2 seconds, decays over the same time frame, goes away for about 2 seconds, then starts the cycle all over again)?

The alignment tech (11 years experience) said "Are you trying to make this a race car?" when I handed him the specs I got off S2KI. He said that he expected the car to shake considerably with this amount of caster.

I would very much appreciate any input you may have.

Thanks.

Matt

 

i have UK alignment on my car. There is definately no intermittent shake.

 

It is not the alignment, more likely the tires. If they are in balance and properly mounted you may have one defective tire.

 

First of all, cdelena is right. Get those tires/wheels balanced.

But, most importantly, caster for UK specifications is 6 degrees. Flat. Its not 6 30', and certainly not 6 45'.

Edit: I obviously mixed up the workshop and UK specifications, sorry about that.

 

This shows the UK-spec is 6'45" caster for the front....

And I agree with cdelena that an intermittent shake is most likely caused by unbalanced tires.

The S-02's have an arrow on the sidewall showing rotation, they all are mounted correctly?
Also, check tire pressure on all four.

I'm using the UK-spec allignment without any intermittent shake.

 

 

So now that I've accepted my mistake and apologized, onto a question. Isn't 2 degree rear camber a bit too much? Wouldn't you need track conditions to utilize that camber?

Can those specifications be used on AP2s?

 

Vibrations will never be the result of a bad alignment. At the speeds you described, it sounds like a balancing issue.

 

If this is true, the tire store (Discount) techs are idiots, as they've had two chances to balance the tires and the problem is still there (I've checked air pressure, directional arrows, etc.).

Maybe I should just go get them balanced somewhere else.

Edit:

I just looked at the specs from the alignment. They are:

Front Camber: L:-0.9 deg; R:-0.9 deg
Front Caster: L: 6.4 deg; R: 6.8 deg
Front Toe: L: -0.01 deg; R: 0.00 deg

Rear Camber: L: -2.0 deg; R: -2.0 deg
Rear Toe: L: 0.03 deg; R: 0.02 deg

Do these results look okay to those of you who understand them?

 

Well unfortunatley I have this same exact problem and can not figure it out. Check this post It has alot of people who have this same exact problem and everything they did to try and fix it.

And yes everyone says balancing balancing balancing, but you can only balance tires so many times there is obviously something else which is very hard to track down. So good luck and keep me posted.
https://www.s2ki.com/forums/index.php?showt...0&#entry8449969