Gents,
I've just read all your comments with avvid interest. I too have a 530d M Sport Auto LCI on the 135 MSport (18" RFT) RIMS. Whislt the techy answer may have something to do with it I think my final conclusion out of the problems that I have had is that the car is just really sensitive to geometry.
I battled with BMW from purchase in July 07 to Dec 08 trying to get my car sorted ( overall slight pull right, and more nervousness than my heart could deal with above 65mph. If I took my eyes off the road the car would wander off the direction set). The final conclusion was that after 3 KDS adjustments, and a independant Hunter Hawkeye assessment, the E60 is very very sensitive to settings and tyres.
Here's the total of my learned experience.
Setting the car up takes a sensitive hand, and absolutly no bull from technicians that say that when a setting is +/- 0.02 out on toe it wont matter. Believe me with these cars .. it does and I've experienced it first hand. Someone is going to also shout me down and say that these differences are so small that you cannot feel them. I'm going to tell you that in my experience with Porsche, and BMW ....you can. Some poeple are very spacially aware, and those poeple can easily feel the differences.
So to the problem described.....
I look at your original settings and see a car that would appear to have a thrust angle to the right of the car , overall front toe bias just to the left, and overall rear toe bias to the right .... this would appear to be a mixed bag that would be roughly similar to the settings prevalent on my car in the beginning.
The adjusted car would appear to still have a thrust angle to the right, albeit 0.01 less, overall front toe bias significantly left, and overall rear toe bias to the right. It's an improvement.... but not going to cure the twitchiness.... btw .. I think what happens in the wind just makes something you can't feel when not windy noticeable.
My advice. Your car is doing subtle things to try and twist about it's central axis. The thrust angle will make the rear end skew out to the right. The front toe will make the front end skew to the left, and the rear toe will also try and push the rear out to the right.
First things first. Have the car measured on a Hunter Hawkeye independently to "measure" the current settings. Do not let them use the ride height measurement tools on the hunter if they have them. Have the car weighted up appropriately and have a full tank of fuel.
Take your results and compare. They will be different. Look at the overall picture and relative trend. If the picture overall looks the same, then go back to your dealer with the results, and get them to agree to re-KDS it. If they won't recheck get them to refer it to the area technical manger.
Then dig your heels in and ask your dealership to re KDS and a) for you to be present, for the workshop manager to be present, and c ) have each part explained to you by the technician. Establish when both machines were last calibrated (dealer + independant) , and what software levels each is using.
Every time the technician explains why he's making an assumption about not having to do something, get him to explain why. Make sure that when they set the car up, they make all the adjustments they can, and that the tech makes sure the settings are as per the target , not near, or close but bang on. The techs are going to whine and say it's impossible. I've seen a tech do it and do it right. He got the settings bang on, and when they went off having adjusted another wheel, he bounced the car let it resettle and went back and readjusted, again and again and again. It cured my problems on my final KDS. They didn't like it.. but I stayed until I was hapy with the final numbers. toe needs to be more not less than the target if anything.
(btw The more front toe you add, the more stable the steering will feel, and the greater the centre feel. The more rear toe, the more stable in a straight line, but on cornering you get a sharper bite / turn in from the rear. makes it feel more nimble.
So for example if they use the ride height sensors, ask why many dealers have stopped using them, and would they be better off just weighting the car appropriately? My dealership stopped using it in favour of just weighting the car with a full tank of petrol + the advisory weights for occupants. The ride heigth sensors just add more complexity by adjusting the angles for given heights of the wheels from the chassis. I think in practice, this just buggers everything up. (IMHO).
So get the thrust angles right on the rear, along with the toe nice and even on the rear, and then get the front sorted. even toe = no pulling bias or twisting.
Then get your tyres sorted asap because it won't feel right until you get the wear even. CHANGE the LOT !... It's a lot cheaper than RIMS !!!!
In comment of your tyre pressures - they have been off. Change the garage where you inflate for somewhere more reliable. Inflate when it gets cold outside. You need to watch this. Your fronts are underinflated indicated by the greater tread in the centre. The uneven wear pattern in the fronts is most likely caused entirely by this. The new geometry settings will only make this feel worse.
Your rears have also been slightly off pressure- probably very slightly overinflated for your driving/loading. The left rear inner edge wear will be caused by the drag of the overall right hand toe. Otherwise. The new settings will reduce the wear. BUT the car is going to feel like it's all over the place with uneven wear.
You say you've been running stock pressures but my tyre panel suggests for the 19" that you should have 2.3 Front and 2.6 rear. The front would be consistent with my advice, however I think you need to take 0.1 out of the rear given the numbers.. ( if you do fast/heavy/long distance take the pressure out. If you do light/slow/short journeys put it in ).
My car when set up by the tech to the target settings, and + a little more front toe, completely rid the twitchyness. It's now got to be really windy ! and thats only to be expected.
The thing you do have to realise is that a combination of geometry and tyre wear are now placing funny forces all over the place. This chassis is sensitive to it, and it wont feel right until the geometry is square (toes and cambers are ON SPEC) ... My replacement cars have been on both 172's and 135M's . The 172's felt better overall than 135 RFT's IMHO.... and I'm not a great fan of ultra low profiles
good luck !
