high winds
#11
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From: So Cal, USA
My Ride: 545iSMGSilver GrayAuburn Dakota LeatherLogic 7 Premium SoundSports Package
Originally Posted by subterFUSE' date='Apr 3 2005, 05:47 PM
AS changes the ratio dependent on speed, but not on small speed icrements but large ones.? As long as you are driving over something like 40 or 50 mph, the ratio is at 18:1
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#12
Had a really tough time with the wind this weekend. Wife and I were taking a couple hour trip, and I was going nuts with the wind the whole time. We were on some straight and open country roads going at a nice 85+ mph clip, and the wind was kicking up probably about 25-30 mph gusts. It was very, very difficult to keep the car from moving sideways 6-9" every few seconds as the gusts hit. After about 30 minutes of fighting it, I had to drop down to about 60 mph to control the car safely in the wind. Even at 60 mph, it was still unpleasant to drive.
I don't know if it's the AS or something else, but I've been on the same road, in similar wind conditions with my e39 in the past, and did not have anything close to the problems I had with the e60 on Friday.
I don't know if it's the AS or something else, but I've been on the same road, in similar wind conditions with my e39 in the past, and did not have anything close to the problems I had with the e60 on Friday.
#14
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From: New Orleans, LA USA
My Ride: E90 M3
Model Year: 2011
Originally Posted by EBMCS03' date='Apr 3 2005, 11:06 PM
[quote name='subterFUSE' date='Apr 3 2005, 05:47 PM']AS changes the ratio dependent on speed, but not on small speed icrements but large ones.? As long as you are driving over something like 40 or 50 mph, the ratio is at 18:1
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[/quote]The steering ratio may be the same past a certain speed, but the AS does have the ability to compensate for steering movements. The non-AS cars do not have this ability, all steering movements are up to the driver. As Ultra points out this was discussed a long time ago. The AS will sense the car steering change due to the wind and compensate, as will the driver, perhaps causing too much movement in the steering undert windy conditions. I don't know, I just remember the earlier discussion. Very well could be the tires as well, because I am using the 17" non-sport tires on my car and I don't have any problems in windy conditions...
#15
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From: Winter Park, FL
My Ride: 2005 545i (SMG)
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Active Steering will make correction to the car's intended direction, if the wind is blowing into the car. Your brain tell you to make the correction yourself, but you should just let the Active Steering do the correction. Otherwise, you'll be fighting the Active Steering.
Are you 100% certain on that? I have read a good bit about the Active Steering technology, and from what I read it is simply a changing steering ratio from 10:1 to 18:1. It says nothing about course correction.
Course Correction may be due to DTC or something like that. For example, I hit a puddle on the highway with my right side recently, and I felt the car hydroplane, but the DTC corrected the car right away.
I seriously do not think Active Steering has anything to do with the high wind issue, but more likely is DTC.
#16
Originally Posted by subterFUSE' date='Apr 4 2005, 08:36 AM
Active Steering will make correction to the car's intended direction, if the wind is blowing into the car. Your brain tell you to make the correction yourself, but you should just let the Active Steering do the correction. Otherwise, you'll be fighting the Active Steering.
Are you 100% certain on that? I have read a good bit about the Active Steering technology, and from what I read it is simply a changing steering ratio from 10:1 to 18:1. It says nothing about course correction.
Course Correction may be due to DTC or something like that. For example, I hit a puddle on the highway with my right side recently, and I felt the car hydroplane, but the DTC corrected the car right away.
I seriously do not think Active Steering has anything to do with the high wind issue, but more likely is DTC.
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From C&D - http://www.caranddriver.com/article.asp?se...article_id=7573
"At high speeds, the 5-series was no more stable than previous BMWs, which have exemplary stability. In fact, we've driven two Sport-package-equipped 530i's, and both exhibited some bump steer, despite a slow steering ratio (18.0:1) at high speeds. Creepily, the active steering can automatically throw in a little countersteer (yes, without your command) should a strong crosswind begin nudging the car off your intended path. On a gusty highway drive, though, 20-mph crosswinds had their way with the 530i more than we expected. Our collective brain was never able to accurately anticipate how much turning would result from a given amount of steering angle. Ultimately, the steering system's unpredictability makes it feel artificial and a bit distant. Also, we had to make more steering corrections through a corner than we remember making in previous 5s."
http://www.designnews.com/article/CA330639.html
"While the Active Steering changes steering ratio when its motor rotates the gearbox ring gear, the effect is to change the front axle steering angle during a turn as well. BMW engineers took advantage of this characteristic to introduce limited steering inputs in emergency maneuvers, such as a series of sharp turns to avoid an obstacle. The Active Steering controller applies up to 2.5? of front wheel angle countersteering to avoid a skid without the car's Dynamic Stability Control initiating selective wheel braking with its sometimes disconcerting noise and deceleration. "The closed-loop Active Steering controller compares the driver's steering wheel angle input with the vehicle's output (lateral acceleration and yaw rate). The amount of countersteer provided depends on the difference between the driver's input and vehicle reaction," Koehn says. "
http://www.bmwnation.com/articles/e6..._depth_03.html
http://www.autoweb.com.au/cms/A_101143/newsarticle.html
Active Steering is also able to automatically correct any oversteer by means of counter steering, thus supplementing the car?s DSC Dynamic Stability Control smoothly, comfortably, and without the driver even noticing.
#17
I can feel AS (or DSC or DTC or all of them, who knows) making corrections in the wind. Whether it's AS, DTC or DSC isn't the point - the point is that it is not an experience we've had in any other car - having directional corrections made for us. It's different, and takes a bit of getting used to.
I think the consensus is that it's AS, since the folks complaining all seem to have AS, and people without it are saying that the car's not that bad in the wind.
You will get used to it over time, but it takes a while, and it makes switching cars tougher, as the 5 trains you not to react to the wind, while you may still need to in the wife's SUV.
I think the consensus is that it's AS, since the folks complaining all seem to have AS, and people without it are saying that the car's not that bad in the wind.
You will get used to it over time, but it takes a while, and it makes switching cars tougher, as the 5 trains you not to react to the wind, while you may still need to in the wife's SUV.
#18
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From: Toronto, Canada
My Ride: 2006 BMW M5, Silverstone with black extended leather, brushed aluminium trim, Nav Pro, Logic 7, PDC, 35 % tint.
I don't have AS and I also noticed that during high winds on the highway it affected the car more than my last 5 series. I think it may be that the car is lighter due mainly to the use of aluminum for the frame, especially the front end, instead of steel.