I don't like electric assist stearing.

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I have had my Z4 since November and normally drive it on weekends. My everyday vehicle is a 4Runner.
I can see where if one drove the Z every day one could get used to the
understeer of the electrical assist. But it feels sluggish to me and I think could contribute to accidents. That almost happened to me. I came into a corner a little hot, I turned the wheel and then had to quickly compensate for the understeer. I hate to say it but the 4Runner is more responsive.
I don't know why they had to mess with something that worked. Maybe adding tower braces will help.
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Did you try increasing the front tire pressures as I suggested to you last week? For the 3.0 stock cold pressures are 33F, 36R and for the 2.5 they are 30F, 33R. IIRC, there haven't been any understeer complaints on the Roadfly Z4 board.
Tom K.
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On Sun, 11 Mar 2007 14:45:27 -0400, "Tom K."

    That was my fix as well. I've also heard of people increasing the negative camber or adding a strut brace.     epbrown
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I did and it helped a little. I am thinking the tower brace as well getting rid of the ride flat tires may help. But I am not going to swap tires just yet.
And I would not expect too many complaints on this board.
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grinder wrote:

I don't see how adding braces would change anything. Sell the car and buy one you like to drive. Oh, and test drive the next one.
--
-Fred W

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Thanks for the help homer.
Oh, I did. But it is difficult to get a real good feel for a car in just a 15 minute ride and other features were comparable to the competition.
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Braces will reduce flex on hard corners thereby keeping more tire on the road and improving cornering performance.
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grinder wrote:

Undoubtedly true. But that was not your initial complaint. You said you did not care for the feel of the electric assist. Reducing or eliminating chassis flex will help reduce understeer, but not really change the feeling of the electric assist.
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I guess I should have been more explicity. The "feeling" I was describing was understeer. Another description might be sluggish (not unresponsive but not quick). I realize it is better than found on a SLK but is not as good as a Boxster or Miata.
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grinder wrote:

I have a feeling that you are misunderstanding and misusing the term "understeer", which may be leading to a lot of the confusing answers that you are getting.
Understeer is the condition that occurs during cornering where the car wants to "push out" the front end, pointing the car toward the outside of the corner. In essence you are "under steering" the corner. Oversteer is exactly the opposite, where the rear end kicks out and points the car toward the inside of the corner.
These have mostly to do with chassis balance, weight distribution and dynamic weight transfer during cornering. It has very little to do with the amount of steering "power assist" or the steering ratio.
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From a review:
"In fact, if there's a fault to be found with the Z4's handling, it's the opposite: The rear sticks longer than necessary (read "understeer")."
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grinder wrote:

Correct, just as I said above. And this has zero to do with the electric steering assist.
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You're right - I was wrong. Unfortunately unlike many members in this group I recognized a flaw in the Z4's handling and attributed it to the electrical assist steering. I should have attributed to the design of the suspension.
In any case. The understeer is still present regardless of the source.
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From another review (this happened to me):
Out on the fabulous Jerez circuit, the dull steering doesn't really dent your progress, but the Z4 M's quite pronounced understeer does. If you misjudge your entry speed it's not easy to rein it in and exit the corner cleanly. Through the slower corners particularly you have to work hard to keep it neat and tidy.
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Yes but you say the problem is the wheels don't turn as quickly as you want them to, not that the front end was losing traction.
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I never said the front end was losing traction. I described understeer ("That almost happened to me. I came into a corner a little hot, I turned the wheel and then had to quickly compensate for the understeer.") . Now I think the electric assist steering is not the problem. The problem is the way the car is set up.
From another review:
"Basically, it is tuned to be an inherent understeerer. Always understeer, understeer and understeer. Whenever you push it harder and faster, understeer will get into the picture. The harder it corners, the more understeer it shows. Now we don't know why BMW needs rear-wheel-drive and an engine locating behind the front axle to create an understeerer. "
Frankly I am surprised this has not been discussed in the forum before. Maybe people don't recognize it for what it is or maybe they don't drive the car hard enough to realize the problem.
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It's been very well discussed that BMW sets up their cars (indeed, *EVERY* car manufacturer does this) for understeer as the primary response, because it's *generally* safer for most drivers. Even cars whose basic design (rear or mid-engined) would be expected to exhibit oversteer have tuned their cars to exhibit understeer.
You just haven't looked for articles discussing this.
FloydR
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wrote

My rear engined '65 Corvair could be set up to oversteer by changing the stock 15F, 27R tire pressures to about 30F, 30R. Of course, a 10 mph side wind would then blow the car off the road at any speed over 35 mph, but when you're young and adventurous...

You're right - Grinder needs to get out more. Just about every Road & Track BMW test indicates "mild" as opposed to "moderate" or "heavy" understeer and usually describes BMW steering as excellent.
Tom K.
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wrote

The problem is you are looking at ALL BMWs. I am concentrating on the Z4. It's unfortunate Homers are unable to recognize understeer much less too afraid to put a car into that type of situation.
Try google - 18000 hits on Z4 and understeer.
Took me less than 2 minutes to find (by the way, nobody referred to as the understeer as an excellent attribute).
"This sensory satellite delay does little to bring you in phase with the Z4's responses, and combined with the numb electrically-assisted (a first for a BMW), non-linear steering and the chassis' tendency towards steady-state understeer, it's no wonder things can feel slightly out of kilter when you're pressing on."
"Sadly, when we pitched it against the Porsche Cayman S (097), it revealed a propensity for understeer and a confidence-denting sense of disunity between the front and rear ends. "
"Out on the fabulous Jerez circuit, the dull steering doesn't really dent your progress, but the Z4 M's quite pronounced understeer does. "
"Basically, it is tuned to be an inherent understeerer. Always understeer, understeer and understeer. Whenever you push it harder and faster, understeer will get into the picture. The harder it corners, the more understeer it shows. Now we don't know why BMW needs rear-wheel-drive and an engine locating behind the front axle to create an understeerer. "
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wrote

It's a matter of degree. I have not found any articles referring to understeer in Boxsters or the Toyota 2000 but have countless on the topic for Z4s.
And you are wrong. I have looked for Articles on this. Truth of the matter is you are grouping "most cars" when the topic at hand is a handful of sports cars.
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