A Cars forum. AutoBanter

If this is your first visit, be sure to check out the FAQ by clicking the link above. You may have to register before you can post: click the register link above to proceed. To start viewing messages, select the forum that you want to visit from the selection below.

Go Back   Home » AutoBanter forum » Auto makers » BMW
Site Map Home Register Authors List Search Today's Posts Mark Forums Read Web Partners

I don't like electric assist stearing.



 
 
Thread Tools Display Modes
  #21  
Old March 15th 07, 05:33 PM posted to alt.autos.bmw
Fred W
external usenet poster
 
Posts: 326
Default I don't like electric assist stearing.

grinder wrote:
> "Fred W" > wrote in message
> . ..
>
>>grinder wrote:
>>
>>>"Fred W" > wrote in message
om...
>>>
>>>
>>>>grinder wrote:
>>>>
>>>>
>>>>>"Fred W" > wrote in message
>>>>>news:rcudnVO4druAGmnYnZ2dnUVZ_s3inZ2d@comcast .com...
>>>>>
>>>>>
>>>>>
>>>>>>grinder wrote:
>>>>>>
>>>>>>
>>>>>>
>>>>>>>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.
>>>>>>
>>>>>>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
>>>>>
>>>>>
>>>>>Braces will reduce flex on hard corners thereby keeping more tire on the
>>>>>road and improving cornering performance.
>>>>
>>>>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.
>>>>
>>>>--
>>>>-Fred W
>>>
>>>
>>>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.

>>
>>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.
>>
>>--
>>-Fred W

>
>
> 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")."
>
>


Correct, just as I said above. And this has zero to do with the
electric steering assist.

--
-Fred W
Ads
  #22  
Old March 15th 07, 05:36 PM posted to alt.autos.bmw
Fred W
external usenet poster
 
Posts: 326
Default I don't like electric assist stearing.

grinder wrote:
> "adder1969" > wrote in message
> oups.com...
>
>>On Mar 15, 2:24 pm, "grinder" > wrote:
>>
>>>"Fred W" > wrote in message
>>>
om...
>>>
>>>
>>>
>>>
>>>
>>>
>>>>grinder wrote:
>>>>
>>>>>"Fred W" > wrote in message
>>>>>news:ftqdnROx0ds4CGjYnZ2dnUVZ_o6gnZ2d@comcast .com...
>>>
>>>>>>grinder wrote:
>>>
>>>>>>>"Fred W" > wrote in message
>>>>>>>news:rcudnVO4druAGmnYnZ2dnUVZ_s3inZ2d@comca st.com...
>>>
>>>>>>>>grinder wrote:
>>>
>>>>>>>>>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.
>>>
>>>>>>>>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
>>>
>>>>>>>Braces will reduce flex on hard corners thereby keeping more tire on
>>>>>>>the
>>>>>>>road and improving cornering performance.
>>>
>>>>>>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.
>>>
>>>>>>--
>>>>>>-Fred W
>>>
>>>>>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.
>>>
>>>>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.
>>>
>>>>--
>>>>-Fred W
>>>
>>>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.- Hide quoted text -
>>>
>>>- Show quoted text -

>>
>>
>>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.
>>
>>

>
>
> 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.
>
>


Yes. The car understeers. But your complaint was the electric assist.
Know how I know this to be true? Read the subject line (above) that
you entered.

--
-Fred W
  #23  
Old March 15th 07, 05:55 PM posted to alt.autos.bmw
Tom K.
external usenet poster
 
Posts: 257
Default I don't like electric assist stearing.


"Floyd Rogers" > wrote in message
...
> "grinder" > wrote
>> "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.

>
> 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.
>

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 just haven't looked for articles discussing this.


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.


  #24  
Old March 15th 07, 08:16 PM posted to alt.autos.bmw
grinder
external usenet poster
 
Posts: 105
Default I don't like electric assist stearing.


"Fred W" > wrote in message
. ..
> grinder wrote:
>> "Fred W" > wrote in message
>> . ..
>>
>>>grinder wrote:
>>>
>>>>"Fred W" > wrote in message
>>>>news:ftqdnROx0ds4CGjYnZ2dnUVZ_o6gnZ2d@comcast. com...
>>>>
>>>>
>>>>>grinder wrote:
>>>>>
>>>>>
>>>>>>"Fred W" > wrote in message
>>>>>>news:rcudnVO4druAGmnYnZ2dnUVZ_s3inZ2d@comcas t.com...
>>>>>>
>>>>>>
>>>>>>
>>>>>>>grinder wrote:
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>>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.
>>>>>>>
>>>>>>>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
>>>>>>
>>>>>>
>>>>>>Braces will reduce flex on hard corners thereby keeping more tire on
>>>>>>the road and improving cornering performance.
>>>>>
>>>>>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.
>>>>>
>>>>>--
>>>>>-Fred W
>>>>
>>>>
>>>>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.
>>>
>>>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.
>>>
>>>--
>>>-Fred W

>>
>>
>> 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")."

>
> Correct, just as I said above. And this has zero to do with the electric
> steering assist.
>
> --
> -Fred W


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.


  #25  
Old March 15th 07, 08:18 PM posted to alt.autos.bmw
grinder
external usenet poster
 
Posts: 105
Default I don't like electric assist stearing.


"Fred W" > wrote in message
. ..
> grinder wrote:
>> "adder1969" > wrote in message
>> oups.com...
>>
>>>On Mar 15, 2:24 pm, "grinder" > wrote:
>>>
>>>>"Fred W" > wrote in message
>>>>
>>>>news:TLidnYNt9rfhfWrYnZ2dnUVZ_hKdnZ2d@comcast. com...
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>
>>>>>grinder wrote:
>>>>>
>>>>>>"Fred W" > wrote in message
>>>>>>news:ftqdnROx0ds4CGjYnZ2dnUVZ_o6gnZ2d@comcas t.com...
>>>>
>>>>>>>grinder wrote:
>>>>
>>>>>>>>"Fred W" > wrote in message
>>>>>>>>news:rcudnVO4druAGmnYnZ2dnUVZ_s3inZ2d@comc ast.com...
>>>>
>>>>>>>>>grinder wrote:
>>>>
>>>>>>>>>>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.
>>>>
>>>>>>>>>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
>>>>
>>>>>>>>Braces will reduce flex on hard corners thereby keeping more tire on
>>>>>>>>the
>>>>>>>>road and improving cornering performance.
>>>>
>>>>>>>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.
>>>>
>>>>>>>--
>>>>>>>-Fred W
>>>>
>>>>>>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.
>>>>
>>>>>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.
>>>>
>>>>>--
>>>>>-Fred W
>>>>
>>>>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.- Hide quoted text -
>>>>
>>>>- Show quoted text -
>>>
>>>
>>>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.
>>>
>>>

>>
>>
>> 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.

>
> Yes. The car understeers. But your complaint was the electric assist.
> Know how I know this to be true? Read the subject line (above) that you
> entered.
>
> --
> -Fred W


You're right. I was wrong to attribute it to electrical assist steering.

That should make you feel better.

Unfortunately the understeer is still there regardless of the source.


  #26  
Old March 15th 07, 08:20 PM posted to alt.autos.bmw
grinder
external usenet poster
 
Posts: 105
Default I don't like electric assist stearing.


"Floyd Rogers" > wrote in message
...
> "grinder" > wrote
>> "adder1969" > wrote
>>> 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.

>>
>> 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.

>
> 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
>


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.



  #27  
Old March 15th 07, 08:30 PM posted to alt.autos.bmw
grinder
external usenet poster
 
Posts: 105
Default I don't like electric assist stearing.


"Tom K." > wrote in message
. ..
>
> "Floyd Rogers" > wrote in message
> ...
>> "grinder" > wrote
>>> "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.

>>
>> 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.
>>

> 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 just haven't looked for articles discussing this.

>
> 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.
>


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. "


  #28  
Old March 15th 07, 10:05 PM posted to alt.autos.bmw
Floyd Rogers[_1_]
external usenet poster
 
Posts: 689
Default I don't like electric assist stearing.

"grinder" > wrote
> "Floyd Rogers" > wrote
>> "grinder" > wrote

> ...
>>> 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.

>>
>> 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.

>
> 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.


I may have been confusing rec.autos.driving postings with postings here -
I've certainly seen many postings on this matter.

However, you are wrong if you think that a Boxster (my wife has one)
does not understeer - at least for initial and middling responses. My
NSX understeered. Modern Porsche 911's are tuned for understeer -
although if you go to the limit it oversteers. My statement stands that
all cars (including BMWs) understeer.

FloydR


  #29  
Old March 15th 07, 11:12 PM posted to alt.autos.bmw
Fred W
external usenet poster
 
Posts: 326
Default I don't like electric assist stearing.

grinder wrote:
> "Fred W" > wrote in message
> . ..
>
>>grinder wrote:
>>
>>>"adder1969" > wrote in message
egroups.com...
>>>
>>>
>>>>On Mar 15, 2:24 pm, "grinder" > wrote:
>>>>
>>>>
>>>>>"Fred W" > wrote in message
>>>>>
>>>>>news:TLidnYNt9rfhfWrYnZ2dnUVZ_hKdnZ2d@comcast .com...
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>
>>>>>>grinder wrote:
>>>>>>
>>>>>>
>>>>>>>"Fred W" > wrote in message
>>>>>>>news:ftqdnROx0ds4CGjYnZ2dnUVZ_o6gnZ2d@comca st.com...
>>>>>
>>>>>>>>grinder wrote:
>>>>>
>>>>>>>>>"Fred W" > wrote in message
>>>>>>>>>news:rcudnVO4druAGmnYnZ2dnUVZ_s3inZ2d@com cast.com...
>>>>>
>>>>>>>>>>grinder wrote:
>>>>>
>>>>>>>>>>>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.
>>>>>
>>>>>>>>>>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
>>>>>
>>>>>>>>>Braces will reduce flex on hard corners thereby keeping more tire on
>>>>>>>>>the
>>>>>>>>>road and improving cornering performance.
>>>>>
>>>>>>>>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.
>>>>>
>>>>>>>>--
>>>>>>>>-Fred W
>>>>>
>>>>>>>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.
>>>>>
>>>>>>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.
>>>>>
>>>>>>--
>>>>>>-Fred W
>>>>>
>>>>>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.- Hide quoted text -
>>>>>
>>>>>- Show quoted text -
>>>>
>>>>
>>>>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.
>>>>
>>>>
>>>
>>>
>>>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.

>>
>>Yes. The car understeers. But your complaint was the electric assist.
>>Know how I know this to be true? Read the subject line (above) that you
>>entered.
>>
>>--
>>-Fred W

>
>
> You're right. I was wrong to attribute it to electrical assist steering.
>
> That should make you feel better.
>
> Unfortunately the understeer is still there regardless of the source.
>
>


OK, sorry to be redundant.

So... now we get to the crux of the matter. The car exhibits more
understeer than you'd like.

How to reduce understeer (or induce oversteer if taken far enough):

Increase front tire pressure
Decrease Rear tire pressure
Shave Front tires (decrease tread depth)
Wider Front Tires
Narrower Rear Tires
Make Front Camber more Negative
Make Front Caster more Positive
Reduce Front Toe-in
Softer front swap bar
Stiffer rear sway Bar
Soften front springs
Stiffen rear springs
Softer front shocks
Stiffer rear shocks

So you see... you aren't exactly stuck with the handling you have right
now.

Many BMWs come with staggered tires. Get rid of that as a first step.
Put the same size tire and wheel on both axles and you may find things
are much more "balanced" right there. Of course it won't look like a
dragster anymore... C'est la vie.

--
-Fred W
  #30  
Old March 16th 07, 01:00 AM posted to alt.autos.bmw
Dave Plowman (News)
external usenet poster
 
Posts: 1,533
Default I don't like electric assist stearing.

In article >,
Floyd Rogers > wrote:
> My statement stands that all cars (including BMWs) understeer.


Modern ones yes - and rightly so for safety in extremis. But it's not so
long ago the semi trailing arm equipped ones like the E28 etc could
oversteer pretty easily and bite the unwary.

The very first BMW I drove was a 525 auto - the one before the E28 - and
lost it at a pretty low speed on a wet roundabout. No harm was done and I
caught it before it spun, but it surprised me - my car was a considerably
more powerful auto and would have taken the same treatment easily. But
then it had a De Dion rear axle.

--
*Hard work pays off in the future. Laziness pays off now *

Dave Plowman London SW
To e-mail, change noise into sound.
 




Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Forum Jump

Similar Threads
Thread Thread Starter Forum Replies Last Post
97 TJ stearing box removal [email protected] Jeep 2 December 17th 06 09:44 PM
Replace stearing wheel on car w/airbag? [email protected] General 2 March 26th 06 02:51 PM
Creeky stearing! Who? Chrysler 3 September 14th 05 03:00 PM
Stearing column squeak Cheeky Bee via CarKB.com Audi 3 May 23rd 05 09:57 AM
2000 Jimmy -- Stearing sluggish in 4 wheel drive [email protected] Technology 1 December 30th 04 01:08 PM


All times are GMT +1. The time now is 07:13 AM.


Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2024, Jelsoft Enterprises Ltd.
Copyright ©2004-2024 AutoBanter.
The comments are property of their posters.