XBimmers X1   XBimmers X1
  XBimmers X1

Go Back   XBimmers | BMW X1 Forum > BMW X1 Forums > General BMW X1 (E84) Forum

Post Reply
 
Thread Tools Search this Thread
      07-09-2012, 02:32 PM   #23
mkoesel
Moderator
United_States
177

 
Drives: 2015 SO/CSAT F80 M3
Join Date: Jun 2006
Location: Canton, MI


Posts: 13,784
iTrader: (1)

Quote:
Originally Posted by investor27 View Post
To be honest with you. Everything I've read during the debut of the X1 have indicated that both X1s with the N20 4-cylinder engine come with the hydraulic steering, with Servotronic being an option. The xDrive35i has electric power steering with Servotronic.
I see.

Well, given that the BMW website does not mention electric power steering for the sDrive28i model, I think it is much more likely that it has traditional power steering just like the xDrive28i model does. This also makes much more sense from a parts-sharing perspective (the engine will thus drive the same accesories in either case).

Quote:
The only piece of relevant information (or confirmation) that I got from his response was that the Servotronic option doesn't not cause the hydraulic power steering to be replaced with an electric power steering.
Yes, this has been a source of confusion before. As the blurb I quote above points out, Servotronic is really a technology developed for traditional non-electric power steering systems. Newer electric systems can vary steering assistance simply using software since by their vary design they control the steering motor's input independently of the vehicle's engine.

It is curious, though, that BMW lists Servotronic as a standard feature for the apparently EPS-equipped xDrive35i (assuming the information on BMW's website at the link provided above is correct - thanks CanadianDriver and X1driver). I suppose this is just the marketing department wanting to show the additional content vs. the 28i models. The fact is that BMW has yet to produce a vehicle with EPS that does not have vehicle speed (rather than engine speed as is typical) dependent steering, and I don't see the X1 becoming an exception.
__________________
A gen-u-ine BMW eff-eight-zero with them tandem clutches in the transmission and that dad gum sun roof on the top-a da cawr.
Appreciate 0
      07-17-2012, 11:24 PM   #24
X1driver
Private
5

 
Drives: BMW X1
Join Date: Feb 2012
Location: Canada


Posts: 58
iTrader: (0)

Now that the various reviews are available from major car magazines, the mystery is solved. Only the rear wheel drive sDrive has electric steering and all other xDrive (both 28 and 35) models have hydraulic steering. So we are happy to hear that hydraulic remains at least for two out of the three X1 models.
Appreciate 0
      07-18-2012, 02:19 AM   #25
mapezzul
Special Agent
United_States
26

 
mapezzul's Avatar
 
Drives: Depends on the day!
Join Date: Jul 2005
Location: Bavaria


Posts: 1,736
iTrader: (1)

Quote:
Originally Posted by X1driver View Post
Now that the various reviews are available from major car magazines, the mystery is solved. Only the rear wheel drive sDrive has electric steering and all other xDrive (both 28 and 35) models have hydraulic steering. So we are happy to hear that hydraulic remains at least for two out of the three X1 models.
That is correct- we went under the hood to figure it out and then inquired with the engineers.

The 28i sDrive is the only EPS system and remains that way even with "Servotronic" as they are able to add boost with EPS by adjusting the power to the motor.

The 35i comes with hydraulic servotronic which the 28ixDrive has available as an option. The EPS unit was unable to be packaged in the X1 with xDrive.

The best of the bunch is the xDrive in 28i form...
Appreciate 0
      07-18-2012, 08:30 AM   #26
mkoesel
Moderator
United_States
177

 
Drives: 2015 SO/CSAT F80 M3
Join Date: Jun 2006
Location: Canton, MI


Posts: 13,784
iTrader: (1)

Thanks for the information gentemen. I can't think of a more mysterious equipment conundrum in recent memory. I wonder if the sDrive models sold elsewhere (18i, 20i, 16d, 18d, 20d) also have EPAS? As noted earlier a BMW Press release confirms that the sDrive20d ED model does, at least.

So the Servotronic upsell for the sDrive28i is just programming then. How about that.
__________________
A gen-u-ine BMW eff-eight-zero with them tandem clutches in the transmission and that dad gum sun roof on the top-a da cawr.
Appreciate 0
      07-18-2012, 11:47 AM   #27
investor27
Private First Class
4

 
Drives:
Join Date: Nov 2007


Posts: 137
iTrader: (0)

Mapezzul. How's the drive with the Servotronic option on the xDrive28i? Is it comparable to the older 3 series? Thanks.

Quote:
Originally Posted by mapezzul View Post
That is correct- we went under the hood to figure it out and then inquired with the engineers.

The 28i sDrive is the only EPS system and remains that way even with "Servotronic" as they are able to add boost with EPS by adjusting the power to the motor.

The 35i comes with hydraulic servotronic which the 28ixDrive has available as an option. The EPS unit was unable to be packaged in the X1 with xDrive.

The best of the bunch is the xDrive in 28i form...
Appreciate 0
      07-18-2012, 12:04 PM   #28
mapezzul
Special Agent
United_States
26

 
mapezzul's Avatar
 
Drives: Depends on the day!
Join Date: Jul 2005
Location: Bavaria


Posts: 1,736
iTrader: (1)

Quote:
Originally Posted by investor27 View Post
Mapezzul. How's the drive with the Servotronic option on the xDrive28i? Is it comparable to the older 3 series? Thanks.
It still is a little light for my liking at low speeds (as even the M3 is but nowhere near Audi over boost!) but it is accurate and has a bunch of feel- it is basically like driving an E90 with xDrive in feel. The X1 is one of the final BMWs to come to the US new with a hydraulic rack. If you spend time in parking lots or traffic servotronic is a no brainer- BMW has by far the best curve with that system.

The packaging constraints were quite obvious when all three variants were examined- xDrive and the N55 take up a lot of space in that engine bay and even in the 4 cylinder the EPS would not fit due to motor placement (a good thing if you as k me!).

It is a great ride- I have my issues with it as I wrote about elsewhere in my review but it may be then next family car we own as the price is right.
Appreciate 0
      07-18-2012, 02:08 PM   #29
investor27
Private First Class
4

 
Drives:
Join Date: Nov 2007


Posts: 137
iTrader: (0)

Great! Thanks for the reply. Sounds wonderful.
Appreciate 0
      12-18-2012, 12:14 AM   #30
prosgal73
New Member
0

 
Drives: Nissan
Join Date: Oct 2012
Location: CA


Posts: 16
iTrader: (0)

can't decide b/w xdrive or sdrive? help!

hello can't decide but i know people go with the xdrive for the hydraulic steering...any thoughts? i live it so cal so don't technically need the AWD but i plan to purchase the car and was wondering if one or the other steerings is more reliable, thanks!

Quote:
Originally Posted by X1driver View Post
Now that the various reviews are available from major car magazines, the mystery is solved. Only the rear wheel drive sDrive has electric steering and all other xDrive (both 28 and 35) models have hydraulic steering. So we are happy to hear that hydraulic remains at least for two out of the three X1 models.
Appreciate 0
      12-18-2012, 06:23 PM   #31
Lucky13
Lucky13
United_States
16

 
Drives: 2014 M235 manual
Join Date: Mar 2007
Location: Columbia, S.C.


Posts: 1,222
iTrader: (0)

To be honest I have an E93 335 which has hydraulic steering and an X1 sdrive and I don't see a big difference. Yes it's electric but they did a pretty good job with it. It's a little lighter in feel but certainly fun to drive with plenty of feedback.
__________________
1995 325i, 1996 328ci, 1997 528i, 1997 Z3 2.8,2001 X5 3.0, 2001 330i Convertible, 2002 M3 Convertible, 2003 M3 Coupe, 2004 M3 Coupe, 2004 Z4 3.0, 2004 X3 3.0,
2007 X3 3.0, 2007 335i Convertible, 2013 X1 28 sdrive,
2014 M235 manual
Appreciate 0
      12-18-2012, 11:21 PM   #32
nospam
Captain
8

 
Drives: X1 x28i; 128i; S2000
Join Date: Jul 2010
Location: Orange County, CA


Posts: 672
iTrader: (0)

I believe the E9x 335s have servotronic standard. I actually prefer the variable sports steering on the F30 to the steering on my E90 335. The steering on our 128i is superior (which is partly why we sold the 335 and kept the 128). I haven't driven the sDrive since knew I wanted AWD w/DPC. I went x28i largely due to the 8AT and no servotronic.
Appreciate 0
      12-19-2012, 12:24 PM   #33
nospam
Captain
8

 
Drives: X1 x28i; 128i; S2000
Join Date: Jul 2010
Location: Orange County, CA


Posts: 672
iTrader: (0)

Apparently both the e82 128i and 135i have servotronic assist standard. My observations on differences is steering vs E90 335i must be more due to vehicle size/weight and perhaps a corresponding difference in amount of servotronic assist. I haven't test driven the x35i, only the x28i with no servo. My wife liked the non-servo feel and said she didn't need any assist added.
Appreciate 0
      12-19-2012, 12:30 PM   #34
Red Bread
Brigadier General
United_States
45

 
Drives: My wife's car
Join Date: Oct 2008
Location: Dallas, TX


Posts: 4,304
iTrader: (0)

Garage List
Quote:
Originally Posted by nospam View Post
Apparently both the e82 128i and 135i have servotronic assist standard. My observations on differences is steering vs E90 335i must be more due to vehicle size/weight and perhaps a corresponding difference in amount of servotronic assist. I haven't test driven the x35i, only the x28i with no servo. My wife liked the non-servo feel and said she didn't need any assist added.
Servotronic was an option on earlier E82's, but it could be standard now. I know our 2008 135i did not have it. However the steering feel of our X1 35i is very similar to the E82, the awd impacts steering feel more than Servotronic though.
Appreciate 0
      12-19-2012, 05:00 PM   #35
nospam
Captain
8

 
Drives: X1 x28i; 128i; S2000
Join Date: Jul 2010
Location: Orange County, CA


Posts: 672
iTrader: (0)

BMW's official documentation sure is confusing!

E82 Complete Vehicle Manual reads:
Quote:
The following steering systems are fitted in E82 vehicles:
Conventional rack-and-pinion steering with Servotronic assist hydraulic pump
(vane cell pump) this is the standard steering for all 128i and 135i vehicles.
Active Steering with hydraulic pump and ECO valve is available as an option.
Active Steering in the E82 features the following optimization measures carried over
from the E70 or E6x LCI:
Modified planetary gearing
New control module
Absence of the cumulative steering-angle sensor on the rack.
Note: The new procedure for initializing the Active Steering (as in the E70) now
also applies to the E82. (because of the absence of the cumulative steering-
angle sensor).
There will be no electrical steering lock (ELV) in the US variant of the E82. This applies to
vehicles with automatic transmission and to vehicles with manual transmission.
While the E82 M Complete Vehicle Manual reads:
Quote:
2.1.8. Standard/optional equipment
Standard equipment compared with 135i

Servotronic

4.4.2. Steering
The hydraulically assisted rack-and-pinion steering has been carried over unchanged from the BMW
E9x M3. With an average overall ratio for the variable gearing of 12.5:1 it is direct as a sports model
(16:1 on 135i). The power assistance is controlled by the Junction Box control unit via the Servotronic
valve according to a set sports characteristic. Active steering is not offered.
Quote:
Originally Posted by John_01 View Post
The word 'servotronic' is confusing, because it was used for an advanced hydraulic power steering system since about 10 years ago or more.
I can only conclude that "Servotronic assist hydraulic pump" is BMW's standard hydraulic steering like on the x28i and not the servotronic option that is standard on the x35i (nonadjustable) and 1M (adjustable).

According to RealOEM non of the US non-M E8x 1-series or E9x have servotronic standard (there is a retrofit). I'm not sure how to quantify my preference for the 128i steering over 335i other than vehicle size. Or perhaps there is a different steering ratio between the E8x 1 and E9x 3 series.
Appreciate 0
      12-20-2012, 10:19 PM   #36
nospam
Captain
8

 
Drives: X1 x28i; 128i; S2000
Join Date: Jul 2010
Location: Orange County, CA


Posts: 672
iTrader: (0)

Hydraulic steering ratios (lower = sportier/more responsive)

E46 M3 (no servotronic) - 15.6
E9x M3 (servotronic/variable) - 12.5 averaged
E8x M Coupe (servotronic/variable) - 12.5 averaged
E9x 3 Series (non-M) - 16
E8x 1 Series (non-M) - 16
E84 X1 - 18.5

There doesn't seem to be any data in regards to the amount of hydraulic assistance on non servotronic vehicles (servotronic varies assistance based on vehicle speed on X1). I'm guessing that the E9x 3 series have more hydraulic assistance than the E8x 1 series based on my own driving impressions.

I drove my parents F30 328i with EPS+ (variable sport steering) again yesterday. The EPS+ system seems to be emulating the adjustable hydraulic/servotronic systems of the M vehicles (I've never driven an M), while steering is effortless when parking. I hope that this is an option on the sDrive X1 soon for those owners who don't need AWD (I believe it is available on X3).
Appreciate 0
      12-21-2012, 04:23 PM   #37
Lucky13
Lucky13
United_States
16

 
Drives: 2014 M235 manual
Join Date: Mar 2007
Location: Columbia, S.C.


Posts: 1,222
iTrader: (0)

I happily traded the lower weight, better handling, slightly faster and better gas mileage of the sdrive for the Xdrive. It's not the like the difference between driving an M3 and a 335 its slightly better driving feel. I guess everyone should buy a Cadillac ATS instead of a 3 series because it has slightly better steering feel according to all car magazines.
__________________
1995 325i, 1996 328ci, 1997 528i, 1997 Z3 2.8,2001 X5 3.0, 2001 330i Convertible, 2002 M3 Convertible, 2003 M3 Coupe, 2004 M3 Coupe, 2004 Z4 3.0, 2004 X3 3.0,
2007 X3 3.0, 2007 335i Convertible, 2013 X1 28 sdrive,
2014 M235 manual
Appreciate 0
      01-01-2013, 01:09 PM   #38
FStephenMasek
New Member
United_States
1

 
FStephenMasek's Avatar
 
Drives: 2006 Ford Explorer EB V8 RWD
Join Date: Dec 2012
Location: southern California


Posts: 21
iTrader: (0)

Quote:
Originally Posted by mkoesel View Post
Electric (not Electronic as you said - though your word choice could be due to your nationality) power steering uses a seperate electric motor to drive the hydraulic system.
A car magazine sometime in 2012 showed the BMW electric power steering, and the motor is integreated into the steering column, not driving a hydraulic pump.
Appreciate 0
Post Reply

Bookmarks

Thread Tools Search this Thread
Search this Thread:

Advanced Search

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

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


All times are GMT -5. The time now is 07:54 PM.




xbimmers
Powered by vBulletin® Version 3.7.0
Copyright ©2000 - 2014, Jelsoft Enterprises Ltd.
1Addicts.com, BIMMERPOST.com, E90Post.com, F30Post.com, M3Post.com, ZPost.com, 5Post.com, 6Post.com, 7Post.com, XBimmers.com logo and trademark are properties of BIMMERPOST