E90Post
 


Extreme Powerhouse
 
BMW 3-Series (E90 E92) Forum > BMW E90/E92/E93 3-series General Forums > Regional Forums > Australia > change of wheels / tyres - car feels slower



Reply
 
Thread Tools Search this Thread
      08-29-2011, 07:08 AM   #1
bmwaddiction
Lieutenant
Australia
25
Rep
421
Posts

Drives: Lexus IS350 F Sport
Join Date: Feb 2010
Location: ACT

iTrader: (0)

change of wheels / tyres - car feels slower

Hi, just changed over from 18 inch CSL reps with Falken 452 tyres (225/40/18 front and 255/35/18 rears) to 17inch BMW OEM 185 style wheels (Bridgestone Potenzas RE50 RFT 225/45/17s).

Now I may be imagining it but the car definately feels not as responsive / fast as with my previous set up. Maybe its just the tyres adjusting to the new camber/toe settings for the car?

Any wheel/tyre experts care to comment?
Appreciate 0
      08-29-2011, 07:15 AM   #2
sbce90
Me Boosta
sbce90's Avatar
Australia
249
Rep
5,722
Posts

Drives: 320i / MB C63 / VW up!
Join Date: Jan 2010
Location: Sydney, Australia

iTrader: (3)

Could be a large variety of factors so it's difficult to say what the cause is.

It could be wheel+tyre mass differences resulting in greater unsprung mass and needing more effort to turn. But, 18" cast csl reps would probably be similar in mass to OEM EH2 17" wheel. However the 17" RFT tyre might be heavier than the nonrft 452s. Hard to say without knowing how much each component weighs.

Otherwise it could just be the friction between tyre and road causing it to feel slower. Maybe the stock RFTs have a greater frictional coefficient than the Falkens?
Appreciate 0
      08-29-2011, 03:51 PM   #3
QLD
Captain
QLD's Avatar
44
Rep
913
Posts

Drives: 2010 LCI E92 - Mineral White
Join Date: Dec 2010
Location: ...

iTrader: (0)

We're still waiting for you to post that magic link????

http://www.e90post.com/forums/showthread.php?t=576567
__________________
.
.



..sweet torquin' diesel!
Appreciate 0
      08-29-2011, 10:23 PM   #4
John_01
Colonel
John_01's Avatar
Australia
232
Rep
2,643
Posts

Drives: E90 325i, E82 135i
Join Date: Mar 2009
Location: Sydney, Australia

iTrader: (0)

I think its possible you have added up to 2kg per corner. Stock BMW rims are very heavy and runflats will also add an extra 0.8 ~ 1kg for each tyre. I think there is an effect on performance, but probably hard to notice unless you test it against a stopwatch.
Appreciate 0
      08-30-2011, 04:19 AM   #5
johnnydad
Captain
johnnydad's Avatar
Australia
108
Rep
931
Posts

Drives: 17 BMW M2 - 05 RS Clio 182 Cup
Join Date: Nov 2008
Location: Sydney, NSW

iTrader: (0)

Quote:
Originally Posted by John_01 View Post
I think its possible you have added up to 2kg per corner. Stock BMW rims are very heavy and runflats will also add an extra 0.8 ~ 1kg for each tyre. I think there is an effect on performance, but probably hard to notice unless you test it against a stopwatch.
I suspect that the swap from 18's to 17's would counteract any increase in weight from the RFT's, particularly going from 255 to 225 rears. CSL reps in 18x8.5/9.5 are, what, 11-12kg and IIRC the stock BMW 17's are around the 10-11kg mark (can't find the ref ATM).

Likewise rolling diameter is changed by a trivial amount, and if anything the car would be a trifle lower geared withe the 17's.

I'd also think rolling resistance is less with RFT's - especially as the Falken's are not known for that quality and tend to have a wider tread vs rim width than Bridgestones also.

Makes no sense
__________________
John
17 F87 M2 Pure - long beach blue
10 E91 320d LCI - space grey - black dakota - steptronic - innovations - 157s - front PDC - Konis
99 BMW Baby Racer - red; 05 Renaultsport Clio 182 Cup - French Racing Blue - Konis - Eibachs - Remus - Turinis
Appreciate 0
      08-30-2011, 04:51 AM   #6
John_01
Colonel
John_01's Avatar
Australia
232
Rep
2,643
Posts

Drives: E90 325i, E82 135i
Join Date: Mar 2009
Location: Sydney, Australia

iTrader: (0)

I've had my 194M 17" wheels on the scales and they weighed 12.8kg (F) and 13.1kg (R). The figure from the BMW catalogue of 10.36kg isn't very accurate in the case of my wheels.
Appreciate 0
      08-30-2011, 06:44 AM   #7
bmwaddiction
Lieutenant
Australia
25
Rep
421
Posts

Drives: Lexus IS350 F Sport
Join Date: Feb 2010
Location: ACT

iTrader: (0)

yeah it doesn't really make sense...once the RFTs wear out I will chuck a set of Falken 452 or Kumho KU31s on and will see if there is any difference
Appreciate 0
      08-30-2011, 03:06 PM   #8
pcockley
Banned
43
Rep
1,719
Posts

Drives: 335
Join Date: Apr 2011
Location: sydney

iTrader: (1)

Quote:
Originally Posted by bmwaddiction View Post
yeah it doesn't really make sense...once the RFTs wear out I will chuck a set of Falken 452 or Kumho KU31s on and will see if there is any difference
Michelin super sports FTW
Appreciate 0
      08-30-2011, 07:19 PM   #9
johnnydad
Captain
johnnydad's Avatar
Australia
108
Rep
931
Posts

Drives: 17 BMW M2 - 05 RS Clio 182 Cup
Join Date: Nov 2008
Location: Sydney, NSW

iTrader: (0)

KU31s were scary compared to Michelin Pilot Exaltos on my Renault.

Run away. Far away.
__________________
John
17 F87 M2 Pure - long beach blue
10 E91 320d LCI - space grey - black dakota - steptronic - innovations - 157s - front PDC - Konis
99 BMW Baby Racer - red; 05 Renaultsport Clio 182 Cup - French Racing Blue - Konis - Eibachs - Remus - Turinis
Appreciate 0
      08-31-2011, 02:06 AM   #10
bmwaddiction
Lieutenant
Australia
25
Rep
421
Posts

Drives: Lexus IS350 F Sport
Join Date: Feb 2010
Location: ACT

iTrader: (0)

i had a set of KU31s on my CSLs prior to Falken 452s and they performed very well (except for really fast wear on rear tyres - only 20000km out of them)
Appreciate 0
      08-31-2011, 02:21 AM   #11
sbce90
Me Boosta
sbce90's Avatar
Australia
249
Rep
5,722
Posts

Drives: 320i / MB C63 / VW up!
Join Date: Jan 2010
Location: Sydney, Australia

iTrader: (3)

I'm content with my KU31s. Good enough to 320i power and daily driving. However they are quite noisy and on the track my RFT PS2s performed better. In fact my RFT PS2s were generally better than Ku31s..
Appreciate 1
      08-31-2011, 03:24 AM   #12
pcockley
Banned
43
Rep
1,719
Posts

Drives: 335
Join Date: Apr 2011
Location: sydney

iTrader: (1)

Quote:
Originally Posted by SBC View Post
I'm content with my KU31s. Good enough to 320i power and daily driving. However they are quite noisy and on the track my RFT PS2s performed better. In fact my RFT PS2s were generally better than Ku31s..
Shit if rft's are better, I still say super sports all the way FTW
Appreciate 0
      08-31-2011, 05:41 AM   #13
johnnydad
Captain
johnnydad's Avatar
Australia
108
Rep
931
Posts

Drives: 17 BMW M2 - 05 RS Clio 182 Cup
Join Date: Nov 2008
Location: Sydney, NSW

iTrader: (0)

Quote:
Originally Posted by SBC View Post
I'm content with my KU31s. Good enough to 320i power and daily driving. However they are quite noisy and on the track my RFT PS2s performed better. In fact my RFT PS2s were generally better than Ku31s..
I bow to your superior skillz

Seriously though, the Renault is the complete opposite of the BMWs so I probably shouldn't extrapolate.
__________________
John
17 F87 M2 Pure - long beach blue
10 E91 320d LCI - space grey - black dakota - steptronic - innovations - 157s - front PDC - Konis
99 BMW Baby Racer - red; 05 Renaultsport Clio 182 Cup - French Racing Blue - Konis - Eibachs - Remus - Turinis
Appreciate 0
      08-31-2011, 08:21 AM   #14
bmwaddiction
Lieutenant
Australia
25
Rep
421
Posts

Drives: Lexus IS350 F Sport
Join Date: Feb 2010
Location: ACT

iTrader: (0)

i had a set of KU31s on my CSLs prior to Falken 452s and they performed very well (except for really fast wear on rear tyres - only 20000km out of them)
Appreciate 0
      08-31-2011, 08:48 AM   #15
sbce90
Me Boosta
sbce90's Avatar
Australia
249
Rep
5,722
Posts

Drives: 320i / MB C63 / VW up!
Join Date: Jan 2010
Location: Sydney, Australia

iTrader: (3)

Quote:
Originally Posted by johnnydad View Post
I bow to your superior skillz
..err not sure if serious - re mdtc times yeah?
Appreciate 0
      09-01-2011, 02:06 AM   #16
johnnydad
Captain
johnnydad's Avatar
Australia
108
Rep
931
Posts

Drives: 17 BMW M2 - 05 RS Clio 182 Cup
Join Date: Nov 2008
Location: Sydney, NSW

iTrader: (0)

Quote:
Originally Posted by SBC View Post
..err not sure if serious - re mdtc times yeah?
Taming KU31s = Respect

[Not having a dig, wasn't party to MDTC times ]
__________________
John
17 F87 M2 Pure - long beach blue
10 E91 320d LCI - space grey - black dakota - steptronic - innovations - 157s - front PDC - Konis
99 BMW Baby Racer - red; 05 Renaultsport Clio 182 Cup - French Racing Blue - Konis - Eibachs - Remus - Turinis
Appreciate 0
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



All times are GMT -5. The time now is 01:02 PM.




e90post
Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
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