Rolling diameter effect on xi

Chrisred · 04-07-2012, 10:23 PM

Have 235/35/19 265/30/19 and rolling diameter is 0.8%.
Should run 235/3519 275/30/19 so rolling diameter is 0.02%

Will this small 0.8% difference actually ruin my awd system??

Eko · 04-07-2012, 11:24 PM

no. Try google next time

1000000000 threads about this... you probably get .8% difference from turning wear on your tires. haha

Eko · 04-07-2012, 11:24 PM

oops sorry i was thinking .08% difference. but still .8 should be ok.

Chrisred · 04-08-2012, 01:31 AM

Doesn't seem much but dealer told me and some other users that it could lead to a problem

Ctm309 · 04-08-2012, 12:12 PM

It seems that the collective theory is: 1% and under will not cause any problem.

terbow2 · 04-08-2012, 05:51 PM

Is running 225/35/19 fronts and 265/30/19 rears to far out of rolling diameter? Was trying to get some advice before I mount the tires I have. Thank you for your help

krazyking · 04-09-2012, 03:04 PM

Hey guys,

I'm planning on getting a new set of Wheels + Tires. Here is the setup I have in mind:

18x8.5 ET35 with 235/40/18
18x9.5 ET35 with 255/35/18

Can I rock the 235's in the front without a problem or would it cause a trouble with the rolling diameter?

Er3k · 04-09-2012, 08:26 PM

Quote:

Originally Posted by krazyking

Hey guys,

I'm planning on getting a new set of Wheels + Tires. Here is the setup I have in mind:

18x8.5 ET35 with 235/40/18
18x9.5 ET35 with 255/35/18

Can I rock the 235's in the front without a problem or would it cause a trouble with the rolling diameter?

Not all tire brands are equally matched as far as roll diameter is concerned. You have to make sure that your tire combo has no more than 3 revolutions per mile front to back. My Hankooks are 235/35/19 front & 275/30/19 rear, the fronts roll 816 revolutions per mile and the backs roll 813 revolutions per mile. Go to Tirerack.com and check the tire specs before you chose your combo, different brands have different revs per mile for each tire combo.

Fozzy · 04-17-2012, 09:28 PM

Quote:

Originally Posted by E. Staggered

Not all tire brands are equally matched as far as roll diameter is concerned. You have to make sure that your tire combo has no more than 3 revolutions per mile front to back. My Hankooks are 235/35/19 front & 275/30/19 rear, the fronts roll 816 revolutions per mile and the backs roll 813 revolutions per mile. Go to Tirerack.com and check the tire specs before you chose your combo, different brands have different revs per mile for each tire combo.

interesting. Where did you get the 3 revolutions per mile info.?

dangeris · 04-18-2012, 06:19 AM

Quote:

Originally Posted by krazyking

Hey guys,

I'm planning on getting a new set of Wheels + Tires. Here is the setup I have in mind:

18x8.5 ET35 with 235/40/18
18x9.5 ET35 with 255/35/18

Can I rock the 235's in the front without a problem or would it cause a trouble with the rolling diameter?

I'm rolling with the same setup with no problem.

deezofchuck · 04-18-2012, 10:53 AM

Quote:

Originally Posted by Fozzy

interesting. Where did you get the 3 revolutions per mile info.?

he just said go to tirerack.com and look at the F/R tire combo you want...there is a spec sheet tab and it will tell you the rev per mile for each tire - subtract the diff - for his it was 816F and 813R (3 rev/mi diff).

Er3k · 04-18-2012, 12:31 PM

Quote:

Originally Posted by Fozzy

interesting. Where did you get the 3 revolutions per mile info.?

The link below shows the exact same tires that are used when you order a staggered setup from the dealer on an XI model. 2 of my friends ordered the XI's with a staggered setup with the Bridgestone RE050A I Potenza's (18inch) and they have had no problems whatsoever. My buddy has been running his 07' 335xi for 5 years this way. If you notice, they are 3 revs difference per mile front/back but these particular tires are runflats, and according to tire rack, the are "OE BMW USE ONLY".

http://www.tirerack.com/tires/tires....=yes&tab=Specs

Eko · 04-18-2012, 03:07 PM

Dont some 335xi come with staggered setup stock?

moveit · 04-18-2012, 08:53 PM

I just put staggered style 162's on my car and it seems like there is a loss of power. Should I be concerned?

225/40/18 on 8" wheels (830 rpm)
265/35/18 on 8.5" wheels (823 rpm)

Tires are Potenza RE760. Difference in revs per minute is 7. How does this effect the drivetrain?

Er3k · 04-18-2012, 11:43 PM

Quote:

Originally Posted by Eko

Dont some 335xi come with staggered setup stock?

I think so, my buddy had the option to go staggered on 18's or save money for the 17's on a square setup. But the Bridgestones in the link are the tires that were used.

Er3k · 04-18-2012, 11:52 PM

Quote:

Originally Posted by moveit

I just put staggered style 162's on my car and it seems like there is a loss of power. Should I be concerned?

225/40/18 on 8" wheels (830 rpm)
265/35/18 on 8.5" wheels (823 rpm)

Tires are Potenza RE760. Difference in revs per minute is 7. How does this effect the drivetrain?

Shouldn't your rears be 255, correct me if I'm wrong but I thought that 225 & 255 were closer in diameter when paired together. The 265' are probably causing a lag in the transfer case because the revs per mile are a little further apart. I stuck with the 3 revs per mile like the guy at the BMW dealer to me to do.

krazyking · 04-19-2012, 10:19 AM

Yeah it should be 255 in the rear and not 265.

moonsin · 04-19-2012, 10:47 AM

Sooo...as long as it doesn't exceed 3 revs per mile you're okay?

i'm running Hankook ventus 225/35/19 front and 265/30/19 in the rear.
According to the tirerack fronts do 823 revs per mile vs. 821 for the rear (-2 difference)

Er3k · 04-19-2012, 01:38 PM

Quote:

Originally Posted by moonsin

Sooo...as long as it doesn't exceed 3 revs per mile you're okay?

i'm running Hankook ventus 225/35/19 front and 265/30/19 in the rear.
According to the tirerack fronts do 823 revs per mile vs. 821 for the rear (-2 difference)

:

Yup, that's close enough bro! Your good!!

In my opinion, the revs per mile seem to be those most important thing to worry about. Knowing each individual tire spec is key for the XI drivers.

moonsin · 04-19-2012, 05:26 PM

Quote:

Originally Posted by E. Staggered

:

Yup, that's close enough bro! Your good!!

In my opinion, the revs per mile seem to be those most important thing to worry about. Knowing each individual tire spec is key for the XI drivers.

awesome!

Babydragon · 04-21-2012, 04:39 PM

Ive been running 235 front and 275rear for over a year now. No problems at all, ever.

moveit · 04-21-2012, 09:53 PM

Quote:

Originally Posted by hajduk

Ive been running 235 front and 275rear for over a year now. No problems at all, ever.

How wide are your wheels and what aspect ratio for the tires? Also what kind of tires?

04-07-2012, 10:23 PM	#1
Chrisred Captain 81 Rep 788 Posts Drives: BMW 335xi coupe Join Date: Jan 2010 Location: Montreal, Canada iTrader: (0)	Have 235/35/19 265/30/19 and rolling diameter is 0.8%. Should run 235/3519 275/30/19 so rolling diameter is 0.02% Will this small 0.8% difference actually ruin my awd system?? __________________ JB4 Trebila tuned cp-e IC AMS exhaust BMS DCI AR DP's METH RB TURBO 19" VMR VB3 Stoptech BBK TC KLINE VORSHLAG SPEC STG 3 OSS design
	Appreciate 0 Tweet Quote

04-07-2012, 11:24 PM	#2
Eko Private First Class 4 Rep 103 Posts Drives: E90 335xi Join Date: May 2011 Location: Seattle iTrader: (0)	no. Try google next time 1000000000 threads about this... you probably get .8% difference from turning wear on your tires. haha __________________ ----------------------------- 2008 335xi Montego Blue
	Appreciate 0 Quote

04-07-2012, 11:24 PM	#3
Eko Private First Class 4 Rep 103 Posts Drives: E90 335xi Join Date: May 2011 Location: Seattle iTrader: (0)	oops sorry i was thinking .08% difference. but still .8 should be ok. __________________ ----------------------------- 2008 335xi Montego Blue
	Appreciate 0 Quote

04-08-2012, 01:31 AM	#4
Chrisred Captain 81 Rep 788 Posts Drives: BMW 335xi coupe Join Date: Jan 2010 Location: Montreal, Canada iTrader: (0)	Doesn't seem much but dealer told me and some other users that it could lead to a problem __________________ JB4 Trebila tuned cp-e IC AMS exhaust BMS DCI AR DP's METH RB TURBO 19" VMR VB3 Stoptech BBK TC KLINE VORSHLAG SPEC STG 3 OSS design
	Appreciate 0 Quote

04-08-2012, 12:12 PM	#5
Ctm309 First Lieutenant 17 Rep 361 Posts Drives: '09 M3 AW Carbon roof DCT '11 Join Date: Oct 2009 Location: Norwalk, Ct./Port Washington, N.Y. iTrader: (7)	It seems that the collective theory is: 1% and under will not cause any problem. __________________ 2009 M3 Alpine, carbon roof, Akra slip on. 2011 335ix, Le mans Blue, Black Dakota, M-sport, PE Exhaust, VMR VB3's, ZCP 359m's, JB Stage-2, H&R Coilovers.
	Appreciate 0 Quote

04-08-2012, 05:51 PM	#6
terbow2 Private 1 Rep 58 Posts Drives: 2007 328xi Join Date: Jun 2011 Location: VA BCH iTrader: (0)	Is running 225/35/19 fronts and 265/30/19 rears to far out of rolling diameter? Was trying to get some advice before I mount the tires I have. Thank you for your help
	Appreciate 0 Quote

04-09-2012, 03:04 PM	#7
krazyking Lieutenant 17 Rep 476 Posts Drives: '08 E92 BMW 335Xi Join Date: Jan 2012 Location: Boston, MA iTrader: (3)	Hey guys, I'm planning on getting a new set of Wheels + Tires. Here is the setup I have in mind: 18x8.5 ET35 with 235/40/18 18x9.5 ET35 with 255/35/18 Can I rock the 235's in the front without a problem or would it cause a trouble with the rolling diameter? __________________ '08 E92 335Xi - Premium, Cold and Sports Packages JB4 // AFE DCI // Matte Black Grills // MTEC Angel Eyes // CF Mirror Covers // Forgestar F14's
	Appreciate 0 Quote

04-18-2012, 03:07 PM	#13
Eko Private First Class 4 Rep 103 Posts Drives: E90 335xi Join Date: May 2011 Location: Seattle iTrader: (0)	Dont some 335xi come with staggered setup stock? __________________ ----------------------------- 2008 335xi Montego Blue
	Appreciate 0 Quote

04-18-2012, 08:53 PM	#14
moveit Private 0 Rep 59 Posts Drives: 335 Join Date: Jan 2012 Location: ca iTrader: (1)	I just put staggered style 162's on my car and it seems like there is a loss of power. Should I be concerned? 225/40/18 on 8" wheels (830 rpm) 265/35/18 on 8.5" wheels (823 rpm) Tires are Potenza RE760. Difference in revs per minute is 7. How does this effect the drivetrain? Last edited by moveit; 04-18-2012 at 09:56 PM..
	Appreciate 0 Quote

04-19-2012, 10:19 AM	#17
krazyking Lieutenant 17 Rep 476 Posts Drives: '08 E92 BMW 335Xi Join Date: Jan 2012 Location: Boston, MA iTrader: (3)	Yeah it should be 255 in the rear and not 265. __________________ '08 E92 335Xi - Premium, Cold and Sports Packages JB4 // AFE DCI // Matte Black Grills // MTEC Angel Eyes // CF Mirror Covers // Forgestar F14's
	Appreciate 0 Quote

04-19-2012, 10:47 AM	#18
moonsin First Lieutenant 32 Rep 345 Posts Drives: 2021 X3 MC Join Date: Feb 2012 Location: NJ iTrader: (1)	Sooo...as long as it doesn't exceed 3 revs per mile you're okay? i'm running Hankook ventus 225/35/19 front and 265/30/19 in the rear. According to the tirerack fronts do 823 revs per mile vs. 821 for the rear (-2 difference) Last edited by moonsin; 04-19-2012 at 10:55 AM..
	Appreciate 0 Quote

04-21-2012, 04:39 PM	#21
Babydragon Captain 37 Rep 781 Posts Drives: 2007 328xi Join Date: Nov 2010 Location: Chic/ago iTrader: (0)	Ive been running 235 front and 275rear for over a year now. No problems at all, ever.
	Appreciate 0 Quote