E90 LCI 335i M-Sport tyre pressures

ss134 · 06-20-2009, 04:27 PM

Hi,
My LCI E90 335i M Sports steering feels very light at speed and the car tends to 'bounce' over small bumps in the road resulting in the car not feeling planted on the road. Im convinced its the tyre pressures. Im on michellin Front= 225/40ZR18 88Y and Rear255/35ZR18 90Y. The sticker inside my door says 2.3Bar (33.5PSI) front and 2.7Bar (39PSI) rear. Ive played around with the pressures and have found a huge difference in steering feel and the 'bounce' issue depending on what pressures im running. The upshot is that 2.3/2.7 just doesnt feel right.
Anyone with the same tyres on M Sport suspension who could advise on what theyre running on their car would be greatly appreciated. What does the manual in the US recommend for these tyres on M Sport??
Also any tyre experts who could offer some pros and cons of different pressures on RFT- your advise would be welcome.

Thanks.

Mk23 · 06-20-2009, 04:39 PM

Quote:

Originally Posted by ss134

Hi,
My LCI E90 335i M Sports steering feels very light at speed and the car tends to 'bounce' over small bumps in the road resulting in the car not feeling planted on the road. Im convinced its the tyre pressures. Im on michellin Front= 225/40ZR18 88Y and Rear255/35ZR18 90Y. The sticker inside my door says 2.3Bar (33.5PSI) front and 2.7Bar (39PSI) rear. Ive played around with the pressures and have found a huge difference in steering feel and the 'bounce' issue depending on what pressures im running. The upshot is that 2.3/2.7 just doesnt feel right.
Anyone with the same tyres on M Sport suspension who could advise on what theyre running on their car would be greatly appreciated. What does the manual in the US recommend for these tyres on M Sport??
Also any tyre experts who could offer some pros and cons of different pressures on RFT- your advise would be welcome.

Thanks.

The US ones say 32PSI Front, 36PSI Rear. But this is a known issue with RFT to feel like the traction is being lost over potholes and bumps. I wouldn't mind some pros and cons of higher or lower pressures myself, maybe I can find my perfect pressure as well.

ss134 · 06-20-2009, 05:00 PM

Quote:

Originally Posted by Mk335i

The US ones say 32PSI Front, 36PSI Rear. But this is a known issue with RFT to feel like the traction is being lost over potholes and bumps. I wouldn't mind some pros and cons of higher or lower pressures myself, maybe I can find my perfect pressure as well.

Are those pressures with M Sport suspension? If so i wonder why theyre different to UK spec cars???

cstavaru · 06-20-2009, 05:03 PM

I use 2.5 bar on front and 3 bar on rear (the recommended pressure) on my 335i e90 LCI M Sport, but I have 17" wheels (225 on front and 255 back). The car is running fine.

ss134 · 06-20-2009, 05:16 PM

Anyone with M sport suspension on 18s?

Raikkonen · 06-20-2009, 08:12 PM

Our Sport and M Sport suspensions are the same in the North American Market. Our recommended sport package 18" diameter pressures are 33 front and 41 rear (for speeds up to 100mph). These are the pressures listed on the door and in the manual.

I'm running Michelin run-flats on mine that are set to factory pressure and the ride is great. Excellent even. Compared to my Bridgestones on my old 2007 335, these are AS GOOD as non run flats!

carrabassett786 · 06-20-2009, 09:00 PM

my fatty 325xi still jumps over the gutters on bridges, it freaks me out. I think its just the fact that the car isn't 3 tons like my old truck, though.

ss134 · 06-21-2009, 08:09 AM

Quote:

Originally Posted by Raikkonen

Our Sport and M Sport suspensions are the same in the North American Market. Our recommended sport package 18" diameter pressures are 33 front and 41 rear (for speeds up to 100mph). These are the pressures listed on the door and in the manual.

I'm running Michelin run-flats on mine that are set to factory pressure and the ride is great. Excellent even. Compared to my Bridgestones on my old 2007 335, these are AS GOOD as non run flats!

Thanks for the reply- at speeds of upto 100mph i dont have a problem. I don't have the pressures for over 100mph. A lot of my driving is on the Autobahn and there is no mention in my manual or in my door so im guessing at the moment which isnt good. Does you manual give pressures for 100mph + ?

noro · 06-21-2009, 08:51 AM

Keep in mind BMW's recommended number aren't necessarily the best ones for YOU. They are the best settings for the AVERAGE driver.

I would
a) Keep the pressure the same around the 4 corners to achieve maximum balance for the car.
b) Play around with the setting until you find a good compromise. Anything below 32-33 you start adding the risk of getting your rims bent.

In terms of actual performance (not comfort) you can use one of those laser thermometers and measure the heat level across the tire after a long highway drive. The idea is that the middle of the tire has to be in the middle of the inner and outer sides (temperature).

Raikkonen · 06-21-2009, 06:32 PM

According to my owners manual:

Over 100 mph for the 335 w/ factory sport package, 1 driver + 3 passengers maximum, and 18 inch rims:

W rated tire (speeds up to 167 mph) F - 36 psi R - 41 psi

Y rated tire (speeds up to 186 mph) F - 32 psi R - 36 psi

06-20-2009, 04:27 PM	#1
ss134 Brigadier General 230 Rep 3,899 Posts Drives: F80 M3 Join Date: Feb 2009 Location: Germany/UK iTrader: (1)	E90 LCI 335i M-Sport tyre pressures Hi, My LCI E90 335i M Sports steering feels very light at speed and the car tends to 'bounce' over small bumps in the road resulting in the car not feeling planted on the road. Im convinced its the tyre pressures. Im on michellin Front= 225/40ZR18 88Y and Rear255/35ZR18 90Y. The sticker inside my door says 2.3Bar (33.5PSI) front and 2.7Bar (39PSI) rear. Ive played around with the pressures and have found a huge difference in steering feel and the 'bounce' issue depending on what pressures im running. The upshot is that 2.3/2.7 just doesnt feel right. Anyone with the same tyres on M Sport suspension who could advise on what theyre running on their car would be greatly appreciated. What does the manual in the US recommend for these tyres on M Sport?? Also any tyre experts who could offer some pros and cons of different pressures on RFT- your advise would be welcome. Thanks.
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06-20-2009, 05:03 PM	#4
cstavaru Brigadier General 313 Rep 3,262 Posts Drives: 2009 335i M Sport Sedan 6MT Join Date: Aug 2008 Location: Bucharest, Romania iTrader: (0)	I use 2.5 bar on front and 3 bar on rear (the recommended pressure) on my 335i e90 LCI M Sport, but I have 17" wheels (225 on front and 255 back). The car is running fine. __________________ Mods(click): Cobb + RB Turbos \| Aquamist HFS-4 Meth \| Drexler LSD \| Bilstein B12 Pro-Kit \| Custom K&N Apollo Intake \| Wagner Intercooler \| Macht Schnell Downpipes \| BMW Performance Power Kit \| BMW Performance Exhaust \| BMW Performance Short Shifter \| M3 Subframe Bushings \|
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06-20-2009, 05:16 PM	#5
ss134 Brigadier General 230 Rep 3,899 Posts Drives: F80 M3 Join Date: Feb 2009 Location: Germany/UK iTrader: (1)	Anyone with M sport suspension on 18s?
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06-20-2009, 08:12 PM	#6
Raikkonen Captain 339 Rep 820 Posts Drives: 2024 X5 M60i Join Date: Jun 2005 Location: Grosse Pointe Park, MI iTrader: (2)	Our Sport and M Sport suspensions are the same in the North American Market. Our recommended sport package 18" diameter pressures are 33 front and 41 rear (for speeds up to 100mph). These are the pressures listed on the door and in the manual. I'm running Michelin run-flats on mine that are set to factory pressure and the ride is great. Excellent even. Compared to my Bridgestones on my old 2007 335, these are AS GOOD as non run flats! Attached Images Last edited by Raikkonen; 06-20-2009 at 08:19 PM.. Reason: left out info.
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06-20-2009, 09:00 PM	#7
carrabassett786 Lieutenant 13 Rep 508 Posts Drives: 11 328i Join Date: Dec 2006 Location: Ponte Vedra Beach, FL iTrader: (0)	my fatty 325xi still jumps over the gutters on bridges, it freaks me out. I think its just the fact that the car isn't 3 tons like my old truck, though. __________________ E90 328i Space Gray/Chestnut ZMP 2MF ZP2 ZV2 ZCV ZCW-washers HK SAT 3rd Pedal ED 2011.10.10 E90 325xi BSM/Terra ZSP ZPP ZCW Adaptive Xenons SAT 3rd pedal Gone E53 X5 3.0i Black Sapphire/Truffle ZPP ZCW ZRC Xenon Nav
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06-21-2009, 08:51 AM	#9
noro Colonel 90 Rep 2,707 Posts Drives: '91 M3, '04 E46 ZHP, '72 2002 Join Date: Aug 2006 Location: Boston iTrader: (0)	Keep in mind BMW's recommended number aren't necessarily the best ones for YOU. They are the best settings for the AVERAGE driver. I would a) Keep the pressure the same around the 4 corners to achieve maximum balance for the car. b) Play around with the setting until you find a good compromise. Anything below 32-33 you start adding the risk of getting your rims bent. In terms of actual performance (not comfort) you can use one of those laser thermometers and measure the heat level across the tire after a long highway drive. The idea is that the middle of the tire has to be in the middle of the inner and outer sides (temperature). __________________ zhpregistry.net - ZHP stats and free classifieds.
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06-21-2009, 06:32 PM	#10
Raikkonen Captain 339 Rep 820 Posts Drives: 2024 X5 M60i Join Date: Jun 2005 Location: Grosse Pointe Park, MI iTrader: (2)	According to my owners manual: Over 100 mph for the 335 w/ factory sport package, 1 driver + 3 passengers maximum, and 18 inch rims: W rated tire (speeds up to 167 mph) F - 36 psi R - 41 psi Y rated tire (speeds up to 186 mph) F - 32 psi R - 36 psi
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