Bimmerfest - BMW Forums

Bimmerfest - BMW Forums (http://www.bimmerfest.com/forums/index.php)
-   7 Series - F01 / F02 (2009 - current) (http://www.bimmerfest.com/forums/forumdisplay.php?f=143)
-   -   How much quieter without runflats? (http://www.bimmerfest.com/forums/showthread.php?t=667613)

october 01-02-2013 06:58 PM

How much quieter without runflats?
 
I just picked up a new 740Li and noticed much more road noise on coarser roads than my previous 750Li (E66). Thinking about getting rid of the runflats and switching to regular tires. Can I expect a quieter ride and what brand tire should I get? Currently have 20" M sport wheels. Is the F01/02 quieter with regular tires compared to the E65/66? Thanks.

csmeance 01-02-2013 09:10 PM

It really depends on what sort of noise you are hearing. If it's wind noise then you won't have a change with the tires, however if it's a constant hum or drumming sound then the tires will have a large impact.

As well you will have a large impact in the comfort of your ride; you won't feel smaller bumps and things as much.

My recommendation would be a Continental DW (summer tire) or a Continental DWS (all season) if it comes in your size. If not, then the Pirelli PZero Nero (all season) are great tires!

jprescott 01-05-2013 04:38 PM

My biggest gripe moving from an S550 to a 740 Li was road noise. I eventually figured out it was the run flats causing vibration and road noise. After much web surfing and soul searching I put on non run flats and keep an inflation kit in the car. World of difference. It will blow your mind to feel and hear the difference. What was BMW thinking? The sales guys always say every one is moving to run flats. Not true. We are looking at a GL 450 vs Ml 350 and MB is not going that way. It destroys the "luxury car" feel

october 01-05-2013 05:49 PM

Any suggestions as to a good non RFT that would be siginificantly quieter than my current Pirellis PZero's? Since I have 20" M Sport wheels, my choices are more limited than 19's.

azbimmer 01-05-2013 06:59 PM

Quote:

Originally Posted by october (Post 7292655)
Any suggestions as to a good non RFT that would be siginificantly quieter than my current Pirellis PZero's? Since I have 20" M Sport wheels, my choices are more limited than 19's.

I ditched my run flats and replaced them with Conti DWS. A world of difference in handling and quiet.

BMW has it all wrong, when it comes to tires, and this is the reason my next car will not be a BMW.

chrischeung 01-05-2013 08:58 PM

Quote:

Originally Posted by azbimmer (Post 7292774)
BMW has it all wrong, when it comes to tires, and this is the reason my next car will not be a BMW.

Is that fact or opinion? Why would they stick to RFT in that case? If the cons outweigh the pros, why do it?

That's what always troubles me. I don't dispute that RFT are probably quieter and ride better, but I feel that BMW has put a lot of engineering and testing into tuning their cars suspension and tires together, and by making a change, I'm circumventing that effort. I'm saying that my expertise is better than theirs.

I just can't say that I do have that expertise, experience, or resource to out do them. Yes there may be specific instances and geographies where other tires are better, but my opinion is that everything taken as a whole, BMW has optimized, as best they can with the time and resources at hand, their suspension and tires the way they want their car to ride, handle, perform etc.

Cdnrockies 01-05-2013 09:27 PM

Quote:

Originally Posted by chrischeung (Post 7292972)
Is that fact or opinion? Why would they stick to RFT in that case? If the cons outweigh the pros, why do it?

That's what always troubles me. I don't dispute that RFT are probably quieter and ride better, but I feel that BMW has put a lot of engineering and testing into tuning their cars suspension and tires together, and by making a change, I'm circumventing that effort. I'm saying that my expertise is better than theirs.

I just can't say that I do have that expertise, experience, or resource to out do them. Yes there may be specific instances and geographies where other tires are better, but my opinion is that everything taken as a whole, BMW has optimized, as best they can with the time and resources at hand, their suspension and tires the way they want their car to ride, handle, perform etc.

Please go explain your rationalization to Porsche who refuses to put RFT's on any of their vehicles.....all of which outperform every BMW. ;)

chrischeung 01-05-2013 09:33 PM

Quote:

Originally Posted by Cdnrockies (Post 7293026)
Please go explain your rationalization to Porsche who refuses to put RFT's on any of their vehicles.....all of which outperform every BMW. ;)

You misunderstand me. Forget RFT.

Say Porsche optimized their suspension to work with a Bridgestone ABC tire. You go and fit a Firestone XYZ tire since you think it is better. You have just said overridden the effort that Porsche has put into tuning their car. I'm just saying that I personally don't think I am better than BMW engineering. I'm not saying that Porsche engineering, if given a BMW car, couldn't make it better - non RFT, different springs, etc.

But I haven't seen anyone better than a BMW engineer say another tire is overall better than the OEM BMW fitment for a BMW. Have you seen someone at Porsche say that putting a non-RFT on a BMW will make it overall better than BMW wants? Even better - is there a BMW engineer saying we tried A, B and C tires, while A was better, we went with C, due to costs, supplier relationships etc.

I'm just putting RFT into the same bucket as things like aftermarket chips, air filters, wheels, sound systems, aero aids etc. I personally go with what auto manufacturers put into their cars. I generally would not upgrade my BMW, Porsche, Benz etc. with anything that is aftermarket since I don't GENERALLY feel that those companies have as comprehensive the resources as auto manufacturers. I'd feel differently if someone or some entity out there with more expertise than BMW, who did more development on a BMW, recommended something differently.

If I bought a car without RFTs as OEM, I wouldn't change them to RFTs. If BMW went back to non-RFTs, I'd go with non-RFTs.

Cdnrockies 01-05-2013 09:55 PM

Quote:

Originally Posted by chrischeung (Post 7293032)
I'm just putting RFT into the same bucket as things like aftermarket chips, air filters, wheels, sound systems, aero aids etc. I personally go with what auto manufacturers put into their cars. I generally would not upgrade my BMW, Porsche, Benz etc. with anything that is aftermarket since I don't GENERALLY feel that those companies have as comprehensive the resources as auto manufacturers.

This last part of your quote helped me to better understand what you were getting at. ;)

I still don't share your viewpoint as many brands, including BMW, put adequate tires on their cars when there are better options out there. IF BMW truly cared about performance and suspension set up to correspond, they would be putting better tires on their best performance car, the M3. You can find multiple threads on multiple forums about how much better the car handles/laps if the owners swap out to PS2's vs. the original Bridgestones or Dunlops.

RFT's have improved immensely since they debuted, but they are not in any way better than conventional tires when it comes to road noise or performance.

P.S. Our X5 handles significantly better and is much quieter after dumping the OEM RFT's and putting on the Conti DWS's. ;)

chrischeung 01-05-2013 10:06 PM

Quote:

Originally Posted by Cdnrockies (Post 7293067)
Our X5 handles significantly better and is much quieter after dumping the OEM RFT's and putting on the Conti DWS's. ;)

How much better? How much quieter? Did you put it on a skid pan? Run lap times? Use a decibel meter? Scientific or subjective measures? How many miles of varying roads and areas did you compare the two against? Different temperatures? Inflation pressures?

My idea being that you may have made a decision say on 5 criteria. Whereas BMW made a choice based on 100 criteria. I see it in my work everyday, where someone says that you should have done this - but they often don't consider 5 other things that would be adversely affected by that 1 choice.

ChrisF01 01-05-2013 10:13 PM

Quote:

Originally Posted by Cdnrockies (Post 7293067)
This last part of your quote helped me to better understand what you were getting at. ;)

I still don't share your viewpoint as many brands, including BMW, put adequate tires on their cars when there are better options out there. IF BMW truly cared about performance and suspension set up to correspond, they would be putting better tires on their best performance car, the M3. You can find multiple threads on multiple forums about how much better the car handles/laps if the owners swap out to PS2's vs. the original Bridgestones or Dunlops.

RFT's have improved immensely since they debuted, but they are not in any way better than conventional tires when it comes to road noise or performance.

P.S. Our X5 handles significantly better and is much quieter after dumping the OEM RFT's and putting on the Conti DWS's. ;)

I just wonder what major kickback (and it has to be pretty major, for them to even stick them down Rolls Royce's throats) that they receive from pushing run-flats on their cars. Personally I believe it's either the bean-counters, or the marketing arm that was able to push them.

I would never, ever buy RFTs to replace non-RFTs. I have AAA, and I have never been stranded by a flat regular tire before. Not to mention I'm less susceptible to potholes and road hazards than RFTs are...

smashhell 01-05-2013 10:15 PM

I'm sure BMW is listening.
Just look at F10 5 series.
All of them have runflats standard.
People were complaining like crazy.
Than when M5 comes along, they ditched run flats. Not only that but they shoved some Michelin Pilot Super Sports on that car.

chrischeung 01-05-2013 10:18 PM

Did M cars ever run RFTs? I don't think they did (not sure about the E60). This also goes to my point - where BMW feels that there is a better OVERALL tire, RFT or non-RFT, all things considered, they will choose the better tire. They are non exclusively RFT married.

It doesn't make sense otherwise. Yes, non-RFTs are better for M's, so let's go with them. Non-RFTs are better for non-Ms, so let's not go with them, and use RFTs instead. Everything that I know about BMW (and Germans as a culture), is that they are logical - sort of the Vulcans of earth. But as we know, that can also work against them when they are wrong - they'll be more stubborn. Example in point - iDrive. Panned by almost everyone. But they stubbornly have stuck with it. iDrive still hasn't been adopted by Porsche.

Emilner 01-06-2013 11:50 AM

Quote:

Originally Posted by chrischeung (Post 7293106)
Did M cars ever run RFTs? I don't think they did (not sure about the E60). This also goes to my point - where BMW feels that there is a better OVERALL tire, RFT or non-RFT, all things considered, they will choose the better tire. They are non exclusively RFT married.

It doesn't make sense otherwise. Yes, non-RFTs are better for M's, so let's go with them. Non-RFTs are better for non-Ms, so let's not go with them, and use RFTs instead. Everything that I know about BMW (and Germans as a culture), is that they are logical - sort of the Vulcans of earth. But as we know, that can also work against them when they are wrong - they'll be more stubborn. Example in point - iDrive. Panned by almost everyone. But they stubbornly have stuck with it. iDrive still hasn't been adopted by Porsche.

I have seen dozens if not hundreds of people who converted to non rfts on their BMWs. Every. Single. Person. Says it dramatically improves the car. It rides quieter, is smoother and performs better. Every single person without one exception.

The reason M cars come with non-rfts? Rfts are one big bag of compromise. They ride harder, noisier and have less grip than conventional tires.

Why is BMW committed to rfts? I have no idea. Why do they make you pull the door handle twice to leave the car, or press the stop button twice to stop the car????

Leslierc 01-06-2013 12:02 PM

BMW does not equip M cars with run flats.

Emilner 01-06-2013 12:07 PM

Quote:

Originally Posted by Leslierc (Post 7294033)
BMW does not equip M cars with run flats.

Yep, that's what I said. They do it for a reason. Rfts are just one hodge podge of compromises.

azbimmer 01-06-2013 02:51 PM

Quote:

Originally Posted by chrischeung (Post 7293106)
Did M cars ever run RFTs? I don't think they did (not sure about the E60). This also goes to my point - where BMW feels that there is a better OVERALL tire, RFT or non-RFT, all things considered, they will choose the better tire. They are non exclusively RFT married.

It doesn't make sense otherwise. Yes, non-RFTs are better for M's, so let's go with them. Non-RFTs are better for non-Ms, so let's not go with them, and use RFTs instead. Everything that I know about BMW (and Germans as a culture), is that they are logical - sort of the Vulcans of earth. But as we know, that can also work against them when they are wrong - they'll be more stubborn. Example in point - iDrive. Panned by almost everyone. But they stubbornly have stuck with it. iDrive still hasn't been adopted by Porsche.

I think you need to understand the rationale car makers use when making these decisions. The M cars are high performance cars, and BMW will never put RFTs on them. All other BMW models have moved to RFTs because of reduced cost of putting a spare, and reduced weight leading to better mileage numbers. Car making, like any other engineering effort, is full of compromises between cost, performance, reliability etc. Do not take a manufacturer's decision like the gospel truth.

Honda had tried moving to Run flats earlier, but backed off because of the additional cost of fixing the tires and general displeasure of its customers. Mercedes, Audi and Porsche, all equivalent, or better in performance to BMW depending on model or options, have never put RFTs on their cars.

It is one thing to like the brands we buy. It is quite another to put blind faith in the brand. be a smart consumer, and shop around. That is what free market is all about.
Good luck!

chrischeung 01-06-2013 03:37 PM

Quote:

Originally Posted by Emilner (Post 7294015)
They ride harder, noisier and have less grip than conventional tires.

Can someone explain one thing to me. Say run flats ride harder. That means they are stiffer. Say you go to non-RFTs. They are softer. Won't that mean that your turn in won't be as crisp, since the tire is softer? Not talking about grip, which I know is lower for run flats, but for turn in response. I've never seen that discussed (seen ride, grip).

chrischeung 01-06-2013 03:44 PM

Quote:

Originally Posted by azbimmer (Post 7294427)
It is quite another to put blind faith in the brand. be a smart consumer, and shop around

I would. But I'm not going to put my faith in posts from Bimmerfest that rely on unscientific seat of the pants, based on decisions they already made (as if you would usually criticize a personal purchase). Can someone point to objective tests from magazines, or perhaps things like tirerack.com that are comprehensive? Road, track time tests, various conditions, etc.

Another that always gets me is this - folks say yes, I got a better ride, road holding noise etc. on non-RFTs. But are those that important? What else did they do to their cars beyond that? Did they add sound insulation? Go to slicks? Replace springs and shocks? Put in a LSD?

Why would they just say, yep - ditched the RFTs, now the car is perfect. It always feels like the action has more to do than what they desired. Because if they really cared about those things ,wouldn't they take further action? I personally am an example of that. I say I do care about ride - but I got the 20" wheels. But if I really cared about ride, wouldn't I just stick with the 19s? So I see a lot of folks say they care about ride, but they get the biggest rims, and sport suspension.

ChrisF01 01-06-2013 04:25 PM

Quote:

Originally Posted by chrischeung (Post 7294555)
Can someone explain one thing to me. Say run flats ride harder. That means they are stiffer. Say you go to non-RFTs. They are softer. Won't that mean that your turn in won't be as crisp, since the tire is softer? Not talking about grip, which I know is lower for run flats, but for turn in response. I've never seen that discussed (seen ride, grip).

I think they're referring to the sidewalls being much harder, which transfers that roughness to the ride comfort. I don't think it has much to do with the actual tire tread (grip). Like Emilner said, they're a huge bag of compromises. They're main focus is the advancement of the silly technology that is run-flats. Like any supplier they can only invest so much time/effort into a project. So they divert a chunk of time and energy away from better grip into more advanced run flats.

At least that is how I take all this...

jprescott 01-06-2013 05:04 PM

I see comments about Vulcan logic and science around here. Is it possible that BMW has gone this way in the spirit of money and not engineering? As a professional who deals with the drug company machine I say " science schmiance". There is probably an economic advantage to BMW. As stated above ALL of us who have gone non run flat have noticed a HUGE difference. I do not have the ability to test this with decibel meters etc. Just subjective like every one else's comments.

chrischeung 01-06-2013 08:15 PM

Quote:

Originally Posted by jprescott (Post 7294740)
Is it possible that BMW has gone this way in the spirit of money and not engineering?.

I would doubt that. Because if that was the case why wouldn't others like Toyota do it? Tire manufacturers could probably lower costs if MORE companies used the tires. BMW is the only one concerned about money? I honestly think it costs BMW more to fit run flats than not. Again, nothing concrete, but if run flats are more as replacements, are they not more as originals? The other thing is, does this really hurt BMW? Lower sales? Lower JD Power sat scores?

One thing I could see happening, is that they may think that the technology is getting better, and they already have committed significant time and resources to this path - they hope that the gap will close quickly enough before it really impacts sales. It may be more costly to go back to non-RFTs. They would have to equip their cars with space saver storage etc. That is likely only possible with a new or major redesign. Sort of like how iDrive worked out - initially poor, but with development, it became acceptable.

dbs600 01-06-2013 08:30 PM

Quote:

Originally Posted by azbimmer (Post 7294427)
All other BMW models have moved to RFTs because of reduced cost of putting a spare, and reduced weight leading to better mileage numbers.

Proverbial nail hit on its head, sadly.

chrischeung 01-06-2013 08:40 PM

Question - does anyone here live in an area that has good roads? Do they have problems with run flats? I'm wondering if that is an issue. I live in North Dallas, and the roads here are excellent (I mainly take the DNT/121 when going on the freeways), likely the best I've ever seen in the USA. It's almost as good as Germany. But I also didn't mind the Bridgestone RFTs on 18s when I was in Northern California with my E60 535i.

I was in South Florida over Christmas, and the rental 300C's ride quality on South Florida roads (thinking I95) was noticeably worse than my 750 with RFTs on 20s in North Dallas.

azbimmer 01-07-2013 05:45 AM

Quote:

Originally Posted by chrischeung (Post 7295203)
Question - does anyone here live in an area that has good roads? Do they have problems with run flats? I'm wondering if that is an issue. I live in North Dallas, and the roads here are excellent (I mainly take the DNT/121 when going on the freeways), likely the best I've ever seen in the USA. It's almost as good as Germany. But I also didn't mind the Bridgestone RFTs on 18s when I was in Northern California with my E60 535i.

I was in South Florida over Christmas, and the rental 300C's ride quality on South Florida roads (thinking I95) was noticeably worse than my 750 with RFTs on 20s in North Dallas.

You have way too much free time on your hands. On the one hand, you say you want to take the manufacturer's design decision as the Gospel (or Vulcan) Truth. Then you go ahead and change the OEM Rims to 20". How's that for consistency?

And since you are so biased against standard tires, why waste everyone's time with posts against Non RFTs?


All times are GMT -7. The time now is 02:45 PM.

Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
© 2001-2011 performanceIX, Inc. All Rights Reserved .: guidelines .:. privacy .:. terms