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[Wingman335]

I am still having issues understanding the advantage non RFT has over RFT. I apologize beforehand for this statement, because I have no professional driving experience... so my post might be ignorant.

I have RFTs on my current vehicle (2011, E92 335i). I was absolutely sure that I would change the tires to non RFT right after getting the vehicle, based on the forum threads.

However, after driving for two months, I really don't feel any harshness on the ride quality. I know a friend of mine who has a 2009 E92 335i with non RFTs. He replaced it because he claims the ride is much better with non RFTs. I drove his vehicle, and then mine over the same stretch of partially damaged road in Houston. Quite frankly, I couldn't tell the difference between either of them. The ride comfort felt the same.

So, is the difference between RFT and non RFT so minute, that only the most discerning driver would notice? I surely don't notice a difference, and I have honestly tried! As I mentioned earlier, might it be because I am not a "pro" driver? I have not had any track experience.

[pruettfan]

Originally Posted by Wingman335

I am still having issues understanding the advantage non RFT has over RFT. I apologize beforehand for this statement, because I have no professional driving experience... so my post might be ignorant.

I have RFTs on my current vehicle (2011, E92 335i). I was absolutely sure that I would change the tires to non RFT right after getting the vehicle, based on the forum threads.

However, after driving for two months, I really don't feel any harshness on the ride quality. I know a friend of mine who has a 2009 E92 335i with non RFTs. He replaced it because he claims the ride is much better with non RFTs. I drove his vehicle, and then mine over the same stretch of partially damaged road in Houston. Quite frankly, I couldn't tell the difference between either of them. The ride comfort felt the same.

So, is the difference between RFT and non RFT so minute, that only the most discerning driver would notice? I surely don't notice a difference, and I have honestly tried! As I mentioned earlier, might it be because I am not a "pro" driver? I have not had any track experience.

I am going to guess you have Michelin PS2 RFT's. They are much better than the Bridgestones which have a harsh ride, cost a fortune and have a shorter treadlife then any other tire I can find on the market. The Michelin tires are much better. I have friends who have C6 Corvettes that track them. First thing they do is dump the goodyear RFT's. Some have gone to the Michelin and have had good results. Where most folks have complaints about RFT's however is on regular streets where you have railroad tracks and potholes not at the track where few ever go.

[HighlandPete]

Some of us have experience of the early RFT fitments, where BMW were clearly not on top of the game. Later models have improved, but I'm personally still not convinced, even on the latest F10/11 5-series, that all the negatives are yet sorted. There have to be compromises for the concept to be even considered, let alone work. BMW engineers must have been pulling their hair out over the years, and the M Division has in a way clearly indicated where tire technology still lay, for performance driving.

Personally I hate the way the RFT feeds back some very weird sensations, not totally predictable and unsettle the dynamics of the vehicle on typical roads we drive. I would rather have a little less turn in, in exchange for a surefooted driving experience.

Here in the UK we know BMW haven't had a properly tuned sport suspension system for our UK roads for several years now. It's guys like Kevin Bird, (linked in another post) who talk so much sense for sporty road driving.

BTW, Lotus can design a decent sport comfort/handling package, perhaps BMW engineers can still learn a thing or two.

HighlandPete

[cb1111]

Originally Posted by Wingman335

I am still having issues understanding the advantage non RFT has over RFT. I apologize beforehand for this statement, because I have no professional driving experience... so my post might be ignorant.

I have RFTs on my current vehicle (2011, E92 335i). I was absolutely sure that I would change the tires to non RFT right after getting the vehicle, based on the forum threads.

However, after driving for two months, I really don't feel any harshness on the ride quality. I know a friend of mine who has a 2009 E92 335i with non RFTs. He replaced it because he claims the ride is much better with non RFTs. I drove his vehicle, and then mine over the same stretch of partially damaged road in Houston. Quite frankly, I couldn't tell the difference between either of them. The ride comfort felt the same.

So, is the difference between RFT and non RFT so minute, that only the most discerning driver would notice? I surely don't notice a difference, and I have honestly tried! As I mentioned earlier, might it be because I am not a "pro" driver? I have not had any track experience.

It depends on a large part on the conditions of your roads. Many here on the board have been drinking the "I hate RFT" kool-aid and hate them with a passion - even though most couldn't come up with a logical reason if their life depended on it.

Like others have said, the Michelin RFTs are worlds better than the Bridgestones in tread life and the sidewalls seem a bit softer as well. RFTs work great in Germany where the roads are smooth.

[cb1111]

Originally Posted by HighlandPete

Here in the UK we know BMW haven't had a properly tuned sport suspension system for our UK roads for several years now...
HighlandPete

The same holds true for the US. But that doesn't mean that the RFTs aren't designed as an integral part of the suspension system - even if done badly.

[Tag]

Originally Posted by cb1111

Many here on the board have been drinking the "I hate RFT" kool-aid and hate them with a passion - even though most couldn't come up with a logical reason if their life depended on it.

That's a biased statement. Here's some logical reasons for you. I have non-RFT's and my car outperforms the RFT's, tires cost less, don't have the sidewall bubble issues and even though I went up one size from stock setup my ride is far more comfortable. If you prefer RFT's that's fine, but don't knock them because others don't.

[captainaudio]

Originally Posted by tag824

That's a biased statement. Here's some logical reasons for you. I have non-RFT's and my car outperforms the RFT's, tires cost less, don't have the sidewall bubble issues and even though I went up one size from stock setup my ride is far more comfortable. If you prefer RFT's that's fine, but don't knock them because others don't.

+1

I came to my own conclusions with the RFTs which were not at all suited to the roads in the Northeast.

Most of the people who post that they have no issue with the ride quality of RFTs live in areas where the roads are in relatively good shape. I can tell you from personal experience that driving on RFTs in South Florida and driving on them in New York City are two very different experiences.

As far as I am concerned other than the run flat capability RFTs are inferior to regular tires in every respect. They will probably improve but I think BMW started using them before they were ready for prime time.

CA

[cb1111]

Originally Posted by tag824

That's a biased statement. Here's some logical reasons for you. I have non-RFT's and my car outperforms the RFT's, tires cost less, don't have the sidewall bubble issues and even though I went up one size from stock setup my ride is far more comfortable. If you prefer RFT's that's fine, but don't knock them because others don't.

At the risk of getting you annoyed - there is no possible way that you can determine if one tire "outperforms" another - nobody here drives the cars anywhere near their limits.

The sidewall bubbles is not a RFT issue but is prevalent on low profile tires on cars with stiffer suspensions driving on bad roads. Go to any R32 forum and you'll see many complaints of sidewall bubbles - all blamed on the non-RFTs.

Are non-RFTs more pliant and provide a softer ride? Sure, but BMW designed the cars that use RFTs for RFTs. Swapping them out changes the intended characteristics of the suspension system.

Can you swap them out and get a softer ride? Sure, but don't be a lemming and jump on the "I hate RFT" bandwagon without thinking for yourself.

[cb1111]

Originally Posted by captainaudio

+1

I came to my own conclusions with the RFTs which were not at all suited to the roads in the Northeast.

Most of the people who post that they have no issue with the ride quality of RFTs live in areas where the roads are in relatively good shape. I can tell you from personal experience that driving on RFTs in South Florida and driving on them in New York City are two very different experiences.

As far as I am concerned other than the run flat capability RFTs are inferior to regular tires in every respect. They will probably improve but I think BMW started using them before they were ready for prime time.

CA

I agree that the entire suspension design of any sports oriented car is unsuited for Northeast roads. I'd go so far as to say that the only vehicles suited for NYC roads are those with tank treads as they can't be easily swallowed by the potholes from hell.

I'd opine that the proper tire for a BMW in NYC is a 12" wheel with a 195/85/12 tire. That'll give you an extra 2 1/2 to 3 inches of extra sidewall to absorb the shock.

Getting back to topic.

The BMW was not designed for NYC streets. Non-RFTs will not fix that. Perhaps a non-sport suspension would help too.

Bashing RFTs because the tires in your locale are crappy makes little sense.

[HighlandPete]

Originally Posted by cb1111

Are non-RFTs more pliant and provide a softer ride? Sure, but BMW designed the cars that use RFTs for RFTs. Swapping them out changes the intended characteristics of the suspension system.

This is the issue... are the cars designed for RFTs, (in a complete and stand alone sense), or have they been compromised for RFTs?

From the very beginning of RFTs, some BMW models have had an option to have RFTs or not, without the suspension being modified. We can still do it on the UK configurator, spec' up and opt for the RFT upgrade on some models. The suspension parts carry the same numbers when we can check out model variants. So we are not getting a true picture of how the cars are designed for the RFT, in particular. Even changing wheel rim/tire sizes changes a car's dynamics, so BMW are not too concerned when some models can have 16" - 19" wheels on the same vehicle, purely selected as the customer's choice.

I'd agree the later models do appear to have softer setups and that needs to be considered, when selecting alternative tire specifications.

HighlandPete

[cssnms]

Originally Posted by cb1111

RFTs have stiffer sidewalls. A stiffer sidewall improves turn-in and handling. The BMW suspension is calibrated for that.

Swapping out for non RFTs will certainly improve ride as you get softer sidewalls - but you also compromise the intended handling of the car.

Sports cars have a harsher ride because of the stiffer suspension systems (that RFTs are part of) so don't try to convince yourself that switching to non RFTs is a good thing for handling - even if it is good for ride.

Originally Posted by cb1111

there is no possible way that you can determine if one tire "outperforms" another - nobody here drives the cars anywhere near their limits.

[cssnms]

BMW installs different brands and sizes of RFT's (depending on wheel choice and location) and sells their cars this way all over the world. The suspension system is engineered to provide the best all around performance while being used as a daily driver. In addition, the suspension must have a tolerance to be able to accomodate both high and low profile tires which allows the customer to select from the various wheel/tire options offered by BMW without creating a ride that will loosen fillings.

To suggest that BMW engineers specifically designed the suspension of the cars around a RFT without considering the other obvious factors (rating, size etc) is rediculous esp considering all of the wheel/tire options that are available for customers to select from. Furthermore, and to my point above, not all tires are created equal (RFT's too) and because of that it would not only be cost prohibitive, but inefficient to design the suspension for each car around the handling characteristics of a particular tire. BMW engineers selected run-flats for one reason and one reason only, because the car is designed in such a way it will not accomodate a spare tire, not because BMW engineer's believed RFT somehow offer superior handling characteristics. Generally speaking RFT's are inferior in almost every category.

If one person believes their RFT's will actually improve the handling characteristics of their car over a non-rft performance tire let them go on thinking that, but the truth lies where the rubber meets the road.

[captainaudio]

Originally Posted by cb1111

I
Bashing RFTs because the tires in your locale are crappy makes little sense.

Saying that there is no issue with them because they are not a problem for you drive makes even less.


I am driving on public roads in the Northeast corridor, the most densely populated area of the United States and a huge market for BMW. It is not like I am driving the car on unpaved logging roads. I have had "Pothole Explosions" in New York, Connecticut, Pennsylvania, Vermont, on Interstates and on rural New England roads. The sport suspension is standard on the E92. I find it a bit of a stretch to accept that BMW is selling a car that is not supposed to be driven in the Northeast United States.

FWIW I solved the issue by replacing the RFTs and replacing the OEM shocks with KONI FSDs. The car still has a firm ride (which I have no issue with) but the harshness, Pothole Explosions and loss of contact on rough surfaces are gone.

CA

[captainaudio]

Originally Posted by cssnms

If one person believes their RFT's will actually improve the handling characteristics of their car over a performance tire let them go on thinking that, but the truth lies where the rubber meets the road.

Or fails to.

CA

[cb1111]

Originally Posted by captainaudio

Saying that there is no issue with them because they are not a problem for you drive makes even less.


I am driving on public roads in the Northeast corridor, the most densely populated area of the United States and a huge market for BMW. It is not like I am driving the car on unpaved logging roads. I have had "Pothole Explosions" in New York, Connecticut, Pennsylvania, Vermont, on Interstates and on rural New England roads.

FWIW I solved the issue by replacing the RFTs and replacing the OEM shocks with KONI FSDs. The car still has a firm ride (which I have no issue with) but the harshness, Pothole Explosions and loss of contact on rough surfaces are gone.

CA

You're right. BMW should stop selling the 3 series in the Northeast - or develop a "NYC edition" with marshmallows instead of springs and these tires

[captainaudio]

Originally Posted by cb1111

At the risk of getting you annoyed - there is no possible way that you can determine if one tire "outperforms" another - nobody here drives the cars anywhere near their limits.

The sidewall bubbles is not a RFT issue but is prevalent on low profile tires on cars with stiffer suspensions driving on bad roads. Go to any R32 forum and you'll see many complaints of sidewall bubbles - all blamed on the non-RFTs.

Are non-RFTs more pliant and provide a softer ride? Sure, but BMW designed the cars that use RFTs for RFTs. Swapping them out changes the intended characteristics of the suspension system.

Can you swap them out and get a softer ride? Sure, but don't be a lemming and jump on the "I hate RFT" bandwagon without thinking for yourself.

So let me see if I have this straight.

The RFTs should not be replaced because the car was designed for them and performance of the car will be compromised but since nobody here is driving the car close to the limits we are not going to be able to tell that the performance has been compromised.

Makes perfect sense!

CA

[cb1111]

Originally Posted by captainaudio

So let me see if I have this straight.

The RFTs should not be replaced because the car was designed for them and performance of the car will be compromised but since nobody here is driving the car close to the limits we are not going to be able to tell that the performance has been compromised.

Makes perfect sense!

CA

There you go putting words into my mouth.

I didn't say that they shouldn't be replaced - just that they shouldn't be replaced because you are a sheep and have jumped on the bandwagon without thought - and without considering that the car was designed for RFTs.

Don't go to non-RFTs just because it is the "in" thing to do. It is disgusting to hear everyone dump on RFTs without considering the fact that they are perfectly comfortable and well suited to the car in many locales. Just because NYC isn't the place to drive a 3 series with sport suspension and RFTs doesn't mean that that combo isn't perfectly fine for Florida, California or most of Europe.

Newsflash - Europe apparently has that problem too as evidenced by this photo



Remember that if your car is leased you'll need RFTs on turn in as well.

[captainaudio]

Originally Posted by cb1111

There you go putting words into my mouth.

I didn't say that they shouldn't be replaced - just that they shouldn't be replaced because you are a sheep and have jumped on the bandwagon without thought - and without considering that the car was designed for RFTs.

Don't go to non-RFTs just because it is the "in" thing to do. It is disgusting to hear everyone dump on RFTs without considering the fact that they are perfectly comfortable and well suited to the car in many locales. Just because NYC isn't the place to drive a 3 series with sport suspension and RFTs doesn't mean that that combo isn't perfectly fine for Florida, California or most of Europe.


Remember that if your car is leased you'll need RFTs on turn in as well.

My car is not leased. I paid cash for it so I don't have to worry about returning it with RFTs.

As I have stated here before I think the RFTs are fine in Florida. I purchased my car in Palm Beach Florida and drove it there for serveral weeks and several thousand miles before shipping it to NYC. I had no issue with the RFTs in Florida and had I kept the car there I probably would have kept them.

I agree with your "If it ain't broke don't fix it" attitude and would not suggest that anyone who does not have an issue with RFTs change them just for no particular reason. Regardless of what the suspension was designed for I did not experience any loss of performance after changing out the shocks and the tires. I was able to try the various combinations at the limits as I have access to a track, a skid pad and an autocross course. Before I changed anything out I consulted several friends who are professionals that have a lot of experience setting up suspensions for both the road and the track. I did not change anything unless I had done extensive research and had talked to exerienced drivers who had driven cars that had the same modifications.

I am very happy with the results.


CA

[cb1111]

Originally Posted by captainaudio

...I agree with your "If it ain't broke don't fix it" attitude and would not suggest that anyone who does not have an issue with RFTs change them...

CA

See, that wasn't so hard, was it?

I'm just trying to get people to think before they blindly spend money on mods without understanding why the manufacturer (BMW, Audi, Toyota, Yugo etc) did what they did and what the possible consequences are.

For you, swapping suspensions and tires was probably a logical move - but not for everyone. You're also smart enough to have done your research beforehand and didn't just echo "RFTs bad, normal tires good."

[Tag]

Originally Posted by cb1111

At the risk of getting you annoyed - there is no possible way that you can determine if one tire "outperforms" another - nobody here drives the cars anywhere near their limits.

Again you paint a blanket statement. How do you know how well my car handled before and after? How do you know if I push my car to its limit or not? As I stated before it handles better. How do I know this? Simple, I can go around the same turn at a much faster speed without the tire breaking traction, less hop and obvious increased confidence.

Originally Posted by cb1111

Are non-RFTs more pliant and provide a softer ride? Sure, but BMW designed the cars that use RFTs for RFTs. Swapping them out changes the intended characteristics of the suspension system.

Can you swap them out and get a softer ride? Sure, but don't be a lemming and jump on the "I hate RFT" bandwagon without thinking for yourself.

You obviously don't understand how suspension works. Just because you can gain a more softer ride does not mean your performance will suffer. Too harsh and you're not planted as much as you should be and also get wheel hop, too soft and you get that floaty feeling. IMO the ZSP suspension coupled with RFT is too harsh and bouncy on an uneven road.

Summer tires are not sponges, they have stiffer sidewalls, that's the nature of a performance tire. You can let the air out of a summer tire completely and you'll still be about an inch off the ground they are so stiff. Also as I stated before I run a +1 size and because my sidewalls are shorter its a bit stiffer yet it handles better and rides nicer. Not to mention non-RFT weigh less and you can fill them up more or less with air to get the best overall ride whereas RFT's are harsh at almost any PSI.

It's easy to be the naysayer but also easy to be wrong.

[captainaudio]

Originally Posted by cb1111

See, that wasn't so hard, was it?

I'm just trying to get people to think before they blindly spend money on mods without understanding why the manufacturer (BMW, Audi, Toyota, Yugo etc) did what they did and what the possible consequences are.

For you, swapping suspensions and tires was probably a logical move - but not for everyone. You're also smart enough to have done your research beforehand and didn't just echo "RFTs bad, normal tires good."

Frankly I was blindsided by the ride quality issue. I test drove an identical car to tje one I ordered in Northern New Jersey over roads that I thought were poor (little did I know) and after taking delivery on my car I drove it in South Florida for 2,000 miles. The ride was firm, as I expected on a performance oriented car, but not harsh when driven in those environments.

When I started driving my car in the Tri-State area (NY, NJ, CT.) I was very surprised at how unsuited the suspension and tires were to poor surfaces. Having people tell me that I had purchased the wrong car was of no help. I already had the car. I was looking for a solution to the issue and after many months of frustration I was able to come up with one.

CA

[Mr. ///M3 RD]

Originally Posted by cb4

Unfortunately engineers are not the people making the decisions to put RFTs on these cars.

+1

I so agree ...

In my humble opinion it is the Accountants that are now in charge like in so many US companies ... Engineers used to be in charge today it is all about money.

Someone said ... the M cars have no RFT that is correct, they will never have RFT as long as Engineers are in charge at the M Devision

BMW made a grave mistake by adding a RFT that is designed in Italy to German specifications and then manufactured in Japan. I am talking about the Bridgestone RFT that now apparently is better, I am talking about Generation III, you and I have Generation I or II on our cars we are the Ginny Pigs the latest and greatest Bridgestone Generation III apparently is much improved, noise wise, handling wise, cooling wise (it has cooling fins I wonder why). Problem is this latest Generation III is only available in Japan and no one including our friends here at Tire Rack can tell us when it might be available in North America. Go figure.

Meanwhile I think BMW is loosing a lot of loyal Customers. Why they don't give the Customer a choice of Non-RFT or RFT it would be so simple. Most Customers get rid of the RFT and carry a bad taste in there mouth (so to speak) against BMW for outfitting a fine car with inferior tires. Mind you RFT is something new I know and once properly developed will help to maintain safety. Meanwhile it is a pain in the A.s as many of us know, replacements hard to find, very costly etc. etc.