Run Flat tires vs Normal tires - dealer cut away carcus...

[Dackelone]

Last week when i was over at that fabulous German delaer in Sinsheim... IanC asked me IF I had any side profile photos of a RFT vs a Normal tire carcus. In my haste to take pics of all the great cars on display there... I had forgoten to take a side profile pic of the RFT.

Today I was over at my local German dealer... and they had that same display from BMW. Showing a regular tire vs a RFT. I came with my camera ready! The RFT is so much more reinforced and stiffer then a normal tire. Enjoy the pics.


Normal tire is on the LEFT, Run Flat Tire is on the RIGHT!






Normal tire left RFT right...






RFT...





RFT on the bottom...






RFT on the bottom...





RFT on the bottom...





RFT on the bottom...






I gotta say I know everyone here seems to dislike the OE RFT... but I realy like them. Atleast on the glass sooth roads over here in Germany.

[Dackelone]

I think these photos might be easier to look at...

RFT is on the RIGHT(I stand corrected! )...

RFT on RIGHT side...

RFT on bottom...

[Lowest_Frequency]

Interesting stuff, however your second post says the first picture has RFT on the left when your first post says its on the right. Might want to double check those.

[Dackelone]

Originally Posted by Lowest_Frequency

Interesting stuff, however your second post says the first picture has RFT on the left when your first post says its on the right. Might want to double check those.

Thanks for pointing that out! I corrected it. The RFT are on the right side in my photos. You can tell a RFT bc the side wall and thread surface is so much thicker than a normal tire. The RFT also have very little "flex" in it vs a normal tire.

[ianc]

Thanks alot for the pics David!

The difference is very clear! The soft factory suspension was developed for these very hard tires, so now that I've upgraded the suspension, I've been thinking about changing out the tires. Just hesitating a little before pulling the $650 trigger...

Thanks again!

ianc

[ptack]

It's why we call them run craps.

[Trier Germany]

Silky smooth roads in Germany? I must be in the wrong part of germany i need to go check out bamberg

[bavarian19]

I still dislike BMW's decision to ditch the spare. I don't mind RF tires. Personally, I like going without. But even with them, you are much more limited because of a lack of a spare.

[zoom335is]

The concept of the RFT is great but if its going to be thicker then they need to develop a more flexible compound to bring it back on par with normal tires but naturally not in a way that would make the structure weaker.

I like that BMW got rid of the spare, no wasted space, no extra tire changing gear, less weight, I approve. In the 10 years I have been driving I have gotten maybe 4 flat tires, not bad. I have not experience enough flat tired to need the RTF's or even a spare. Even if I do, I just use BMW services, get my car taken to a dealer, replace tire, on my way. My 335is came with summer "sport" RTF's but will not replace them until they are worn, but I will grab non RTF winter tires and when time comes non RTF summer tires.

[kinan_sleiman2006]

I prefer a normal high speed tire because run flat tire makes the riding much firmer..

[Oulixes]

Thanks, Dackelone - the photographs demonstrate quite well how the tires work.

[_dopehead_]

so thats why my car felt like a bouncy castle going over even small potholes before i changed them to non-runcraps :-)

[Dackelone]

Originally Posted by Trier Germany

Silky smooth roads in Germany? I must be in the wrong part of germany i need to go check out bamberg

The roads in Bayern (Bavaria) are taken care of very well! I notice this all the time when I travel to other parts of DE. Bayern does have some places that need repair... but it seems to me that Bayern is just more serious about putting road repair at a higher priority. Even the Autobahn Meister's seem to drive the newest trucks and have those cool new LED road construction signs. These are the new digital moving signs.

Like in Hessen they don't even cut down the grass that grows next to the BundesStrasse (back roads). The autobahns have to deal with a lot of city traffic. Taking care of the raods there, seems to get put on the back burner.

In Baden Württemberg the raods are decent but there are many places where the road should be closed and repaired but is not. The (lower part) A7 and A81 are places that come to my mind.

The the former DDR lands... the autobahns are all brand new now... it is just the(DDR) drivers you need to worry about! And the back roads (Bundes Strasse) are really old and dangerous.

When I was in Rheinland-Pfalz (like when I went to the 'Ring a few weeks ago) I also noticed the Autobahns and Bundes Strasse were not in tip top shape like mine over here in Bayern.

These are just my thoughts. But I did see this article in last Friday's AutoBild. I will post it bellow.

[WilliamE92]

Well this explains why the RFT's ride like wagon wheels on bad roads....

[BrokenVert]

DAYM!

[vase330]

Over here in the people republic of [Insert State here] we have man sized pot holes all over the place. The roads are worse than in some 3rd world countries. So no the runflats are no good here. In fact when you have a puncture, it usually of the blowout type that renders run flats useless. I now tote a spare around and wish my car came sans this crap. I have since bought real tires. They bubble a lot less easily too copared to the expensive OEM runcraps.

[zoom335is]

Originally Posted by Oulixes

Thanks, Dackelone - the photographs demonstrate quite well how the tires work.

I agree, this pics are great, clear and simple images of RTF's.

[335iTrace]

I just called my dealer and asked what the penilty was for not having run flats when i turned the car back in (lease) $250! so its worth just getting them so i dont have to pay that... i was going to get VMR's and swap them back when it was time to turn it back in... damn it!

[michifan]

I'm a fan of run flats as well. They are safer and weigh less (including spare delete). The ride is firm, but I'm kinda used to that kind of ride.

Personally, I'd be willing to bet that 90% of the people that think they hate them wouldn't know the difference on regular roads without knowing that they were running run flats vs regular tires.

Nobody argues that run flats make bad track tires, but most guys I know have track specific tires anyway.

[Zell]

Though they make a harsher ride, I think the added safety of them is very nice.

[Raine]

They're pretty harsh.

[captainaudio]

Originally Posted by michifan

I'm a fan of run flats as well. They are safer and weigh less (including spare delete). The ride is firm, but I'm kinda used to that kind of ride.

Personally, I'd be willing to bet that 90% of the people that think they hate them wouldn't know the difference on regular roads without knowing that they were running run flats vs regular tires.

Nobody argues that run flats make bad track tires, but most guys I know have track specific tires anyway.

The ride quality of the RFTs is very dependent on the quality of the roads they are driven on. They are very bad at handling bad road surfaces and on bumpy curves they are just plain scary as the bounce around so much that the contact patches loose contact with the road surface and the rear end want to step out. I have named this phenomenon CTO (Crappy Tire Oversteer)

Drive both RFTs and non-RFTS in NYC and the difference in ride quality is very obvious to both the driver and the passengers.

When I bought the 335i I had never been on a BMW Forum and had no idea that the RFTs were controversial. I purchased the car in Palm Beach and had no issue with the RFTs in 2,000 miles of driving in South Florida.

After a month I shipped the car to NYC. It was unbearable. I was so bummed out that I decided to sell the car in spite of the fact that it was less than 2 months old. I discovered this forum, expressed my concerns and someone here suggested I get rid of the RFTs. I got rid of them and never looked back.

RFTS are a good idea but they are not ready for Prime Time.





CA