Non-runflat tires with 296 wheels?

[robertrichhart]

Anybody here running 19" non-runflats with 296 wheels? Even more specifically, Yokohama s.drive tires? If so, any more cracks in the 296s after the change?

[Constant.S]

After i got rid of the RFT's i got the Continental ContiSportContact 5P and since then i never got any crack issues on the 296, its been a year since.

[09cbb]

Originally Posted by robertrichhart

Anybody here running 19" non-runflats with 296 wheels? Even more specifically, Yokohama s.drive tires? If so, any more cracks in the 296s after the change?

I switched to Conti ExtremeContact DWS. No cracks whatsoever.

[SCBMW02]

Continental extreme DWs here, no problems so far.

[evangelos]

i have my car left at the dealer waiting for the 18" 325m with non run flats... because my 296 cracked so many times that i would not dare to wear them even non-rft....

[Mr. ///M3 RD]

Originally Posted by robertrichhart

Anybody here running 19" non-runflats with 296 wheels? Even more specifically, Yokohama s.drive tires? If so, any more cracks in the 296s after the change?

Originally Posted by Constant.S

After i got rid of the RFT's i got the Continental ContiSportContact 5P and since then i never got any crack issues on the 296, its been a year since.

Originally Posted by 09cbb

I switched to Conti ExtremeContact DWS. No cracks whatsoever.

Originally Posted by SCBMW02

Continental extreme DWs here, no problems so far.

You fellows have any idea why you have no more issues? I like to know your feelings on the matter. I have my own feelings, just like to have your's (or anyones feelings for that matter) first before I share my feelings with you.

Originally Posted by evangelos

i have my car left at the dealer waiting for the 18" 325m with non run flats... because my 296 cracked so many times that i would not dare to wear them even non-rft....

I am glad your problems will be over you should be fine once you get your new wheels. I'm sure you read a few of my posts when I had my wheel crack issues.

[09cbb]

Originally Posted by Rolf-Dieter

You fellows have any idea why you have no more issues? I like to know your feelings on the matter. I have my own feelings, just like to have your's (or anyones feelings for that matter) first before I share my feelings with you.



I am glad your problems will be over you should be fine once you get your new wheels. I'm sure you read a few of my posts when I had my wheel crack issues.

Simple, the side wall of non-RFTs is much more flexible, thereby absorbing shock energy rather than fully transferring it to the admittedly weaker than normal 296 inner lip. The negative camber helps concentrate the energy on that part of the rim.

[Mr. ///M3 RD]

Originally Posted by 09cbb

Simple, the side wall of non-RFTs is much more flexible, thereby absorbing shock energy rather than fully transferring it to the admittedly weaker than normal 296 inner lip. The negative camber helps concentrate the energy on that part of the rim.

Quite so and correct ... one can almost compare it to bending a paper clip back and forth, eventually it will snap and break.

Just like with the RFT having a much stiffer side wall, along with the 2.5 degree negative camber transferring stresses into the outer diameter area of the inner lip. Even small road imperfections like uneven road surfaces (like they are on bridges and overpasses) inject stresses not to speak of potholes even the small ones. Over time the build in stresses somehow have to release and bingo we end up with first hairline cracks then the open up to wider ones causing pressure loss and flat tires.

The cracks are always in the same place and when comparing one to the other are very similar. Obviously affecting the 296 wheel much more then any other as is evident by reports on this forum.

The Z4 is a great car, I loved every minute that I owned the two I did have, unfortunately the 296 wheel was a great disappointment. The 296 wheel is just a weaker paper clip and other Styles of Z4 wheels seam to be stronger.

I am sure the manufacturer (both tire and car) know this as well, why would they keep perfecting the tire if that was not the case. Is Bridgestone not now in the third generation of the RFT? I hope the latest generation of RFT will avoid this kind of issue in the future.

[Jayda]

How long did the OEM tires last (on 19 inch wheels, style 296 wheels). Mine have about 7,000 miles on them at the moment. I'm wondering how much time I have to decide if I want to ditch the run flat tires.

[09cbb]

Originally Posted by Jayda

How long did the OEM tires last (on 19 inch wheels, style 296 wheels). Mine have about 7,000 miles on them at the moment. I'm wondering how much time I have to decide if I want to ditch the run flat tires.

I switched mine at 11,600 and didn't have a crack yet.

[jparnes1]

Originally Posted by Jayda

How long did the OEM tires last (on 19 inch wheels, style 296 wheels). Mine have about 7,000 miles on them at the moment. I'm wondering how much time I have to decide if I want to ditch the run flat tires.

I ate through mine after 11,000. I mean the rear tires were BALD. I've read where some people get between 20 and 25,000 miles. I honestly don't know how that's possible. When I get my new Z4 in April I'm immediately switching to non-RFT's, but ones with a higher treadwear rating, like Conti Extreme DW or Michelin Pilot Super Sport. Anyone want to buy the OEM RFT's????

[robertrichhart]

My OEM tires currently have 17,000 on them with what appears to be another 5,000 miles or so left on them. But, I just want them off of the 296 wheels!

[Jayda]

Originally Posted by robertrichhart

My OEM tires currently have 17,000 on them with what appears to be another 5,000 miles or so left on them. But, I just want them off of the 296 wheels!

So is that the space gray Z4 from Ohio in your avatar?

[Colorado]

My Z4 will be here in March and I will be looking into a tire swap as well. I favor Michelin or Contennial tires. Most of the time I just go to Discount tire and buy Michelin.

[Jayda]

Originally Posted by jparnes1

I ate through mine after 11,000. I mean the rear tires were BALD. I've read where some people get between 20 and 25,000 miles. I honestly don't know how that's possible. When I get my new Z4 in April I'm immediately switching to non-RFT's, but ones with a higher treadwear rating, like Conti Extreme DW or Michelin Pilot Super Sport. Anyone want to buy the OEM RFT's????

Hmmmm, get in touch with me about the tires closer to April. Do you know which manufacturer tires will be on the car? I don't know it it ever varies. My rears will go before the front.

[robertrichhart]

Yes it is..

[jparnes1]

Originally Posted by Jayda

Hmmmm, get in touch with me about the tires closer to April. Do you know which manufacturer tires will be on the car? I don't know it it ever varies. My rears will go before the front.

It's the same Bridgestones as they've always supplied.
Bridgestone Potenza RE050A I RFT
Front: 225/40R18
Rear: 255/35R18
But don't you have 19" wheels?

[BMWZ4]

jparnes, I may be interested. You are just referring to the rubber correct, and not the entire wheel & rubber? If so, I may be interested. Feel free to PM me with a price and then I will shop around and let you know.

I am in Toronto, so a drive to Rochester isn't that far. In any case, let me know what you decide.

Dave

[Jayda]

Originally Posted by jparnes1

It's the same Bridgestones as they've always supplied.
Bridgestone Potenza RE050A I RFT
Front: 225/40R18
Rear: 255/35R18
But don't you have 19" wheels?

Yes I do have 19 inch wheels, sorry I was thinking you did/will too.