E 70 Run Flat Tires
 

I did not want to hijack another thread but run flats have already come up. I wonder what brand they will be. I was on the Corvette Forum for some time and the Goodyears can run more distance on the inner tire than they state. Over 100 miles at reasonable speeds. They also have pretty good warrenty service. That said a good tire pressure system is key. Iif you do end up buying one they are expensive. I also wonder about those of us that want to run seperate winter tires. Is there a run flat winter tire? :dunno:dunno:

The current e90s have Bridgestone RFTs, and I thought I remember reading somewhere that winter RFTs are now available. Just don't know who makes them.

i have read that they are noisy and harsh. though they have been around for a bit, i feel the tech needs more oven time before i will consider them...but i still have 8 track tapes.


Mike

I drive an e90 with RFTs. They are NOT as loud as people make them out to be... I have no issues with them at all.

My guess is the Bridgestone Dueler as shown in this pic. :dunno:

Exactly. Early BMW's suffered a harsh ride with runflats because:

1) Tires were very very hard.
2) The BMW cars that wore them didn't have suspensions designed especially for them.

The E90 is the first run-flat BMW that's handling isn't overly harsh and very acceptable. Runflat tires are now softer, and the E90 suspension was designed from day 1 to accommodate run-flats...

is that the sport package rims in the pic?

These runflats are referred to a 4th generation by BMW. That means that the harshness, which has been an issue on early run-flats, is likely diminished even further than on the E90.

Bridgestone is the OE supplier for the 5, 6, 7, Z4, and E90, so it is probably a Bridgestone, and the shot of the pre-production model supports that.

Bridgestone isn't listing these tires on their website yet, which doesn't bode well. No-one needs one yet, but they are obviously a new product. With the Z4, no tire distributor had them in stock for some time after the vehicle was released, and the only place to get a replacement tire was from BMW, at BMW prices.

These tires don't have a support ring as is mentioned above. They rely on a stiff sidewall to support the vehicle. That is one reason for the special rim with the retaining lip on the inside. It doesn't require special mounting/demounting equipment, but it makes it more difficult to mount the tire due to the combination of very stiff low profile sidewall, and modified rim.

On the Z4, it is possible to mount regular (non-RFT) on the same design of rim, so I presume that will be possible with the E70 but it remains to be seen. Fitting non-RFTs is a common upgrade on the Z4 boards, but then with the very low profile and sport suspension that vehicle can be a little harsh anyways, and the tires don't help much. The X has the advantage of that 'road-hugging weight', to quote an old non-BMW advertisement. Without any real data, we are going to have to wait and see how early adopters like it. I just think that there is a potential risk for people not being able to buy a replacement; remember that after a flat, the tire usually needs to be replaced (at least if you have driven on it). The internal cracking that shows up is the sign that it can't be patched, even if the hole is in a safe part of the tread.

My unXpert 25Cts on RFs...

Picks:
-they allow Buffy and even any of us troglodytes to
"drive/get to" somewhere, for tire repair. (Assuming
you aren't 100+ miles from "repair".
-they negate the need for a jack; important in sports
cars, where space is a premium; maybe not so important
in a 5,000+ lb SUV.
-they are trendy and a necessary me-too, at least in
the minds of the car marketeers.
-they tend to ride well and are not overly "noisy", when
new or, less than half consumed.

Pans:
-Not every TarJoint can/will work on them, currently.
-Even less of those joints know what they are doing
in an R&R dismount/mount operation, espc. due to
in-wheel sensors.
-Many of your TarJoints will not have any replacement RFs,
espc. in the steam roller wheel size that tend to be fitted on
sports cars, BMWs, et al.
-That 50-100 mile "cushion" can become pretty confining
in many driving situs and many locales. Even when/if you
can get "there", points 1,2&3 come into serious play.
-No more changing a flat and just "going on"; the clock
is ticking to get that sumbitch replaced.
-In my exp., albeit with older gen RFs, they do tend
to get noisy and "hard" around post-3/4s+ of tire tread life
use.
-BringMoneyWith you for a new tar or, a new set.

But, whatchagonnado...it's progress. :confused:
BR,mD

then one could agree it is a matter of personal taste and tolerance. btw i have no real issue with them either, merely sharing what i have read about them. on cars without spares, then they are the obvious choice.


Mike

Exactly. And all this so that there can be a 3rd row seat.

I would consider removing them, going to non-RFTs, and carrying a repair kit like the M has. Goop and a compressor, in a nice carry bag with a roundel.

Exactly!:) What is wrong with using those kits?:thumbup: Why RFT?:confused: Am I missing something?
RFTs have way tooooooooooo many negatives! The major one for me is not having choices (tire & rim), specially at those sizes on a dare I say SUV! I am not just talking about brand but also types. Also, of course cost for two(?) new tires and FEDEX air delivery(?) every time there is a puncture.:rofl:
Does any one know whether one can use non-RFTs on these rims without any kind of draw back?

You may also get the repair kit with the RFT. My friend's M3 had RFT plus the repair kit.

Just curious...can RFT be patched at a tire joint if you get a nail puncture, etc?

See post #8, above.

The BMW description of the rim in the press release is the same as for the Z4, it isn't a standard rim but rather has a hump to hold the bead in place when deflated. It is a common mod on a Z4 to put standard tires on. I haven't done it yet, don't like throwing away 4 tires with 12,000 km and lots of tread left, but if I keep that car the replacements will not be RFTs.

My bet is that it will be possible to change to standard tires, but there will be no place to carry a spare or a flat tire without folding down at least one row of seats.

EDIT: perusing other (Non-USA) press releases, I see that at least in Australia, BMW has decided that an emergency spare (read space-saver temporary) will be included with all five-passenger E70s. That is good news for some of us, and also tells those not lucky enough to be in Australia that a space-saver tire fits under the floor where the 3rd row seat would have gone.

Usually if you haven't driven on it, ie it went down while parked, then yes. If you drove on it (as it was designed for) then the tire can exhibit cracks on the inside of the casing from flexing. If the cracks are there, it isn't safe to fix. It also doesn't still have its speed rating. No doubt some tire shops will fix them, but the SOP is to buy a new tire, and to buy two tires if the other tire on that axle is worn past a certain tread depth. $$$.

I have been driving a Sienna minivan with RFTs for just over 3 years. We are about to replace our second set of tires at 44,000 miles. The first set of 4 tires ran us over $1k at 21,000 miles. A new set will run $700.

The tires are Bridgestone B380s. They suck! But they are better than the Dunlops that were the other OEM pick. People were lucky to get 15k miles out of the that tire.

Toyota has since had to settle a Class Action on these tires, which resulted in them sending us a check for our inital out of pocket tire replacement costs. But it isn't just the money or the horrible and uneven tread wear. These tires are hard to get, and your average tire shop doesn't know how to deal with RFTs and tire pressure monitoring systems. $tealers mark up these costs because they have you by the balls. Tire Rack cannot keep the tires in stock, and when they do have them, they are VERY expensive.

I have hated every minute of the RFTs and would be VERY wary of ever owning another car with them. Just read through the reviews othe Bridgestone B380s on Tire Rack. You will see one disgusted customer review after another. Don't even bother with the forums at SiennaClub.org. It is too depressing. :(

Yes, RFTs CAN be patched as long as the patch is in the middle of the treads, say, for a nail.

Run Flats
 

Seems like the practical solution is to wait until they need replacement and convert to standard tires and carry a repair kit. Those that opt for larger wheels and have snow in winter have to have a winter tire option.
Seems odd for a SAV to worry about being off the beaten path as if you get a tire problem you are pretty much screwed. I get run flats for a sports car but a SAV or SUV seems odd. I will see have the dealer explains it.

If Im not mistaken, for the e90's, BMW offered a RF protection plan thingy for the life of the warranty for a lot less than most thought...I think it's like 500 bucks or something..:dunno:...They came out and replaced them, or you could go to the nearest place that had them and BMW would take care of it...One flat, and it would be paid for...

If "by off the beaten path" you mean down a backroad or on a trail, then runflats are actually an advantage. You can always drive home, because they are designed to run flat.

If you mean in a rural area, away from tire stores, then I agree. However, that is why you have BMW Roadside service, they will pick up the car and haul it to a dealer for you.

Up and down I-5 in the west is not a concern. In June I was driving Yellowstone and Jackson Hole. I would need to count on roadside assistance as I saw no RFT there. Even with roadside asistance it still could be time for someone to get to you. I assume not many X5 really get far off road. The XC90 and MDX both have 3rd row seating but as far as I know no RFT. If you do not opt for third row seating I wonder if a temp spare is an option. It seems like for some countires it may be.

Otherwise there is nothing about the E70 that I dislike.