Has anyone dumped his/hers runflats on 20s?

[CS6913]

Originally Posted by art4.8i

i doubt it, as long as you go with the same load index or higher, it should be fine. with yokohamas, it states specifically that the sidewall is reinforced for a more precise steering (the load index on the yoko's is 110 vs 106 on the stock dunlops. Additionally, they have a Y speed rating, which means that the tire can go up to 300 km/h. so, i don't think the handling will be wishy-washy.

+ 1

[scoobydoo]

The only two advantages or rfts are being able to drive on with a puncture and slightly sharper initial turn-in due to the stiffer sidewalls. Everything else about them is crap. The difference when I swapped them for regulars on my 535d was like night and day. I am seriously contemplating getting rid of the two little seats in my E70 in order to put a spare there. If I do that once I have finished the OEM 20s would buy regulars. My winter setup is 19s (212) with non runflats anyway.

[X5Jay]

Originally Posted by oredart

Are you concerned about losing control of the vehicle at 75mph? It's my understanding (correct me if I'm wrong) that the RFTs remain structurally intact enough to mitigate any sort of rollover or other catastrophic movement by the vehicle when there's a blow-out at a high rate of speed.

If this is a concern, then everyone who drives a vehicle with non-RFs should worry about this - and that's a huge majority of the vehicles on the road today. Not a very sound argument...

[oredart]

I see that the RFTs are a matter of convienence not safety. My argument was based on a factor of safety. Thanks to all for the insights.

[TexasBMW]

So how was it at 145? Can't wait to get there myself when I take delivery!

Originally Posted by art4.8i

dont get me wrong, i have driven 145 mph on my 20' dunlop runflats, but I think there are better tires than dunlop sport maxx RFT. plus, my front ones are almost gone at 11K miles. (that's an inconvenience) besides i have no problem switching to regular tires since I have a spare tire.

[art4.8i]

Originally Posted by TexasBMW

So how was it at 145? Can't wait to get there myself when I take delivery!

it was effortless. the X felt very composed and safe. However, at such speeds, wind noise becomes quite apparent and a little bit annoying. Otherwise, it was perfect!

[art4.8i]

Sorry to bring an old thread back!

But, after having switched, last Spring, to Michelin Latitudes Tour HP for my 20", I have decided to switch back to my Dunlops (Which are in my garage still). Let me explain why:

At first, when I had them put on, I noticed an immediate improvement in ride comfort. However, after having driven it aggressively, i must say that they are no good for the X's capabilities. The steering feels a lot lighter, the on-center feel is not the same, and you have to give more steering effort to turn. The DSC seem to kick in a lot more therefore constraining the power delivery. Even on even surfaces, if I floored it and tried to change lanes at the same time, the DSC would engage and not allow for any acceleration. Needless to say, you can forget about even increasing speed while taking those long-turn on-ramps, as DSC would prevent the fun yet again. I was thinking that maybe the DSC software could be upgraded, but no luck with that. I also played with the tire pressure, but no improvement.

I also noticed that the Michelins are rather noisy on concrete highways: all other surfaces seemed very quiet.

Additionally, they are not as wide as the 214 style wheels, which makes the X look less aggressive.

Anyway, sorry for a long write-up, but I really thought somebody may benefit from this.

I must say, that after almost 7K miles, the Michelins look like new.

Does anybody have any thoughts or other experiences?

Thanks

[y5choi]

When I read your initial post, I kind of suspected that you have an aggressive driving style- that will let the fronts run down pretty quickly.

Anyway, I agree with you that the Dunlops are the best when it comes to performance and cornering- Tirerack.com did a short test on performance runflats and the sports Maxx came out on top

http://www.tirerack.com/tires/tests/...ay.jsp?ttid=59

I currently have 20" summers and 18" winters (both Dunlop ROFs from BMW) and I do feel that the 20" lack tread depth and longevity- but I can't deny the safety and performance aspect of the tires.

If I wanted a plush comfy ride, I would not even look at BMWs anymore- I'd opt for a big Escalade or a Merc GL.

Happy driving

[soldmystang]

while i have 19's i was planning on going to the non-runflat Michelin HPs. did you install runflats or non-runflats?

the non-RFs are ten pounds lighter in the 19" size. that is a ton of unsprung weight difference. i wonder if that contributes to the change in handling? it concerns me the DSC kicks in so easily. were you sliding the tires or was it wheel spin?

the Bridgestone RFs i currently have are wearing well. i should get 30k miles out of them.

[art4.8i]

Originally Posted by soldmystang

while i have 19's i was planning on going to the non-runflat Michelin HPs. did you install runflats or non-runflats?

the non-RFs are ten pounds lighter in the 19" size. that is a ton of unsprung weight difference. i wonder if that contributes to the change in handling? it concerns me the DSC kicks in so easily. were you sliding the tires or was it wheel spin?

the Bridgestone RFs i currently have are wearing well. i should get 30k miles out of them.

They are non runflats. It is difficult to say whether it was wheel spin or sliding because the DSC would engage so early.