When I first heard about the concept of run-flats I was very excited and positive about it.
The added safety, security and convenience seemed like such a great development in car design.
I still think that the concept is a great one BUT ... the trade-off in ride quality and in some cases handling just isn't one I'm happy to accept.

Either the technology hasn't been perfected yet and we are just suffering the pain typical of early adaptors OR the technology is fundamentally flawed and will never work. I don't know how it will pan out in the next few years. I would prefer to see run flats improved to a point that they are as good as (or better than) normal tyres. I want to have them...

In the meanwhile though, I just want BMW to give me a choice when I order the car from the factory.
If some customers want a car with normal tyres they should be allowed to order one (with whatever suspension settings are compatible with that setup). If some customers want the RF setup and can live with the trade-offs, they should be able to order that (again with whatever suspension tuning needs to be done to that configuration).

 

It's obvious BS. Why tell you in one breath that the systems have been hardened to cope with the extra jarring and then tell you the suspension's been softened to compensate for the tyres?

I've got an E61 with Dynamic Drive (standardish springs - trick anti-roll bars) on 17" wheels. The Bridgestone RFs ruined the car. Their only upside for me is super-sharp steering response because there is so little flex in the sidewall. Everything else is rubbish for the same reason. Since I've replaced them the car's stopped tramlining (so bad it was almost dangerous), it's much quieter and the ride is better because every small pimple and ripple is not transmitted any more. To my mind handling and grip are well up anything I want on a public road. If you want to go on a track you'd need different tyres/wheels/suspension anyway. Let's not forget it's a four seater car and it has to cope with a wide range of demands on its suspension.

I know it's tempting fate to say it, but I must have done close to a million miles driving and I've never had a catastrophic tyre failure and I don't know anyone who has. What clinched the change for me was when I had a slow puncture in one of the RFs and I tried to get a repair/replacement. No-one would repair it (against company regulations) or could get a replacement quickly. This means that there's a good chance that your runflat will let you get to a tyre dealer or BM dealer and then what? Wait a few days for it to be sorted? Not much good if you're 200 miles from home. What the hell is wrong with a full size spare?

 

Tried to fit one in the donut recess??

ABC

 

You're safe! M-models would never handle so sweetly with RF's...

 

Not even room for a space-saver?

 

Nope...

If you ditch run-flats the only practical option is to carry a can a tyreweld, a portable compressor and a mobile phone to call the flatbed rescue truck (when the tyre weld just doesn't cut it). Some people are carrying a spare and a jack strapped down in the boot but that doesn't leave much room for luggage! And... if you dump your run-flats and get a puncture BMW assist won't help you out of it...

Not a pretty picture...

 

Yeah I did. It doesn't work without removing all the processor and relays and putting them somewhere else. That's beyond me but not BMW. Take all that out and it's deep enough to take a wheel. I just had to make do with a spacesaver.

 

:thumbsdown:

 

 

Next question is.........how many of you would buy the F10 if it comes only with runflats and no room for any kind of spare?

I my case, no chance, unless they improve RFT's a hell of a lot in the next 3 years.

A puncture on a RFT with a full load of passengers + luggage, no spare and I can only drive it 30 Miles??

That my friends is not progress.