Run flats revisited
5 miles from the dealer we hit a reasonably small pothole which immediately killed the front-right tire. Pirelli 20" run-flats.

I had planned to switch to non-runflats a while back but have been too busy/lazy. So now we are back to the dealer to get a loaner and now have two cars sitting there and have to wait to get the tires delivered which will take a couple of days.
Such a bummer, we barely have a 1000 miles on the car...
On the positive side, I was able to drive back to the dealer. On the other side, no way the non-runflats would have blown...




No road hazard as I usually swap out tires and/or wheels. The tire normally runs around $350-$400. It certainly had a short life
Last edited by Wolfman; Nov 3, 2015 at 04:42 PM.
Regarding the blowouts is it more common on wider rims (20, 21 and up) as compared to 19 inches as I think the wider the rim the thinner the sidewall width gets till it gets to be a rubber band effect?




Regarding the blowouts is it more common on wider rims (20, 21 and up) as compared to 19 inches as I think the wider the rim the thinner the sidewall width gets till it gets to be a rubber band effect?
A 20" Run Flat is much stronger than an 18" conventional tire. Which is actually not as good as there is less flexibility to adsorb a hit.
While potholes can take out any tire and rim for that matter, chances are better with a softer, more flexible tire.
Last edited by Wolfman; Nov 6, 2015 at 03:25 PM.





Instead of the Pirelli P Zero Summer Run flats, we now have Conti Extreme DWS all season tires which we need for our nasty winters. After all, this is our winter car...
What a difference the tires make!!!
Softer, more compliant ride and much quieter. More luxurious and not that
hollow sound as I had with the Pirellis.
I had the same set on the BMW and they actually get more quiet after a 1000 miles or so.
Happy
The Best of Mercedes & AMG
A 20" Run Flat is much stronger than an 18" conventional tire. Which is actually not as good as there is less flexibility to adsorb a hit.
QUOTE]
Nice to know
Thanks

Instead of the Pirelli P Zero Summer Run flats, we now have Conti Extreme DWS all season tires which we need for our nasty winters. After all, this is our winter car...
What a difference the tires make!!!
Softer, more compliant ride and much quieter. More luxurious and not that
hollow sound as I had with the Pirellis.
I had the same set on the BMW and they actually get more quiet after a 1000 miles or so.
Happy





I am surprised that so few do this. Run flats diminish the everyday driving experience for what? The potential (or occasional) benefit of having to get the tow truck instead of limping home?
The new BMW 7 series now has the option for a spare even with run flats, but according to a Bimmerfest member, the trunk space is becoming much more shallow with the spare.
Yesterday, I filled out the MB questionnaire that they sent me regarding my recent service visit. In the "additional comments" area, I mentioned the lack of a jack & spare in my car. I realize it wasn't the right venue, but to me, ANYTIME I get the chance to communicate with ANYONE from MB, whether it be at the dealer level or at MBUSA, I LAUNCH into my disappointment over the lack of a spare, and I strongly suggest that you and everyone else here do the same thing. At some point, we will be heard.
However I don't have anything else to compare it to
I'll probably switch to regular tires when these wear out. MB recommends sealant and portable air pump kit if running regular tires, but I guess a spare would be a better solution....




Here in Minneapolis, many highways with concrete pavements have grooves cut into it every couple inches to prevent surface freezing and the sound is extremely annoying with rf's.
Streamliner: I took your advice and filled out a MB survey today about a recent dealership visit, and expressed my displeasure at the RFT/no spare tire issue.




Because I could not find a spare and kept running the run flats. ( I have the 20 inch multi-spoke for the summer and 19 inch amg wheels with all weather tires for the winter)
The more reading I did on line the better I felt about the run flats. To be honest I would hate to have to change a tire on the side of the road and if I have to wait for Roadside I would rather do it at a diner or truck stop or better yet drive home.
I am sure that the conventional tires handle better than run flats but my S Class is not a race car and in my opinion my S550 with the run flats handles almost as good as my e55 in normal driving and that is good enough for me.
Some would call me stupid but I bought the tire and rim insurance and if you do not run the recommended tires you are not covered.
So I am happy with the run flats and I predict that time makers improve them in the years to come.




Expecting a luxurious ride quality equal to non-ride flats will be wishful thinking.
It's not that Mercedes suddenly switched to run flats because of some new tire technology; this is strictly done to comply with fuel consumption standards (EU/US). This is why we are cursed with the ECO start/stop as well.
It fits fine in the lower trunk space.



