One thing that might be worth trying before dismissing RFTs is to get the wheel alignment laser checked.
Had this done recently and it's like driving a totally different car. Like it's on non-RFTs. It really is that different.
I can imagine RFTs being a lot more sensitive to correct alignment which would explain it.

 

I don't know the exact makeup of the sidewalls in RFT's but I do know (being a polymer chemist in a previous "life") that the lower the temperature, the firmer rubber becomes. It will want to hold onto its shape that little bit longer on a cold morning (assuming there's more rubber in the sidewall of an RFT) therefore the part of the tyre in contact with the road where parked will remain slightly compressed and flattened for a while. I think!

I got RFT's coming on my 520, whoopee.....

Cheers,

Ian.

 

What is your definition of a cold morning? Do you notice the difference at a certain temperature? Do you park your car outside or in a warm garage at night?

 

+1 I have not had a flat tire in 33 years of driving. In the 12 months I have had RFT I have had two nails in the tyres and have not been able to repair them but have had to replace them!

 

Wow, thanks for all the replies!! Ok...

I park outside. The temp is around 35 - 45 F. I used to notice flat spots on military Hummer bias ply tires REALLY bad in winter. Yes, the runflats DO have thicker sidewalls, that is how they are able to support the vehicle weight with no air.

The fact that they are low profile means that they will warm up faster (not as much rubber to heat up), but I don't remember ever feeling flat spots on regular radial tires on any other car I have ever driven. I'm guessing that the thicker sidewalls on the runflats are the cause of the vibration (very, very slight) that I'm feeling. I am kind of sensitive to vibrations in my car because of my last vehilce which would rattle your teeth out around 55 mph. Never could find the cause of that vibration... Anyway, I just wanted to find out if it was due to the runflats or if I might have a tire out of balance (the dealer just replaced all 4 tires and I would assume that they would have balanced them). I may have thrown a weight too, I don't know. I am taking it in for an alignment and I was going to have them balance the tires again ($$), but I wanted to find out if anyone else has noticed this quirk before I pay for nothing.

Thanks!!!!

 

My tyre is punctured now, I got the warning light yesterday. I have just put a new set of runflats on the car 2 months ago. The tyre place tells me that they are refusing to plug my runflat and want me to buy a new one for E250. I knew I should have replaced run flats with non runflats when I had the chance

 

I too have flat-spot tires first thing after the car sits for >8 hours. Temperature doesn't seem to matter either. It goes away after about 1 mile or so, not a big deal. I agree that it's not run-flats that cause this flat-spotting. I low profile 18" on my 911 and they do the same thing.

I have Sports Package with 18" Dunlops RFT tires. I can't wait for these tires to wear out...I hate them. They are noisy and the ride is harsh.

 

So the consensus is that pretty much all low profile tires will do this. Cool. I can live with that. I was just hoping that I didn't have something else wrong with my new used car. I only have about 6K left on the warranty and I am trying to take care of EVERYTHING I can find before that warranty runs out. Thanks for the help!!!

 

try another garage....

whne my car showed low pressure, i took it to a tyre dealer, asking for it to be repaired as it had a slow leak. no arguments, they looked at it. It was actually a bad seal to the rim - remounting the tyre cured it.

 

Must say that when I got my first nail, I took it to Dunlop and my BMW SA, both refused to repair it or try to repair it. Just quoted the book says .....

Then took it to a local independent tyre retailer and they did repair it for me. But the repair did not stick. The book was right.