I know this topic has been addressed many times. I previously owned a Lexus SC430 that had factory run flats. The car was obviously much different handling than my P car but I just saw that the new Corvette has run flats, rear tire is 325/30 Eagle F1 .....................Would run flats on my 19" S wheels make a huge difference in handling? I sure do like the added comfort knowing I won't likely get stranded due to a flat.................

 

i heard RF and regular tires are vastly different feels. i drove a bmw 3 and 1 series with RF. they feel pretty decent to me actually. maybe the suspension is tuned specifically for RF? i heard people reporting the switch from RF to regular makes handling better though.

 

The C6 Vette has now the Michelin PS2 ZP, which is better than the GY F1. I suspect though that the std PS2 is better than the PS2 ZP, but for street use may not be that different, as the PS2 sidewall is already quite stiff.

 

nope.....new Corvette Grand Sport..$75,000.here is tire info:

Like all recent Corvettes, the 19-inch rear wheels are an inch larger than the fronts, while the slim, five-spoke design is unique to the GS. Rather than rolling on the standard painted wheels, our tester came equipped with the chromed versions, which are a bit too bling for our tastes. Thankfully, there's a third option: a sinister set of dark gray competitions wheels inspired by the C6.R. Yes, please.

On the topic of tires and wheels, while we expect most Corvette owners to hand-wash their rides, sometimes you just don't have the time or inclination. Unfortunately, the 12-inch wide, P325/30ZR19 Eagle F1 Supercar run-flats mounted on the rear simply don't fit through the guide tracks of most automatic car washes. In a vain attempt to run the GS through our local auto-wash to prep it for a photo shoot and check for leaks, the 275 mm front rubber barely fit, so we backed out and gave it a proper bath at home.

 

Forget what GM mounts on the GS. Look at what is mounted on the ZR1 - Michelin PS2 ZP...

 

I know that I am in a small minority, but I like this topic. My other cars are BMW's and I do like riding on my run flats in those cars. My Carrera will be due for new tires soon. I will look and see what run flats may be available, consider any size differences, then determine if it is a viable alternative.

I do carry a spare and I would like my trunk back.

 

Take it from a guy with (bad) experience with RF tires...keep what the factory gave you and designed the car to use. Porsche avoids the RF tire for probably very good reasons. I had problems with (admittedly first-generation RF's) chunking of the tread at approx 18K and a huge amount of interior road noise in a C5 Corvette. With my C6, while the tread chunking did not appear, the ever-increasing road noise again became an annoyance. In both instances I replaced the RF tires with conventional tires and never had a problem. The regular tires wore better, lasted longer, rode smoother, were quieter throughout their life-span, and handled, in my opinion, a touch better than the RF's. As long as we have tire pressure monitoring systems (and we pay attention and check it now and then) the only advantage the RF tire presents is the ability to well, run flat. If getting stuck in the middle of nowhere is your concern, get familiar with a tire plugging kit and buy a better air pump to fix a flat until you can get to a place to properly repair or replace your damaged tire.

 

Based on my experience with runflats, I plan to stay away from them. My BMW 535 is my daily driver and has normal all season tires and the ride is quite good ( handling is also quite good). I had been given loaner cars from BMW when my car was being repaired. The 3 series cars with normal suspension and tires were extremely harsh when encountering minor pavement breaks on the interstate. In some cases it was so bad I thought I had bent a rim and crashing noise from the suspension sounded awful. These same sections of pavement would yield mere thumps with my 535. These runflats cannot be good for a car. I am sure that runflats will imprve but for now, I will avoid any car ( purchase) that has them. This means no more BMW 3 or 5 series in the future for me.

 

Sure, tell yourself that - I did - and lived it. Now I am no longer suffering from the "I'll fix it and get back on the road" delusion. Sidewall damage will strand you. I carry a spare now.

I had run-flats on my BMW 550i and the tires were fine - no odd wear or abnormal noise. They were Dunlop or Bridgestone - maybe. The handling was also quite good on mountain twisties.

 

I've read all the threads discussing the added security of carrying a spare, and while I can certainly see the value in doing so, I still can't help but wonder what you're going to do if a back tire goes flat while you're out with the little lady on a weekend trip (meaning you have a couple over nighters stored behind you).

You take the space-saver spare out of the frunk, swap it out with the flat rear, then what do you do with the rear wheel & flat tire? It sure as hell won't fit 'up front'.

I suppose you could put your overnighters up front and see if the wheel/tire will fit behind the seats, but you'd better bring something to wrap it up with, or you're going to have skid marks all over your interior.

 

Granted - a logistical puzzle. But consider also what you do if you are out with your wife 200 miles from a Porsche dealer or any service center that carries a new tire. Say it is dark and cold and perhaps raining as well. With no spare you are probably putting her up in the Bates motel (where you will have to return to retrieve her - in a day or so...whenever you finally get your tire - or perhaps in a rental ) while you ride in a flatbed to "where ever" or she rides in your lap in the flatbed for a few hours to "where ever". I experienced this alone and if I had a spare and my wife and had to either ditch her or the takeoff wheel, that wheel would be left somewhere for roadside assistance to retrieve or...wheel or divorce...wheel or divorce...the wheel's gotta go.

The common thought is: the spare comes out of the trunk, the luggage goes into the trunk, and the take off goes in the back where the luggage was...and perhaps you cut the tire along the sidewall as close to the bead as possible and toss it to reduce the size of the takeoff. Some say it cannot be cut - I think it can be as the sidewalls are glorified balloons.

Or, these cars are not viable for that sort of travel. At some point though, one must consider the way it actually plays out and plan for it...or live through it and find out the hard way. The main point is to have a realistic plan - it may or may not include a spare.

 

We had Dunlop run-flats on our '10 5 series BMW. I hated them.
Noisiest tires I have ever experienced!! Sounded like a bearing going out. The rears were bald in 17,000 miles of wife's driving. Worn evenly but bald. Fronts weren't even half worn. They were harsh too and couldn't seem to keep consistent pressure. TPMS was always going off and it is much more of a pain to reset than on the Pcar. I replaced them with Conti extreme contacts based on the high ratings from Tire Rack and couldn't be happier. The Contis are sooo smooth and quiet compared. I was beginning to dislike the Bimmer but the new tires have transformed it. I wouldn't even consider run flats on the Carerra until they become a LOT better.

 

Seems like RF is noisy, offers harsh ride, wears fast and expansive.

Any idea why RF wears faster?

 

I don't know - on my BMW 07 550i, they lasted all through my 3yr lease and had enough tread left that I didn't get dinged for it. I forget the mileage - maybe 20-25K. And they drove fine. I'd have never known if I didn't see the sidewalls - also had a donut in the trunk - double coverage, but that was '07 - don't think they do that any more unless the 7ers still have spares.

BMW still spec performance oriented tires for their cars so I never expected them to last very long. They surely lasted longer than Pilot Sports on the M cars I drove.

 

The sidewalls are extremely stiff (my Goodyear RF sidewalls were over an inch thick) which is what makes them "run flat". I would guess (I'm no engineer) that this allows less give in the carcass of the tire causing the tread to scrub more than a conventional performance tire and lessen the tire's ability to adapt to the contours of the road's surface. This is probably the culprit in the other problems that have been identified here.

I also noticed that the tread in my GY RF's actually got harder with age/mileage which I'm sure accelerated the wear.