JFTaylor

OK we don’t have a spare. Dealer told me that loss of air pressure means no more than 55 mph for 50 miles. After that, loss of the tire is expected. Which means that unless you’re in a war zone, you stop when you get a flat and call for help. So why the Run Flats? From what little I know:
1. Run Flats add $100 per tire. And more important:
2. Add weight. I’ve been told that “un-sprung weight” is bad – bad.
3. Make sense that a non-run flats have a more flexible sidewall – thus handle better.
So when it’s time to buy why not get regular tires and carry a can of Fix-a-Flat??
I'm posting on the C-5 board too.
Will use of Fix-a-Flat damage the pressure sensor inside the tire?

Scissors

Not that I've noticed. My non-runflats were about the same price as both previous sets of runflats I've had (Firestone and Goodyear.)

So do better brakes. It's a compromise. The weight and size of a spare in the trunk is also bad - bad.

Depends on the runflat. Michelin's PAX system of runflats doesn't require a stiffer sidewall. It does, however, require a special rim.

Because there are places in most cities that one travels through or near that you don't want to get stuck in. Same goes for certain kinds of weather. I don't want to be stranded in sub freezing temperatures.

Fix a flat, as I found out first hand, can be damn near useless.

Supposedly, yes. In my case it didn't, but it has damaged the sensors on others' cars.

DT

Howdy!

The "next gen" runflats seem to offer much better overall performance. I consider a runflat a "street" tire anyway, where the limits of a runflat are still way beyond what you should be doing on public roads.

To be honest, I really don't like driving a vehicle that doesn't have either 1) a conventional spare or b) runflats. You might notice from my sig I drive a Z06 which has neither. I plan on going to some Michelin runflats very soon (SRT Viper OEM's in fact). (I'll keep my CCW 18's as dedicated track wheels/tires)

I agree 101% with the "...you don't want to get stuck in..." comment, especially when we take the Vette on a road trip. I know there's always AAA, but I'd prefer not to me left waiting, especially if the wifey is with me, in a "bad situation". (There's always the combo of AAA+S&W but that's another whole can of worms )

I firmly believe the slight performance penalty is offset by all the safety benefits. FWIW, I've read a number of stories of people driving much farther than 50 miles on an EM type tire, YMMV of course.

Pio

The C5 Z06 and previous generation BMW M5 had standard tires with what was basically a "fix-a-flat" bottle and a cigarette lighter operated mini-air pump.

I want to replace my tires with Nittos or GY Super Car tires.

JFTaylor

DT, I do "the combo of AAA+S&W"

HalM

JFT...great post...

Here's my theory. It starts with the notion that in the world of Physics/Engineering there is no magic just real world tradeoffs.

No one liked the super stiff sidewalls of the early runflats.
Now we have these newer runflats that will not go as far but have a more compliant sidewall.

Guess what, if I soften the sidewall and make it more like a regular tire...guess what I get?? ---a regular tire! They haven't gone quite that far but you get the idea...

Pio

ivan111

Will the C6 Z06 have run-flats also?

Vette_DD

Actually, on the C6, the owner's manual and the "Getting to Know Your Corvette" manual say that the tire can operate effectively with no air pressure for up to 100 miles at speeds up to 55 MPH. It also says that if you drive on a deflated EMT for 25 miles or less and at speeds of 55 MPH or less, there is a good chance the tire can be repaired.

Scissors

Yes.

ivan111

So that means that there is going to be a grip or handling compromise in the new Z.....

If the new Z06 wants to outhandle its main competitors it has to use regular tires.......

I can accept GM using Run-flats in the base C6 but in the Z06 no......

Scissors

Any car that doesn't come with drag radials has a grip or handling compromise.

As long as it kicks the crap out of the competition, I don't care. Besides, with the short sidewalls such large wheel diameters bring, a runflat's stiffer sidewall has a minimal effect on handling and grip. Compound and tread pattern matters far more.

ivan111

I read that the C6 Z06 sidewalls are going to be lower profile that the base C6?

Base C6 is 40 at front and 35 at the rear

C6 Z06 is 35 at front and 30 at the rear...

Is that correct?

Scissors

C6 Z06 rear tires:

ivan111

Rears are 325 not 345 like i have been hearing.....

Somebody also said that the Z06 tires speed rating is Y that is up to 186 mph so the Z06 top speed should be identical to the base C6?

Scissors

It's possible that these are an optional tire for the Z06.

But all of the good intel I've heard is that they're 325s. I don't know where this 345 stuff came from.

ivan111

What about the tires speed rating?

Scissors

I have no idea.

But Y rated tires are good only up to 186. Z rated is good for 155+ (leaves a lot of leeway.)

ivan111

From the C6 Z06 and C6R pic you can see the tire Y speed rating, if that is true or not will have to wait until january......

Scissors

Interesting.

Yeah...could be an option.

Edit: The close up of the yellow car's wheel and tire shows P275/35ZR18 on the front.