: No Runflat = not so good



wildwhl
09-13-05, 10:39 PM
V-freaks.

Last week it happened - blow out of 275/40 GSD3 on the rear when going about 60 mph downhill off-camber long right hand sweeper (driver's tire failed). There was a large screw or nail in it apparently.

At any rate - I'm back on the fence about running without run-flats. I have no spare - only the goo and compressor and they were useless in this case. The part that concerns me is that I had my one year old son in the car with me, and it was a pretty hairy ride to get out of the way of traffic to say the least. Good thing I had let the red Z3 fly past without a chase - or I would have been going somewhat faster :suspense:

So, my 4 widened rear wheels are now only 3...and I'm just venting and reminding people that flats do occur. I've had two blowouts, same wheel position, in the life of the V - one about a year ago. They're not as rare as most of us would hope. I did have some warning but didn't pay attention to it - the TPS was indicating 26 psi when I got in the car in the morning a few minutes prior - but it was colder than it had been and I didn't pay proper attention.

lasstss - any more progress on the spare wheel adapter (and sorry if I've missed it in my absence)?

heavymetals
09-13-05, 10:49 PM
Good you aren't racing around with your kid in the car.

:hide:

wildwhl
09-13-05, 10:54 PM
heavy -

must teach them young or they'll never fully appreciate it :D

Nope, I'm totally sane with my family or any other passengers in the car (save for a few speed freaks I know). Was going 60 in a 55 - or just pacing traffic officer!

Dave's V
09-13-05, 11:04 PM
Same position on the same car? There might be a problem with the car. Two blowouts in a life time is rare, same car extremely rare, same wheel? go buy a lottery ticket.

Dreamin
09-13-05, 11:11 PM
Potenza RE050A's come in 245/45 and 275/40 in runflats... should outhandle D3's, but they wont last as long, and they ain't cheap.

wildwhl
09-13-05, 11:30 PM
Dave's V -

I have that kind of luck, trust me :)

Dreamin - those are now on my short list, thanks.

AmesCTS-V
09-14-05, 01:11 AM
I've never in my life had a flat or blow out. If I did I've got OnStar and my cell phone so I'm not too worried. But it is a good heads up for those that don't like the OnStar and cell phone options.

Dreamin
09-14-05, 01:32 AM
No flame intended... but exactly how is onstar and a cell phone going to prevent you from getting a front blow-out at 70+ mph... losing control of the car... smacking the concrete barrier or hitting other cars or rolling over...

I think that was Bill's main point... this wont happen with RF's.

wildwhl
09-14-05, 01:42 AM
Dreamin :thumbsup:

urbanski
09-14-05, 08:10 AM
buy a spare stocker and throw it in the rear tub....of course it won't prevent your blowout, but you'll be able to get back on the road

tedcmiller
09-14-05, 09:26 AM
Run-flat tires are the way of the future. Eventually, all cars will have run-flats and non-run-flats will be virtually non-existent. In fact, I would not be surprised if within the next 10 years the NTSB mandated run-flats for all cars.

rand49er
09-14-05, 09:47 AM
This has probably been posted to death elsewhere already, but is there a good, reasonably-priced, all-season run-flat out there? :confused: (That's probably too many constraints for the world of tires. :yup: )

CTS-VETTE 550HP
09-14-05, 10:33 AM
No flame intended... but exactly how is onstar and a cell phone going to prevent you from getting a front blow-out at 70+ mph... losing control of the car... smacking the concrete barrier or hitting other cars or rolling over...

I think that was Bill's main point... this wont happen with RF's.

you read my mind i have been in a situation like this but luckly i had run flats.

a64pilot
09-14-05, 10:49 AM
Run-flat tires are the way of the future. Eventually, all cars will have run-flats and non-run-flats will be virtually non-existent. In fact, I would not be surprised if within the next 10 years the NTSB mandated run-flats for all cars.
Way back when Lee Iaccoca took over Chrysler one of the things he was trying to do away with was the spare tire. If in the initial design of the automobile the spare and associated equipment was eliminated the snowball effect of losing that weight and space the car ended up weighing something like 400 lbs. less and got something like 2 mpg better while still meeting all of the safety and space etc. goals.
Apparently if you lose around 40 lbs or so in the design phase then you need slightly less engine that requires a smaller tranny and now the car is lighter so the suspension is lighter so the brakes are smaller etc. etc.
It's nice to have a car with crumple zones, air bags, shoulder harnesses etc., but not enough attention is given to an automobile that can avoid the wreck to begin with.
When people start talking about how safe they feel in their SUV I point out that that wreck they had and walked away from I wouldn't even have had as my vehicle stops in a much shorter distance. They get a confused look on their face as this is obviously beyond their comprehension.
Bottom line, this car as supplied from the General has several passive safety features that should be looked at pretty hard before discarding. I.E. run flat tires and turning off stabilitrack because you like to be the one in charge or whatever. I'm glad it came with run flat tires. Without them I would have a heavier car that had less performance and I'm sure wouldn't have a way of monitoring tire pressure while driving. I don't even mind the short life of the tire. Good sticky tires don't last long and I'm sure if the car came with a longer lasting tire it would also have come with a suspension that matched it. O.K. I'm sorry I'm off my soap box now.

AmesCTS-V
09-14-05, 01:41 PM
No flame intended... but exactly how is onstar and a cell phone going to prevent you from getting a front blow-out at 70+ mph... losing control of the car... smacking the concrete barrier or hitting other cars or rolling over...

I think that was Bill's main point... this wont happen with RF's.
Anything can happen, that RF can rip apart and do worse damage than just a flat, much less likely, but possible.

Blowouts do happen and you don't just immediately crash and burn because of them. Yeah it's a possibility, but it's much much much more likely you crash or get hit for some other reason.

With low profile tires and firm sidewalls they will handle a blowout better than regular tires. OnStar and a cell phone will handle getting someone out to fix the flat.

If wildwhl has had 2 blow outs on the same location/rim on this car already he has other problems to figure out. Or he is driving at 70mph through the HomeDepot lot too often.

RobzBLKV
09-14-05, 01:47 PM
Bah. I haven't hada blowout in a car in probably 20 years and I didn't suffer anything other than a flat tire when I did have one. I am not buying those heavy, expensive, short life tires again. A spare has been fine for what, 80 years? Nothing in the past decade happened that made the spare suddenly not fine. Run flats are an option that probably will be mandated sometime in the future, but the run flat craze started, imo, b/c people that weren't properly trained to drive big, heavy, top heavy vehicles over-corrected when a faulty tire blew and rolled their already roll happy suvs.

Bill, I would say that your example indicates that a competent driver will be able to control the car in the event of a tire failure, not an indication that we should all run for the nearest run flat tire seller. I am fairly certain, and hope very much, that everyone that buys a V has the driving skill necessary to control the car in the event of a blow out.

A64pilot, if you take your concept to its logical end, you wind up with electronically driven cars that don't have any human input and therefore don't have any risk of human error. Might make the roads "safer," but I am not interested. I don't want the car driving for me. That means I will turn off the electro nannies when I am trying to determine my skill level or improve it b/c I want to learn how to drive the car, not how to make the electro nannies drive it for me. As for the tires, when there are credible studies that indicate your family is at siginificantly less risk of injury b/c of them, I will consider the issue again. Until then, I think it's a belt and suspenders type of safety feature.

Yes, I hope very much that I don't eat these words when I replace my tires with normal tires.

WillyV
09-14-05, 02:32 PM
The title of this thread should be changed to "No Runflat and No Spare = Not Good".

I don't understand why those who've switched to non RFs don't buy and extra wheel, mount a tire, and throw it in the well in the trunk with a jack and lug wrench. I did just that after switching to GSD3's and couldn't be happier with the decision. I've got a much better ride on the highway and around town (with minimal loss in handling) and the peace of mind of having a full spare.

AmesCTS-V
09-14-05, 02:39 PM
The title of this thread should be changed to "No Runflat and No Spare = Not Good".

I don't understand why those who've switched to non RFs don't buy and extra wheel, mount a tire, and throw it in the well in the trunk with a jack and lug wrench. I did just that after switching to GSD3's and couldn't be happier with the decision. I've got a much better ride on the highway and around town (with minimal loss in handling) and the peace of mind of having a full spare.
Because it adds weight and takes up space. Blow out's are rare so I'm fine counting on OnStar. In all likelyhood I'd be close enough to home I'd just call a friend to run something out to me.

pmsteinm
09-14-05, 05:01 PM
Two blowouts in the same spot? Are you sure your aren't living in Indy and using Michelin tires?

timmayz
09-14-05, 08:44 PM
If runcraps handled better than regular high performance tires, wouldn't they use them for racing? Z06's don't come with them, maybe weight was the factor there... :hmm:

Rich H
09-14-05, 08:58 PM
Two blowouts in the same spot? Are you sure your aren't living in Indy and using Michelin tires?

It happens - believe me. I have had only 2 blowouts while driving in my life and both happened on the same stretch of road within ~1/4 mile of each other - in different vehicles and more than 10 years apart. Both as a result of damn debris on the road.

The first time I had plain Goodyear Eagle GT4s and had to pull over and install the spare. The second time, in my V, I just kept driving with the run-flats- I couldn't have stopped if I wanted to because of construction barriers on the road apron. I drove the car home that night and got it replaced at my convienence a few days later

What are the chances of this happening - who cares? It happened - and the second time was a lot less hassle. I'm a believer now that run-flats are worth the extra cost and inherent disadvantages. However, they will get better, and cheaper, in the future.

Dreamin
09-14-05, 10:28 PM
If runcraps handled better than regular high performance tires, wouldn't they use them for racing? Z06's don't come with them, maybe weight was the factor there... :hmm:

The current generation RF's are pretty amazing... the stock RF's weigh 1 lbs more than Potenza S03's and 2 lbs more than the GS-D3. And they will out handle all but a few non-RF's.

And the C6 Z06 has EMT's... the *exact* same compound as the V (Eagle F1 Supercar EMT) :thumbsup:
Good for 11.50 @ 127.10 and 7:43 at the ring!

ntechnic
09-15-05, 02:27 AM
Two blowouts in the same spot? Are you sure your aren't living in Indy and using Michelin tires? :highfive:

As to racing, there are several reasons, #1 being weight. Tires are unsprung weight, unsprung weight is the arch nemesis of all racers that turn corners. Run flats are heavier. What's good for racing is often not good for the street and vice versa. It's the overall package, the balance that's key to a good street or race car.

In September, 1999, I was on the freeway on a typical roasting hot SoCal Sept. afternoon, in our new Explorer, with my 8-month pregnant wife. The truck suffered the dreaded Firestone rear tire blow out. Let me note here that I grew up circle track racing, on dirt and asphalt, started driving dirt farm roads at 12 in 3-speed pickup trucks--I'm as comfortable sideways as straight away. I understand why all those trucks rolled, in all my years of racing, I never had a vehicle snap that fast. The truck snapped so sideways in a blink of an eye that we rolled up on two wheels. My wife says she remembers looking out her passenger window and seeing nothing but freeway concrete.

Truck didn't roll, it was a fast snap, but I caught it, put it back on four wheels, and eased to the shoulder. The guy behind us stopped too to see if we were OK. He said it looked like a TV stunt--he couldn't believe we didn't go over, much less recovered and stayed in our lane. Chaulk it up to luck a decade of roundy pounding.

A few hours later my wife went into premature labor, our son was born, and was in neo-natal intensive care for two weeks. He turned out great. Was there a connection? Who knows, but there could have been.

When reminded of this, and with two children in the car a lot of the time, I've decided I'll stick with the run flats. Hey, what the heck, I'm a dad, I like air bags, seat belts, etc., I'll just add run flats to my list of things I like.

lal373
09-15-05, 01:18 PM
I agree with WillyV.

Disadvantages of spare are:
(1) Cost -- but even after paying the exhorbitant ransom for a new rim from GMdirect, I came out ahead on the first set of new tires because GSD3 is so much cheaper than RFs.
(2) Space and weight -- but still have full CTS trunk even without the hidden area (after removing liner), and the weight increase is trivial on this car, with no impact on performance.

Advantage of having spare is obvious when you have full failure on the road, but another advantage became clear to me when I got slow leak in RF: I couldn't just switch on the spare and get the tire fixed or replaced at my convenience --the V would be out of commission until I could get replacement shipped from TireRack and then find time to go sit at the dealer or Goodyear while they scratched up my rims. Since I didn't have the luxury of that available time, and didn't want to drive on the low-pressure tire, I carried around a pump in the trunk and refilled it each time it sat for a few hours.

My personal view as a consumer, not a car expert: runflats are great technology not yet ready for prime time. Until price comes down and they figure out how to reliably replace them without scratching rims (or charging ridiculous fees for the extra care required, such as the $80/wheel my dealer requested), a good non-RF like the GSD3 is better bet .... and the disadvantages of spare are outweighed by the advantages.

6104696
09-15-05, 01:26 PM
I am watching with interest to see how the Honday Odyssey will fare (market-wise) with the Michelin PAX runflats. If that is a successful program, then that will really signal the arrival of the runflat to the mainstream.....

then let the patent lawyers have their field day......

Dreamin
09-15-05, 03:24 PM
610: How is PAX superior to current runflats? It's still a special tire, still only goes 125 miles, and needs a special wheel?!

RobzBLKV
09-15-05, 05:11 PM
Dreamin, you didn't go far enough. B/c it needs a special wheel for tire mounting and dismounting, it needs special equipment. The equipment is not readily available and at best, you are stuck going to the dealer. When the cars first came out, the dealers didn't have the equipment either and their solution was to sell you a new wheel with a new tire already mounted to it. I assume at least the dealers can handle the wheels now, but I haven't really asked . . . .

Rich H
09-15-05, 11:05 PM
:highfive:

In September, 1999, I was on the freeway on a typical roasting hot SoCal Sept. afternoon, in our new Explorer, with my 8-month pregnant wife. The truck suffered the dreaded Firestone rear tire blow out. Let me note here that I grew up circle track racing, on dirt and asphalt, started driving dirt farm roads at 12 in 3-speed pickup trucks--I'm as comfortable sideways as straight away. I understand why all those trucks rolled, in all my years of racing, I never had a vehicle snap that fast. The truck snapped so sideways in a blink of an eye that we rolled up on two wheels. My wife says she remembers looking out her passenger window and seeing nothing but freeway concrete.

Truck didn't roll, it was a fast snap, but I caught it, put it back on four wheels, and eased to the shoulder. The guy behind us stopped too to see if we were OK. He said it looked like a TV stunt--he couldn't believe we didn't go over, much less recovered and stayed in our lane. Chaulk it up to luck a decade of roundy pounding.

Part of the technology that runflats must include are the tire pressure monitors - by law. Tire pressure is probably the single biggest factor, outside of road hazards, that will influence the longevity and safety of a tire. In the case of the Firestone tire that failed on your Explorer I assume it was likely caused by overheating due to underinflation combined with weaknesses in tire construction.

The use of runflats forces the driver to monitor his tire pressure much more closely than would be done with regular tires. This fact alone, could probably save more than a few lives on the open road. If tire pressure monitoring is imposed by legislation in the future on all vehicles, regardless of tire construction, we can at least thank the runflat for getting the momentum started.

Dave's V
09-15-05, 11:25 PM
People keep mentioning the weight you save when you are using runflats, but I read somewhere on this forum that the tub weighs around 40 lbs because of a support bar. Add 2 lbs heavier per tire with a run flat and the car may gain around 10 lbs. Most of us can save more weight by going on a diet and exercising more. The Pontiac Grand Prix GXP uses a can of fix a flat as a spare. That saves the most weight.

Run flats have an excellent safety advantage but like someone mentioned, a TPS can catch most blowouts. A high speed rated regular tire is extremely safe at 1/2 the cost, twice the life, a lot smoother and quieter.

Run flats do go bad and it is a lot harder to replace a run flat than a regular tire.

I also agree that cars should be designed to avoid accidents first, then protect in an accident second. The only problem is that most people have a better chance of getting hit by someone else, then causing their own accident.

6104696
09-16-05, 09:48 AM
610: How is PAX superior to current runflats? It's still a special tire, still only goes 125 miles, and needs a special wheel?!

I never said it is superior, but the application on the Odyssey is a hell of a lot more mainstream than our F1's....could be the old VHS/Betamax story all over again. The inferior product won the market because of volume and availability.

(OK, "allegedly" inferior product; I do not want to restart a 25 year old debate)

dhg

DoctorV8
09-16-05, 11:23 AM
If runcraps handled better than regular high performance tires, wouldn't they use them for racing? Z06's don't come with them, maybe weight was the factor there... :hmm:

The new C6 Z06 does have runflats, as does the Viper.