Run Flat limits

[ard]

Originally Posted by Tomaz

Thanks. Thats exactly what I wanted to hear.

Im sure it was.

25 miles at 75mph?? IMO...that is a tire that was almost surely over heated.

One of the reasons mfgs tend to recommend replacement is most rire shops cannot/do not understand tire damage. It is hard to ascertain when the carcass has been damaged due to overheating.... safer to say 'we wont repair a runflat that has been driven on'

why would you drive on a runflat and ruin the tire, when a spare and a tire repair can save the tire?

[Tomaz]

Originally Posted by ard

Im sure it was.

25 miles at 75mph?? IMO...that is a tire that was almost surely over heated.

One of the reasons mfgs tend to recommend replacement is most rire shops cannot/do not understand tire damage. It is hard to ascertain when the carcass has been damaged due to overheating.... safer to say 'we wont repair a runflat that has been driven on'

why would you drive on a runflat and ruin the tire, when a spare and a tire repair can save the tire?

Ruining a tire is a small price to pay for returning home or a safe harbor safely. Being on the side of the road changing a tire exposing me and my vehicles occupants to danger is not a vision i embrace. I am glad to be running on run flats that can deliver me to safety without having to pull off the side of the road. BMW is known for great engineering and leading edge vehicles. BMW's endorsement of run flats is good enough for me.

[trucky]

Originally Posted by ard

Im sure it was.

25 miles at 75mph?? IMO...that is a tire that was almost surely over heated.

One of the reasons mfgs tend to recommend replacement is most rire shops cannot/do not understand tire damage. It is hard to ascertain when the carcass has been damaged due to overheating.... safer to say 'we wont repair a runflat that has been driven on'

why would you drive on a runflat and ruin the tire, when a spare and a tire repair can save the tire?

Funny you should mention overheating as that was my first concern. Being an old truck driver with over a million miles crossing Donner Pass most days I take my tires and safety very seriously. One of my OCD habits during and after any trip is to actually feel the tires with the back of my hand and "taste" the temperature. While not an entirely scientific process it does allow me to know if one tire is significantly hotter than another. Running duals on truck and trailers it's not always visually apparent that one of your tires is low. The hand trick has saved me from adding to the tire carcasses along the road by discovering a hot tire and taking appropriate action.

I did the same with my X5 after arriving and found no discernible difference between the low RFT and the other 3 tires. I guess the proof will be to see if it survives as long as the other tires over time.

And why run on a RFT? Isn't that exactly the point of having RFTs? Having 3rd row seating there is no place to stow a spare. I was originally thinking about replacing the RFTs with non RFTs when they wore out but now I'm rethinking those thoughts.

Not trying to be adversarial at all Ard. I highly value your opinions on this and other BMW forums. Just sharing my personal perspective.

[ard]

Originally Posted by trucky

Funny you should mention overheating as that was my first concern. Being an old truck driver with over a million miles crossing Donner Pass most days I take my tires and safety very seriously. One of my OCD habits during and after any trip is to actually feel the tires with the back of my hand and "taste" the temperature. While not an entirely scientific process it does allow me to know if one tire is significantly hotter than another. Running duals on truck and trailers it's not always visually apparent that one of your tires is low. The hand trick has saved me from adding to the tire carcasses along the road by discovering a hot tire and taking appropriate action.

I did the same with my X5 after arriving and found no discernible difference between the low RFT and the other 3 tires. I guess the proof will be to see if it survives as long as the other tires over time.

And why run on a RFT? Isn't that exactly the point of having RFTs? Having 3rd row seating there is no place to stow a spare. I was originally thinking about replacing the RFTs with non RFTs when they wore out but now I'm rethinking those thoughts.

Not trying to be adversarial at all Ard. I highly value your opinions on this and other BMW forums. Just sharing my personal perspective.

Good input.

While the point of having a RFT is to be able to drive on them, the question of "once driven on will this retain a safety rating" drives repair shops (and BMW) to declare 'no'. This protects them against the idiot that damages a tire, goes to a shop and an untrained tech pops a plug in a tire with a damaged carcass.


Personally havent seen enough internally damaged tires to know when they are toast- once I saw a tire with fine rubber 'shreads' coming off the interior. But in terms of looking at a puncture, feeling for delams, how to inspect the inner surface of the tire- I dunno.

I carry a spare, Id pull off the next exit or safe spot. My wife would do the same and call AAA. And Id have no qualms about repair of the tire in that scenario.

Finally I applaud the 'we will see how it fares' attitude. I cannot tell you how annoying the 'gotta pay to play' and 'are you willing to risk your FAMILY to save a few bucks" responses are.

PS Put that tire on the rear, just in case....

[Quicksilver]

Echoing MD's comment,

PS: My non tech opin is to not drive an AWD X on a de aired RFT for very far or very fast...

[Tomaz]

As an aside. Last year I brought my 2001 X5 with 19" Bridgestone's into my Goodyear tire shop because I had a nail in the rear tire and a slow leak. After a quick inspection they informed me that they couldn't repair the tire because it was ""too worn". I looked at the tire and the wear bars were not even close to showing. They said that on the inside of the tire it was worn so there was no tread left. I said that X5's always wear that way. They refused to repair the tire. I had used that shop for 10 years for all of me families cars. I found another shop that did repair the tire and that are my new go to tire shop. Is this another government rule to keep us safe from ourselves?

[ard]

Originally Posted by Tomaz

. I said that X5's always wear that way.

. Is this another government rule to keep us safe from ourselves?

BMWs wear tires like that because BMW dealers put too much toe on them. Owners are clueless, thinking 'oh its for handling' or 'its the camber' or 'all BMWs do it'

I have no issues with tire shops not repairing tires that are abnormally worn- not a government thing

[Tomaz]

Originally Posted by ard

BMWs wear tires like that because BMW dealers put too much toe on them. Owners are clueless, thinking 'oh its for handling' or 'its the camber' or 'all BMWs do it'

I have no issues with tire shops not repairing tires that are abnormally worn- not a government thing

I believe the rear tires on X5's wear the inner edges because of too much negative camber. This is designed in at the factory for better handling limits. I had my tuner dial out as much negative camber as possible and I was still at 1.5 degree negative.

[ard]

Originally Posted by Tomaz

Ruining a tire is a small price to pay for returning home or a safe harbor safely. Being on the side of the road changing a tire exposing me and my vehicles occupants to danger is not a vision i embrace. I am glad to be running on run flats that can deliver me to safety without having to pull off the side of the road. BMW is known for great engineering and leading edge vehicles. BMW's endorsement of run flats is good enough for me.

Whatever dude. Someone is drinking the BMW koolaid...

"small price to pay"? Why not pay body guards to follow you and your family around from safe harbor to safe harbor? Out in the wilds of Los Gatos....

Originally Posted by Tomaz

I believe the rear tires on X5's wear the inner edges because of too much negative camber. This is designed in at the factory for better handling limits. I had my tuner dial out as much negative camber as possible and I was still at 1.5 degree negative.

I will usually engage with folks and let them know where they might be mistaken. I know a bit about alignments.

But you seem so wrong, and comfortably smug about it.

Enjoy

[Tomaz]

Originally Posted by ard

Whatever dude. Someone is drinking the BMW koolaid...

"small price to pay"? Why not pay body guards to follow you and your family around from safe harbor to safe harbor? Out in the wilds of Los Gatos....


I will usually engage with folks and let them know where they might be mistaken. I know a bit about alignments.

But you seem so wrong, and comfortably smug about it.

Enjoy

I was trying to have an intelligent conversation about run flats. I welcome your comments if you can tell me "a bit about alignments". If you want to insult me and other "clueless" X5 owners about where I live or being smug I am glad to continue this off line...