Curbed rear tire, how bad is it?

[speedracerlo]

Slightly curbed one of my wheels for the first time... it sucks but I guess it was bound to happen. Damn construction in downtown LA...
I noticed there was a small tear around the tire where I curbed it. Can anyone tell me if this is ok to drive on?
These Michelin PSS are so damn soft...

[RichardP]

Probably depends what you hit to do that damage. It almost looks like you hit a nail or piece of metal, in which case that cut could be quite deep.

Can you tell how deep the cut is? If it's more than 1/4 inch or so, I'd replace the tyre.

[C5driver]

Sucks, dude...

Hate to be the wet blanket, but given the performance capabilities these cars I'd rather not risk a blown sidewall at speed.

Maybe get a couple local competent opinions (dealer, tire company, etc...). Of course, they just also happen to want to sell you a tire, but if you trust your SA or a tire shop, check with them.

[speedracerlo]

I hit a curb...
at least it'll only cost 50 to replace. I need to run over a nail..

[M6-Coupe]

Dude, if I were you, I would immediately replace the tire. These cars are crazy fast and you accelerate very quickly then you need to stop this 4400 lb car. Too much stress on tires. Just keep in mind, tires are the only connection between this heavy car and the ground. Not safe at all!

[chask]

Originally Posted by RichardP

Probably depends what you hit to do that damage. It almost looks like you hit a nail or piece of metal, in which case that cut could be quite deep.

Can you tell how deep the cut is? If it's more than 1/4 inch or so, I'd replace the tyre.

Originally Posted by C5driver

Sucks, dude...

Hate to be the wet blanket, but given the performance capabilities these cars I'd rather not risk a blown sidewall at speed.

Maybe get a couple local competent opinions (dealer, tire company, etc...). Of course, they just also happen to want to sell you a tire, but if you trust your SA or a tire shop, check with them.

Originally Posted by M6-Coupe

Dude, if I were you, I would immediately replace the tire. These cars are crazy fast and you accelerate very quickly then you need to stop this 4400 lb car. Too much stress on tires. Just keep in mind, tires are the only connection between this heavy car and the ground. Not safe at all!

A lot of it depends on the type of driving you do, and as RichardP mentioned, how deep it is. Did it get any of the belts, into them at all, or anything around them? Even nicking a belt just a little can ruin the strength. I would say if you drive like the proverbial little old lady who only uses it to go to church on Sundays and the store once a week, and never get over 25-30 mph you possibly could be just fine.

If you drive like a normal person I'd replace it as soon as you can. If you at all drive it the way it was designed to be driven, I'd get a new one on there as fast as I could and perhaps not do much driving until I had a new one broken in - and definitely no hard driving. Like the others above said, it's not worth the risk.

Even at legal speeds a belt separation could be very nasty. If you drive it hard or track it I would not even think about going again until I got that tire replaced. Heck, if it was me I'd be careful about just getting on the highway with it to commute. A lot of things can go on under that rubber coating on the sidewall, or the tread for that matter. I'd also watch for any bulge developing. That could be a bad sign about the belts.

Another way to look at this is to ask yourself what your life and current state of health worth to you? How much would you spend to prevent a permanent injury or death of you and/or someone you love? If this should fail you could be taking someone else with you too, or maybe you'd get them and come away from it without any problem(s). I know it's $400-500, but it's only $400-500 compared to you and yours.

Also, I am not sure I'd trust someone at a tire shop or my SA. They might be great tire people, the best on the planet, but how can they tell what is going on inside that cut in your sidewall? Can you? Frankly I don't see how anyone could know for sure without cutting it open (kind of like an autopsy) or at least peeing back the rubber and possibly cut the loose stuff off to look. I'm not sure it's worth it.

I'd definitely spend the money and get a new one. Yeah, you might be able to risk it and everything would work out fine, but why take the chance? As M6-Coupe said - your tires are the only connection between that 4,400 pound, almost 600 hp monster you are driving and the road. Without those tires in good working order all sorts of bad things can happen.

On a good note, judging by the picture of your tire I'm guessing your tires are fairly new - I can see three molding runners that look almost new in the pic. So you probably won't need to buy two tires. I would not replace just one side if there was much tread wear on the remaining tire. In that case I would get two new ones and keep the undamaged tire as a temporary spare for the next time something like this or worse happens.

Good luck with whatever you decide. I sure am sorry this happened to you.

[speedracerlo]

Appreciate all the advice. I will get this replaced asap. I only have about 3800 miles on the car and the left rear was replaced around 1500 miles ago. The damaged one is the right rear tire so I should be ok with replacing just one right?

[M6-Coupe]

Originally Posted by speedracerlo

Appreciate all the advice. I will get this replaced asap. I only have about 3800 miles on the car and the left rear was replaced around 1500 miles ago. The damaged one is the right rear tire so I should be ok with replacing just one right ?

If you have not driven the car very aggressively, then you have probably 90% thread left; So you should be fine to replace just the right one.

[chask]

Originally Posted by speedracerlo

Appreciate all the advice. I will get this replaced asap. I only have about 3800 miles on the car and the left rear was replaced around 1500 miles ago. The damaged one is the right rear tire so I should be ok with replacing just one right?

Originally Posted by M6-Coupe

If you have not driven the car very aggressively, then you have probably 90% thread left; So you should be fine to replace just the right one.

You can check the tread depth to be sure but I have a feeling M6-Coupe is probably right. Even with LSD I have a feeling that the right seems to take a bit more punishment. The left is most likely in better shape. Plus in my experience the Michelins tend to wear very well. Unless you've got an extremely heavy right appendage you're probably okay - 1500 miles is not much, especially considering that 200-300 of those should have been a more gentle break in.

Being an electrical type I am not sure I know how far off you can be without pushing things; I only know it's a bad deal to have a big difference. What constitutes a big difference is something I am not familiar with and I really don't want to guess.

There are also some places that will shave it for you. I think Tire Rack offers a service like that when you buy from them, but there are some local shops that will do that too.

I think the trouble with one new and one used tire that have different diameters is the LSD will think you are trying to turn a corner and be constantly working. Unlike a tire, these things are not cheap, and I would imagine especially not the variable one they use in the new cars. Plus I have read some somewhat conflicting things about the LSD used in the M cars. One on Wikipedia indicated that the LSD in BMW's (in general, not just the M's) used the brakes' anti-locking feature to slow the wheel going faster. As a result there is great break pad wear. Another link said the M cars had a more traditional version of the LSD, implying I thought that it was not brakes or not just the brakes, but did not elaborate more than that. With my nearly pathetic search skills I finally gave up trying to find out. Maybe someone else around here knows and could help. Anyway, I would not want my brakes running all the time. I am hoping it is at least some hybrid if not a traditional LSD.