Tires designed for negative camber

[y_p_w]

I've been getting decent wear out of a set of Continental Extreme Contact DWS. However, I'm still getting extreme wear on the inside edge - probably as a result of the negative camber in the back and that I don't corner the heck out of it.

I'm wondering if there might be a tire to counter those effects, or if adding rubber to the inside edge would probably negate the handling benefits.

 

[turtlevette]

I've never heard of such. But you might be on to something.

 

[expat]

What vehicle?

How much camber is there?

Can it be adjusted?

I have a similar problem with my Triumph Spitfire. The rear suspension is set to give 2 degs neg camber, but that can be a lot more if I have a full load.
I have solved the problem by fitting Air adjustable ride height shocks on the back.
Adding a few lbs when I have a load, or intend to take a road trip helps even out the tire wear.

 

[FetchFar]

Originally Posted By: y_p_w
I've been getting decent wear out of a set of Continental Extreme Contact DWS. However, I'm still getting extreme wear on the inside edge - probably as a result of the negative camber in the back and that I don't corner the heck out of it.

I'm wondering if there might be a tire to counter those effects, or if adding rubber to the inside edge would probably negate the handling benefits.


Yes, a tire made for a negative camber is the BMW-approved tires. Tirerack.com customer service can point you toward them. They have a 5-pointed star symbol on the tires, and are available in several sizes and brands.

 

[FetchFar]

the aforementioned BMW star-spec tires actually have tread on the inside to compensate for the negative camber properly (wear).

 

[CapriRacer]

Originally Posted By: FetchFar
the aforementioned BMW star-spec tires actually have tread on the inside to compensate for the negative camber properly (wear).


I don't think so.

It's true that BMW's spec lots of camber - and it's true that tires approved by BMW have stars on them, but I don't think they have - oh, let's call it asymmetrical tread depths.

My understanding of why high cambers are used is to allow the tire to have a good footprint when it is cornering. It compensates for both the roll of the vehicle and the deflection of the tire.

So if anything is done to get a good wear footprint - either by using little camber or building a tire with a reverse camber - then when the car is cornering, the camber won't be optimal for cornering.

So not only do I think this isn't true (and I think I would know if BMW tires had this feature), but I don't think it makes sense to specifically build a tire that way.

And to answer the OP's question: I don't think there are tires designed to do that - BUT - there are tires that are less wear sensitive to camber than others - and I'll bet that is what Tire Rack is pointing people to.

 

[Mud]

Originally Posted By: expat
What vehicle?

How much camber is there?

Can it be adjusted?



+1 some info here would be nice.

I had an issue with rear tires wearing out on the accord. Rather than go with higher cost tires all the time, I installed adjustable rear control arms for very reasonable cost (stock arms were not adjustable). Brought the camber in without any driveability issues - the current set of Yokohamas on the car look very good at a bit over 40K miles. I'm amazed at the amount of vehicles going down the road looking like a pyramid from the back from excessive neg camber.

 

[zzyzzx]

One can normally adjust camber by installing a kit.

 

[IndyIan]

You could go to a higher profile tire, with smaller rims. I've found that they don't wear as unevenly with my DIY autocross alignments.
Also if camber isn't adjustable, maybe the toe is? Removing some toe in or going to zero toe in might help

 

[FetchFar]

Originally Posted By: CapriRacer
Originally Posted By: FetchFar
the aforementioned BMW star-spec tires actually have tread on the inside to compensate for the negative camber properly (wear).


I don't think so.

It's true that BMW's spec lots of camber - and it's true that tires approved by BMW have stars on them, but I don't think they have - oh, let's call it asymmetrical tread depths.

My understanding of why high cambers are used is to allow the tire to have a good footprint when it is cornering. It compensates for both the roll of the vehicle and the deflection of the tire.

So if anything is done to get a good wear footprint - either by using little camber or building a tire with a reverse camber - then when the car is cornering, the camber won't be optimal for cornering.

So not only do I think this isn't true (and I think I would know if BMW tires had this feature), but I don't think it makes sense to specifically build a tire that way.

And to answer the OP's question: I don't think there are tires designed to do that - BUT - there are tires that are less wear sensitive to camber than others - and I'll bet that is what Tire Rack is pointing people to.


They make star-spec tires have harder/more-surface-rubber and assymetrical stiffness to compensate for uneven tire wear resulting from negative camber. (You were thinking they were lopsided, thicker on one side, not the case.)

 

[dparm]

Camber doesn't really eat tires unless you have something crazy like -2 degrees or more. Toe is what absolutely destroys tires.

OP, why does your car have enough negative camber to cause these problems? My M3, which is a pretty aggressive car, doesn't have this issue nor have either of my two Audi S4s (also sporty cars).

 

[OVERKILL]

Originally Posted By: dparm
Camber doesn't really eat tires unless you have something crazy like -2 degrees or more. Toe is what absolutely destroys tires.

OP, why does your car have enough negative camber to cause these problems? My M3, which is a pretty aggressive car, doesn't have this issue nor have either of my two Audi S4s (also sporty cars).


Nor does my M5. And this is the first I've heard of a "star spec" tire, my PSS's I don't believe are, and they wear perfectly flat.

EDIT: Just looked it up:

Originally Posted By: BMW

NOT JUST ORDINARY TIRES.
BMW Star Approved Tires.
To maintain the highest level of quality, BMW Approved Tires are given a star approval rating (★). The star symbol indicates that the tires have been optimally tuned for each BMW model. In cooperation with the tire manufacturer, each tire is designed and tested to meet BMW’s uncompromising standards of dynamism, ride comfort, and safety. In comparison, a replacement tire that is not BMW star approved is designed for a wide range of models and various vehicle manufacturers. Tires that are BMW star approved virtually have all components developed to BMW specifications.


http://www.bmw.ca/ca/en/owners/accessories/tires/star_approved_tires/Star_Approved_Tires.html

Watched the little video on there and they made no mention of the tires being "specifically because BMW's have negative camber" either. It was all about tighter standards for tire construction as compared to a "generic" tire

 

[Quattro Pete]

Originally Posted By: dparm
Camber doesn't really eat tires unless you have something crazy like -2 degrees or more.

The standard factory recommended rear camber on my 530i is -2.17 degrees. However, that's just the mid point. BMW allows a range of camber values from -1.75 to -2.59. If I set it to -1.8, I find the rear tires wear just fine.

 

[FetchFar]

I don't run BMW-specific star spec tires on my 07 530ix and have no problems. However, if you are really driving hard, the rear camber starts to affect wear on one side of the tire. Yes, the star spec tires do compensate for this to some degree, their main performance claim really. BMW directly told (trained) a trusted friend/neighbor of mine who is a service advisor at a dealership about how BMW works with the tire makers and gets some assymetry to handle camber.

 

[Quattro Pete]

Originally Posted By: FetchFar
BMW directly told (trained) a trusted friend/neighbor of mine who is a service advisor at a dealership about how BMW works with the tire makers and gets some assymetry to handle camber.

So does that mean they make specialized front and rear tires since it's only the rear that has significant negative camber???

 

[rslifkin]

If you corner gently, you might need to run less camber than spec-ed. Also, if you're getting notable camber wear in the rear, have the toe adjusted closer to zero, as toe amplifies camber wear a lot.

 

[OVERKILL]

Originally Posted By: FetchFar
I don't run BMW-specific star spec tires on my 07 530ix and have no problems. However, if you are really driving hard, the rear camber starts to affect wear on one side of the tire.


Both the driving habits of dparm and myself I am quite certain meet your definition of "driving hard". Yet as I said, my car wears the tires flat across. And I of course, due to having a factory staggered setup, cannot rotate.

Quote:
Yes, the star spec tires do compensate for this to some degree, their main performance claim really.


If this is the case, why is there no mention of it on their website nor in the video that specifically speaks as to the benefits of the star designation? If it was the main claim to fame, why do they advertise everything else but that?

Quote:
BMW directly told (trained) a trusted friend/neighbor of mine who is a service advisor at a dealership about how BMW works with the tire makers and gets some assymetry to handle camber.


Quite odd then given that CapriRacer, who works for a tire manufacturer, hasn't heard of this part of it then eh?

 

[exranger06]

If the tires are asymmetrical, they would have to indicate on the tire somewhere which side has more tread depth. If the car has negative camber, you would need to make sure the side with the most tread depth is on the inside. If you installed them with the deeper end on the outside, it would make the wear problem even worse! And you wouldn't be able to rotate the tires without dismounting and remounting them to the rims. And if they're directional tires, it would be impossible to rotate them at all.

 

[FetchFar]

Originally Posted By: Quattro Pete
Originally Posted By: FetchFar
BMW directly told (trained) a trusted friend/neighbor of mine who is a service advisor at a dealership about how BMW works with the tire makers and gets some assymetry to handle camber.

So does that mean they make specialized front and rear tires since it's only the rear that has significant negative camber???


Great question. Wonder if most BMW service reps would know. Hard to find out info about star spec BMW variations of tires.

 

[FetchFar]

Originally Posted By: exranger06
If the tires are asymmetrical, they would have to indicate on the tire somewhere which side has more tread depth. If the car has negative camber, you would need to make sure the side with the most tread depth is on the inside. If you installed them with the deeper end on the outside, it would make the wear problem even worse! And you wouldn't be able to rotate the tires without dismounting and remounting them to the rims. And if they're directional tires, it would be impossible to rotate them at all.


I was told they reduce wear rates on the inside edge with harder compounding on that side, not thickness, to get even wear. Supposedly this all comes straight from BMW training! I'd like more confirmation too.