[MarkRacerX]

I just took my car in, as my rear tire totally fell apart. They weren't bald but about at wear bar. The inner tread bar totally peeled off!! Hear I was thinking a defective tire as I have never see a tire peel like this and still had tread. Bmw tech stated due to the stock rear camber, insides wear much more and not uncommon for them to wear like that. He stated they can set less rear camber " Out of Spec " to get more tire wear +5k-+10mi out of the tires and better winter traction. I have an Xi so w/ the awd not too worried about traction, but has anyone had this done to get increased tire life? It makes sense less camber angle = less wear / longer life, just curious it I will even notice fr handling perspective?

Thanks!

Mark

Luckily the timing as I just ordered new wheels/tires, whew! Those stock RFT are way Expensive !!

[acerboo]

inner tyre wear a huge problem over here has been suggested that less camber will help but no one seems to have had it done although im thinking about it as im sick of dumping perfectly good tyres just because the inner has worn out, personally i think its bridgestone rubbish tyres.

[onefastman]

Im interested but wont do it as I track my car.

[timhatimay]

When I got my car aligned (at a european race shop), I spoke with the owner for a while. He used to work at a BMW dealership for several years (and also a Porsche, audi, etc.), and was also an accomplished racer. He mentioned that BMW's typically have quite high camber stock in the rear. If you notice the spec on our cars is somewhere around -1.8*. He said that when he worked at the dealership, he would often set the rear camber lower than the stock spec for this very reason. If you don't drive aggressively on the street or drive at any high performance events, you could probably get more life from the tires using less camber. Thats why per his suggestion, the alignment specs should always be based upon the persons driving style and habits not necessarily the stock specifications. I wore out the outside edges of my tires, so I had the opposite problem.

Tim

[MarkRacerX]

One guy I know dismounts his rears and flip/flops them so now the worn portion is on the outter and the inner still has plenty of life. Kinda a pita but you get more tire life out of it. Just seems weird on a stock suspension car, I remember back in the day slamming Honda's and w/ out camber kit insides would wear crazy, but this is Stock w/ so much rear camber to eat tires...

Yeah I hear you there, if you track it - want best handling setup..but for a DD I bet I wouldn't even hardly notice rear camber adjusted.

[fisherbln]

Less camber will definitely increase tire life in the rear. BMW sets up the car to be driven hard and most people don't drive hard enough for the level or rear camber they have set at stock. I don't know about an extra 15K miles, but you'll definitely add quite a few.

If you take corners and exit ramps at very high speeds for fun, I'd keep the stock rear camber. If not, I'd reduce it to increase tire life. You won't feel a difference.

[rothwem]

So heres a dumb car dynamics question: If you decrease the camber in the rear without decreasing the camber in the front, would you then have more grip on the front, causing a tendancy towards more oversteer?

[mike-y]

Originally Posted by msrothwell

So heres a dumb car dynamics question: If you decrease the camber in the rear without decreasing the camber in the front, would you then have more grip on the front, causing a tendancy towards more oversteer?

yes, but bmws are setup to understeer inherently, so you'll be fine. Especially if you are running staggered tires.

[acerboo]

you cant change the rear tyres fron side to side as they are directional

[2 3pair]

Originally Posted by acerboo

you cant change the rear tyres fron side to side as they are directional

Yes you can, as long as they're not directional AND asymmetric

[subieworx]

toe is the cause of the tire wear in the rear not camber. The stock spec of about -1.8* of camber is not much at all. Most newer cars run about this much in the rear. The problem comes when you add +.2* of toe per side. Toe is the rolling equivalent of dragging a tire sidewise which is obviously bad for wear. You can run up to 3.5* of camber with little affect on tire wear if you rotate somewhat frequently and run 0* of toe.

[rothwem]

Originally Posted by subieworx

toe is the cause of the tire wear in the rear not camber. The stock spec of about -1.8* of camber is not much at all. Most newer cars run about this much in the rear. The problem comes when you add +.2* of toe per side. Toe is the rolling equivalent of dragging a tire sidewise which is obviously bad for wear. You can run up to 3.5* of camber with little affect on tire wear if you rotate somewhat frequently and run 0* of toe.

You're partially right. The toe wears the tire on the outside, the camber wears on the inside. So to get even tire wear, you add a bit of toe with your camber. If you do 3.5 degrees negative camber, and no toe, you'll wear preferentially on the inside and the outside will never wear.

toe also hurts gas mileage, I wonder if less camber and less toe would result in a more neutral car with better mileage...

[David1]

Originally Posted by subieworx

toe is the cause of the tire wear in the rear not camber. The stock spec of about -1.8* of camber is not much at all. Most newer cars run about this much in the rear. The problem comes when you add +.2* of toe per side. Toe is the rolling equivalent of dragging a tire sidewise which is obviously bad for wear. You can run up to 3.5* of camber with little affect on tire wear if you rotate somewhat frequently and run 0* of toe.

Camber does wear a tire. Period. But toe out will exellerate inboard wear and toe in will wear the outboard of the tire quicker. Most other cars (I have aligned them all, run less than 1 degree of negative camber out back and less than .5 negative camber up front. Take a tire with 1.8 negative camber, zero toe, and run it straight with no turning ever and the inside will wear faster period. Tire wear is a factor of all alignment settings, suspension geometry, tire compounds, road conditions, and driving style.

[mike-y]

there is wear with negative camber, but it is minimal if toe is zeroed out. I ran -2 degrees camber on my old integra (up front) for a few years, and never had a problem with bad wear. sure, the inside of the front tires was very slightly more worn than the outside, but it was negligible. Basically, when the inside part of the tread was bald, the outside treads was down to the wear bars.

And if you ever track your car, you'll wear the outside treads a lot more than the insides with anything less than -3.5 degrees camber anyway.

[subieworx]

Originally Posted by David1

Camber does wear a tire. Period. But toe out will exellerate inboard wear and toe in will wear the outboard of the tire quicker. Most other cars (I have aligned them all, run less than 1 degree of negative camber out back and less than .5 negative camber up front. Take a tire with 1.8 negative camber, zero toe, and run it straight with no turning ever and the inside will wear faster period. Tire wear is a factor of all alignment settings, suspension geometry, tire compounds, road conditions, and driving style.

Yes, but your example is flawed as that will never happen. I have also aligned many cars and can say that toe will wear tires significantly faster than camber. Camber is definitely a wear angle, but no where close to toe. It just so happens that camber is easier to see than toe which is why most people attribute tire wear to it. I know where you're coming from though.

[acerboo]

take the point on camber and toe but all the problems are with inside rear tyre wear and very rapid wear at that, it has been suggested that the make up of the bridgestone tyres combined with the camber is accelerating the wear. surely easing the camber will help, at the same time not all these cars can be aligned with incorrect toe from new?

[subieworx]

lessen the camber and toe a bit. It will make the car more tail happy, but will prolong tire life. I have been very happy with about -1.3* of camber and .1 toe in per side.

[David1]

If you are worried about tire wear, you bought the wrong car. I would not make my car looser just to get a few thousand more miles out of the tires and that's all were talking about saving here in the end. Better solution would be to keep the factory settings and buy lower performing tires that have a higher treadwear rating and less grip. I on the other hand only expect to get 8k-9k miles out of the rears and 12k out of the fronts from "driving" the car.

[2 3pair]

Originally Posted by David1

If you are worried about tire wear, you bought the wrong car. I would not make my car looser just to get a few thousand more miles out of the tires and that's all were talking about saving here in the end. Better solution would be to keep the factory settings and buy lower performing tires that have a higher treadwear rating and less grip. I on the other hand only expect to get 8k-9k miles out of the rears and 12k out of the fronts from "driving" the car.

So I can feel pretty good that the original owner of my car got 17,000 out of the rears (Goodyear GS-D3s). He probably drove pretty conservatively.

[David1]

Originally Posted by 2 3pair

So I can feel pretty good that the original owner of my car got 17,000 out of the rears (Goodyear GS-D3s). He probably drove pretty conservatively.

I got 8k miles out of GSD3's on the rear of my other 335, (I am not stock)But, it was the most evenly worn set I had. You should get about 20k out the fronts. My 09 is getting better wear out of the rears (PS2) that have a lesser treadwear rating and I am running more camber on the newer one. I think some of reason for the better tire life on the back of my 09(I drive with DTC always on) is due to the better E-diff set up than my 07.

[MarkRacerX]

Yeah my camber was off very minor, but did have some rear toe issues..that ok, that stockers were done anyways, I just wanted to play it safe w/ alignment since I just bought the car and ordered new wheels/tires.

Thanks for info. I kept w/ the norm BMW specs.

Mark