Run flat tires

[master1917]

Originally Posted by Crowz

Im not sure what all sizes they come in. They had the highest treadware rating of the run flats that I looked at but none of the rf tires has any real tread life warranty to them. They are also all season tires. Grip has been pretty good and they ride smooth.

Thanks, I do have winter Continentals RF on 19 inch rims - just bought them, still in the shop with refinished rims! So now looking for dedicated summers nit all seasons. As of now thinking non-RF Conti Sport. Also thought non-RF Micheline Pilot 4 but those 500 dollars. Seems too big of a difference.

Having bought a car with 2 sets if wheels 6 months ago I didnt expect to drop 4 grands on tires so fast!!! Crazy!

[ard]

Originally Posted by Big Smoke

Sorry for offending you ard. I'm not going to quote any numbers. Just suggesting that there are many points of view. I'm not giving any advise, just pointing out there are options.
On one of my vehicles, they suggested a "four wheel alignment", I later found out, that the rear is not adjustable. So are they adjusting to what? just to line up with the back? I do my best to research, to the best of my knowledge. How is sharing a question, bad advise?

https://www.tirerack.com/tires/tiret...e.jsp?techid=4

from tire rack sight. Not my poppy cock.

"If you are a reserved driver, aligning your vehicle to the vehicle manufacturer's preferred settings is appropriate.

If you are an assertive driver who enjoys driving hard through the corners and expressway ramps, a performance alignment is appropriate for your car. A performance alignment consists of using the vehicle manufacturer's range of alignment specifications to maximize the tires' performance. A performance alignment calls for the manufacturer's maximum negative camber, maximum positive caster, and preferred toe settings. While remaining within the vehicle manufacturer's recommendations, these alignment settings will maximize tire performance."

1. Who DOESN'T get a '4 wheel alignment'?!? Duh, of course

2. You dont get to cite internet drivel....there is no 'preferred toe setting' from BMW.

The are talking out of both sides of their mouths: 'set it to the preferred settings" and also "set it in the mfgs range"

BMW HAS ONE SET OF SPECS! They have no "preferred" settings

You wont quote numbers yet you will assert your recommendations are accurate.

3. I say set it mid spec on caster and camber. If you experts feel this isnt aggressive enough for your "freeway on ramps" set it at max. You will not be able to feel the difference.

[master1917]

Originally Posted by ard

1. Who DOESN'T get a '4 wheel alignment'?!? Duh, of course

2. You dont get to cite internet drivel....there is no 'preferred toe setting' from BMW.

The are talking out of both sides of their mouths: 'set it to the preferred settings" and also "set it in the mfgs range"

BMW HAS ONE SET OF SPECS! They have no "preferred" settings

You wont quote numbers yet you will assert your recommendations are accurate.

3. I say set it mid spec on caster and camber. If you experts feel this isnt aggressive enough for your "freeway on ramps" set it at max. You will not be able to feel the difference.

Ard, can you please clarify the 3 above. I thought I should specify the toe numbers of .02 only. Is camber and caster also adjustable on X5M E70? I have seen posts about camber on the fronts being not adjustable and greatly contributing to outside edge wear.

PS I am not knowledgeable on any of it as all this topic is new to me as I started kooking into it 2 days ago on my way from Florida when I noticed my fronts outside edges are disappearing so bear with me please...

[ard]

Originally Posted by master1917

Ard, can you please clarify the 3 above. I thought I should specify the toe numbers of .02 only. Is camber and caster also adjustable on X5M E70? I have seen posts about camber on the fronts being not adjustable and greatly contributing to outside edge wear.

PS I am not knowledgeable on any of it as all this topic is new to me as I started kooking into it 2 days ago on my way from Florida when I noticed my fronts outside edges are disappearing so bear with me please...

Sure.

Caster is not really adjustable.

Camber can be 'adjusted' in the front with different control arms, so for all practical purposes it is set too. I dont recall if messing with the upper mount on the strut will get you anything.

Toe is adjustable front and rear

Camber is fully adjustable in the rear.

Here is a key:

yes, cambering a tire will create more 'pressure' on ne edge tor the other. This is conceptually easy to understasnd- 'the inner edge is wearing, that cause the wheel is cambered pushing that inner edge down'

WHAT IS NOT OBVIOUS is that 'toe' acts as a 'compounder': the tire is cambered, but then the toe acts to scrub that edge even more than if it had not been cambered.

Since we really have limits on camber- and in fact you DO want camber to help stabilize cornering- then back the toe down to almost zero. 0.01 or 0.02.

I have a track prepped 996TT, on which ive run some interesting alignments... but this can be corner balanced for pressure, and camber, caster and toe are all independently adjustable (as is shock compression and rebound)...the point being tat the E70 simply is not a race car, it doesnt have the adjustments a track car has, it doenst have the tires, suspension or get driven at track speeds. The silly "aggressive driver/freeway offramp" language that I have seen for years is simply a disservice to the majority of X5 drivers. VAST majority. Everyone wants to think they are a BMW race car driver. We arent. I mean shops will repeat all kinds of old wives tales they really truly believe: BMWs are set aggressive, just the way they are- they eat tires. or 'set it mid spec, BMW engineers do it on purpose...or the ol' 'gotta pay to play'...the list never ends.

I will come back to the fact that I give very specific numbers and do this for a reason and a rationale. To come here and say "ard is wrong", yet to offer up 'one size fits all ricerboi platitudes' about aggressive or performance alignments...and you cannot provide a SPECIFIC ALIGNMENT NUMBER SETTING on the E70 X5 to achieve this 'performance setting' is BS.

[master1917]

Originally Posted by ard

Sure.

Caster is not really adjustable.

Camber can be 'adjusted' in the front with different control arms, so for all practical purposes it is set too. I dont recall if messing with the upper mount on the strut will get you anything.

Toe is adjustable front and rear

Camber is fully adjustable in the rear.

Here is a key:

yes, cambering a tire will create more 'pressure' on ne edge tor the other. This is conceptually easy to understasnd- 'the inner edge is wearing, that cause the wheel is cambered pushing that inner edge down'

WHAT IS NOT OBVIOUS is that 'toe' acts as a 'compounder': the tire is cambered, but then the toe acts to scrub that edge even more than if it had not been cambered.

Since we really have limits on camber- and in fact you DO want camber to help stabilize cornering- then back the toe down to almost zero. 0.01 or 0.02.

I have a track prepped 996TT, on which ive run some interesting alignments... but this can be corner balanced for pressure, and camber, caster and toe are all independently adjustable (as is shock compression and rebound)...the point being tat the E70 simply is not a race car, it doesnt have the adjustments a track car has, it doenst have the tires, suspension or get driven at track speeds. The silly "aggressive driver/freeway offramp" language that I have seen for years is simply a disservice to the majority of X5 drivers. VAST majority. Everyone wants to think they are a BMW race car driver. We arent. I mean shops will repeat all kinds of old wives tales they really truly believe: BMWs are set aggressive, just the way they are- they eat tires. or 'set it mid spec, BMW engineers do it on purpose...or the ol' 'gotta pay to play'...the list never ends.

I will come back to the fact that I give very specific numbers and do this for a reason and a rationale. To come here and say "ard is wrong", yet to offer up 'one size fits all ricerboi platitudes' about aggressive or performance alignments...and you cannot provide a SPECIFIC ALIGNMENT NUMBER SETTING on the E70 X5 to achieve this 'performance setting' is BS.

Thanks ard, so now I am clear that for a longer tire life, the E70 X5M, the camber in the rear must be mid range of the specs and the toe for both front and rear must be at either +0.01 or +0.02. These values must be the same per axel but may differ between the front and rear axels like +0.01 upfront and +0.02 in the rear or the other way around.

PS I am surprised my fronts are gone before rears. Rears look great. Fronts are gone.

[SeanC]

Originally Posted by Tomaz

Your advise is not bad and is in fact correct. As for the 4 wheel alignment the X5 is definitely able to be aligned on all 4 corners. I had my rear camber adjusted from the factory set negative 1.5° to as close to neutral as possible to reduce inner tire wear.

I'm willing to bet, assuming that the alignment is correct, the inner tire wear on the rears is due to the factory inflation specs of the runflats. Run them around 40psi+ and you'll eliminate the possibility of rear inner tire wear.

[master1917]

Update
Just had 4 brand new non-RF Continental Extreme Contact Sport installed an hour ago for CAD 1,700 all in. Hope these will last at least 30k kms...
Drove home about 25 kms before going for alignment tomorrow. So far disappointed by loud tire noise. I went non-RF as expected a quiet ride - so far its rather loud.
The yellow stripes on the fronts outside edges already gone - must be big alignment problem, but the car goes straight.

Brought my 2 rear 315 RF Bridgestones HP Dueler with me as they are still very good.

Hope $2k tires will last a few seasons...the concept of multi-thousand dollar tire sets not lasting a couple of years is very new to me!

[Crowz]

Originally Posted by master1917

Update
Just had 4 brand new non-RF Continental Extreme Contact Sport installed an hour ago for CAD 1,700 all in. Hope these will last at least 30k kms...
Drove home about 25 kms before going for alignment tomorrow. So far disappointed by loud tire noise. I went non-RF as expected a quiet ride - so far its rather loud. The yellow stripes on the fronts outside edges already gone - must be big alignment problem, but the car goes straight.

Brought my 2 rear 315 RF Bridgestones HP Dueler with me as they are still very good.

Hope $2k tires will last a few seasons...

Ouch. My Pirelli's run flats were $800 for all 4 tires. Silent and smooth.

[master1917]

Originally Posted by Crowz

Ouch. My Pirelli's run flats were $800 for all 4 tires. Silent and smooth.

Unfortunately, CAD 800 buys just one Pirelli RFT in Toronto)))

[ard]

Originally Posted by SeanC

I'm willing to bet, assuming that the alignment is correct, the inner tire wear on the rears is due to the factory inflation specs of the runflats. Run them around 40psi+ and you'll eliminate the possibility of rear inner tire wear.

I tend to run higher pressures that 'recommended'...especially on the fronts. not 40+, but 38ish.

Be very interested to hear what OPs alignment is at, initially. Hopefully that info tells a coherent 'story'