Does the macadem road surface have a great effect on tire wear?

Does the macadam road surface have a great effect on tire wear?
<https://i.postimg.cc/KYXHVC3n/mount32.jpg>

In a previous thread, we discussed tire wear on downhill slow speed (less
nominally around 30mph) steering lock to steering lock twisties due to
suspension geometries (e.g., camber scrub on the outside edge of the inside
tire due to positive caster induced from SAI+IA, with a correspondingly
confusing negative force-vector related camber on that same inside wheel).
<https://i.postimg.cc/T1HkcsX5/mount31.jpg>

When I mentioned that to neighbors, they told me that they considered their
high tire wear due to the road surface being not all that smooth.

The road surface happens to be not of the best quality, in that it's
certainly not "packed" as well as a highway would be, such that, even at
times, I've seen mushrooms pop up out of two inches of macadam.

If we assume the road surface isn't well packed, the question is whether
tire wear is "appreciably" affected by that road surface?

I didn't see anything in the Gillespie bible on the subject, but I didn't
read every page because my head was already spinning just by looking at the
diagrams.

Does the macadam road surface have a great effect on tire wear?

In alt.home.repair, on Tue, 25 Jun 2019 17:28:34 -0000 (UTC), "Arlen G.
Holder" > wrote:

>Does the macadam road surface have a great effect on tire wear?
><https://i.postimg.cc/KYXHVC3n/mount32.jpg>
>
>In a previous thread, we discussed tire wear on downhill slow speed (less
>nominally around 30mph) steering lock to steering lock twisties due to
>suspension geometries (e.g., camber scrub on the outside edge of the inside
>tire due to positive caster induced from SAI+IA, with a correspondingly
>confusing negative force-vector related camber on that same inside wheel).
><https://i.postimg.cc/T1HkcsX5/mount31.jpg>

The one of the right front corner shows that you need a wheel alignment.



>When I mentioned that to neighbors, they told me that they considered their
>high tire wear due to the road surface being not all that smooth.
>
>The road surface happens to be not of the best quality, in that it's
>certainly not "packed" as well as a highway would be, such that, even at
>times, I've seen mushrooms pop up out of two inches of macadam.
>
>If we assume the road surface isn't well packed, the question is whether
>tire wear is "appreciably" affected by that road surface?
>
>I didn't see anything in the Gillespie bible on the subject, but I didn't
>read every page because my head was already spinning just by looking at the
>diagrams.
>
>Does the macadam road surface have a great effect on tire wear?

On Tue, 25 Jun 2019 14:38:43 -0400, micky wrote:

> The one of the right front corner shows that you need a wheel alignment.

It's my fault for showing the tires, where all I wanted to show was the
pavement. I'll snap a photo of _just_ the pavement separately, where for te
purpose of this thread, we can ignore the vehicle itself in that photo.

I understand that it _looks_ like an alignment problem in that photo, but
this happens to _many_ of the cars on this mountain, and, in particular,
this vehicle has been professionally aligned by BMW themselves so I can
only conclude that the alignment is ok.

Xeno, in another thread, showed this picture, which, I think, is really
what's happening in turns, but that's discussed elsewhe
<https://www.gmforum.com/attachments/buick-172/10333d1369664321-too-much-positive-camber-after-strut-replacement-parkavenuepassengerrsidepositivecamber1.jpg>

The only reason for this picture in the OP was to show the road surface.
<https://i.postimg.cc/T1HkcsX5/mount31.jpg.

Please ignore the vehicle.

The thread on that specific "camber scrub" is over he
o Clare - are smaller car tires easier to balance than SUV tires?
<https://groups.google.com/forum/#!topic/alt.home.repair/So4om4fLtmI>

And partly here too
o How would you run a lateral acceleration test in a vehicle on twisty roads at no more than 40mph?
<https://groups.google.com/forum/#!topic/comp.mobile.android/KVM5JB5M15c>

Where, on turns, a specific "camber scrub" is occurring (we think):
<https://i.postimg.cc/vZs6Vm3B/mount35.jpg>

In contrast to that problem set, _this_ thread, is only about how much
effect the macadam road surface has on tire wear.
<https://i.postimg.cc/KYXHVC3n/mount32.jpg>

On Tue, 25 Jun 2019 18:36:11 -0400, Frank wrote:

> Macadam is a little rougher than asphalt and more abrasive surface will
> give more wear but stuff I read did not quantified amount of wear.


Thanks Frank, where I never knew there was a difference between Macadam and
asphalt.

What would you call this stuff I just showed Clare?
<https://i.postimg.cc/SNJHYT9s/mount45.jpg>

> Tire rotation and alignment are probably much more important.

The problem is that these vehicles ALL have the same wear patterns to the
OUTSIDE edge, where a tire "rotation" won't help unless we flip the tire on
the rim, am I right?

BMW: <https://i.postimg.cc/g004XCLW/mount37.jpg>
Lexus: <https://i.postimg.cc/8zVxVHVx/mount40.jpg>
Toyota: <https://i.postimg.cc/pT71cQZG/mount41.jpg>

All are aligned and owned by different people, which averages out the
driving habits, wouldn't you think?

The only common factor is the road.
o Either the surface (or crown) <https://i.postimg.cc/pX44ffQB/mount46.jpg>
o The shape of the road <https://i.postimg.cc/kGhZh80q/mount44.jpg>

The main question here is what effect the road SURFACE has on this wear?

On Tue, 25 Jun 2019 14:09:54 -0700 (PDT), Thomas wrote:

> It is the reason for wear. If you never turned all 4 tires would wear evenly.
> I never turn the wheels in park. Pure friction.
> I only start to turn when in motion. I actually think about it.

Hi Thomas,

Thanks for the advice to "not turn", which, well, which might be a little
problematic, given that this is a typical turn where the steering wheel
goes from lock to lock at a reasonably steep incline.
<https://i.postimg.cc/kGhZh80q/mount44.jpg>

On Tue, 25 Jun 2019 17:23:21 -0400, Clare Snyder wrote:

> Looks like pretty decent ASPHALT to me.
> Definitely not "Macadam" - or tar and chip.

Hi Clare,
Thanks for suggesting that where I always "assumed" macadam and Asphalt
were the "same" thing, but where you make a distinction, which I
appreciate, and where this is the overall surface at the moment:
<https://i.postimg.cc/T1PF9QHt/mount43.jpg>

Here's a snapshot of the "layers" that I took this morning for you:
<https://i.postimg.cc/SNJHYT9s/mount45.jpg>

Some people called the lower layers "chip seal", where I'm a bit confused
as to how people use the terms "asphalt" and "macadam" but I'm using it
interchangeably (our of ignorance).
<https://wikidiff.com/asphalt/macadam>

Nonetheless, the question is whether _this_ road surface is having any
major effect on the wear of the tires given the road is windy and steep
such that the trucks gouge many of the corners like claws scraping at the
surface.
<https://i.postimg.cc/pX44ffQB/mount46.jpg>

While the road surface is pretty smooth where many of the turns are almost
unnoticeable, such as this gradual almost flat curve
<https://i.postimg.cc/wxf5CyS6/mount42.jpg>

Some of the turns you do notice though, such as this basic hairpin:
<https://i.postimg.cc/kGhZh80q/mount44.jpg>

The end result of either the curves or the road, is this type of one-way
unidirectional feathering on the outside edge of the front tires:
<https://i.postimg.cc/pT71cQZG/mount41.jpg>

It doesn't only happen to my vehicles, as I've inspected quite a few, such
as this Lexus SUV today.
<https://i.postimg.cc/G3HWPtQg/mount39.jpg>

Do you think the MAJOR contributor to this Lexus SUV wear has much (if
anything) to do with the coarseness of the road surface?
<https://i.postimg.cc/8zVxVHVx/mount40.jpg>

It seems to be the same as this BMW SUV wear, doesn't it?
<https://i.postimg.cc/g004XCLW/mount37.jpg>

Both are impeccably maintained by the stealer, and both travel the same
road where, the diagnostic goal is to figure out whether the road surface
has any appreciable effect on the reputed "camber scrub" we've been
discussing.
<https://i.postimg.cc/wTf1xnzJ/mount36.jpg>

Asphalt('black top') exists primarily for one rea$on....