Is it just BMW that does not recommend tire rotation?

RichieP wrote:

> "ray" > wrote in message
> ...
>
>>Steve wrote:
>>
>>>Shaft Drive wrote:
>>>
>
> SNIP
>
>
>>I think the Acura NSX had a unique tire at each corner as well.
>
>
> Forgive my ignorance but, in using the word 'unique' are saying that each
> tire is actually manufactured differently? And if so, how does one replace
> a single tire? Do you request a left rear, front right, etc...?
>
> RichieP

No, but when you have different size front and rear tires in combination
with unidiriectional tires, then a MOUNTED tire/wheel combo is unique to
each corner of the car. You COULD dismount the front tires and swap them
side to side and re-mount them, but SHEESH! Why bother?

Timothy J. Lee wrote:

> In article >,
> zerouali > wrote:
>
>>Tyre rotation seems to be a mainly American thing, no one else ever really
>>mentions or uses it, as far as I've seen. Any particular reason for this?
>

It all depends on what you're trying to maximize.

If you're trying to extract the utomost performance from every tire,
then don't rotate because once a wear pattern is established, switching
it to a different corner of the car would result in a sub-optimal
contact patch.

On the other hand, if you don't expect to push your car to its absolute
lateral G limit all the time (as in the case of 99.9% of daily driven
cars!) then rotating the tires and tolerating a slightly sub-optimum
contact patch right after rotation WILL get longer service life out of
each tire.

The vast majority of cars on the road- ESPECIALLY front-drive vehicles-
benefit a lot from tire rotation in the long run.

In article >,
Dan > wrote:
> Can you point me to the BMW site the recommends no tire rotation?

Says so in my driver's handbook.

--
*Someday, we'll look back on this, laugh nervously and change the subject

Dave Plowman London SW
To e-mail, change noise into sound.

fbloogyudsr wrote:
> "RichieP" > wrote
> > "ray" > wrote
> >> Steve wrote:
> >> > Shaft Drive wrote:
> >
> >> I think the Acura NSX had a unique tire at each corner as well.
> >
> > Forgive my ignorance but, in using the word 'unique' are saying
that each
> > tire is actually manufactured differently? And if so, how does one

> > replace
> > a single tire? Do you request a left rear, front right, etc...?
>
> That is exactly the case. The NSX (and many other high performance
> cars, including BMW's with different-sized front/rear sport packages)
> have uni-directional tires. That means that the tires can be on only
> one side (left/right) of the car. When, in addition, the tires at
the
> front and rear are different sizes, that means that no tire can be
> used *EXCEPT* at the corner it is designed for. The NSX ('91-'94)
> has 205/50ZR15's front, 225/50ZR16 rear (IIRC), and the OEM
> tires (Yoko & Bridgestones) are uni-directional.

There are all sorts of wacky configurations. My current Pirelli
PZero Nero M+S tires are non-directional asymmetric. Some tires
are directional asymmetric. The wackiest of all are directional
asymmetric left/right specific.

<http://www.tirerack.com/tires/tires.jsp?tireMake=BFGoodrich&tireModel=g-Force+T%2FA+KD>

On 16 May 2005 15:14:08 -0700, "y_p_w" > wrote:

>There are all sorts of wacky configurations. My current Pirelli
>PZero Nero M+S tires are non-directional asymmetric. Some tires
>are directional asymmetric. The wackiest of all are directional
>asymmetric left/right specific.

Yep. Like the NSX. A different tire on each corner. It's not that
bad once you get used to the idea.
--
Dan.

fbloogyudsr wrote:
> "zerouali" > wrote
>
>> Tyre rotation seems to be a mainly American thing, no one else ever
>> really mentions or uses it, as far as I've seen. Any particular reason
>> for this?
>
>
> The main rationale is to maximize tire mileage/life. On a FWD car, the
> fronts always wear more and won't last as long as the rears. On a RWD
> car, the rears wear more. And the spare tire doesn't wear at all.

Well, sort of... I've said this before, but I'll say it once more;
Rotating tires is is not, not has it ever been, about increasing the
total mileage of a tire, *except* when considered as a set.

By rotating tires one can even out the wear at the 4 corners and thereby
equalize the wear so that the set of 4 all wear-out at the same time.

Or to state it another way, it will not extend the life of any single
tire, but rather will allow the 4 to be spent at the same time and be
replaced as a set.

The value in that is especially evident when considering how often a
particular tire model is obsoleted and replaced with a new one in any
particular brand.

Some folks advocate replacement of the spare tire after a certain amount
of age regardless of how much wear it has attained, for safety reasons.
Obviously, any scheme that allows the spare into the rotation will
extend the life of the "set" by ~20%.

OTOH, if you have a brand/model of tire that is readily available over a
long time period (or if you wear them out quickly due to high annual
mileage) just replacing the axle that wear quickest would be equally as
economical as replacing the set.

-Fred W

-Fred W

Steve wrote:
> Timothy J. Lee wrote:
>
>> In article >,
>> zerouali > wrote:
>>
>>> Tyre rotation seems to be a mainly American thing, no one else ever
>>> really mentions or uses it, as far as I've seen. Any particular
>>> reason for this?
>>
>>
>
> It all depends on what you're trying to maximize.
>
> If you're trying to extract the utomost performance from every tire,
> then don't rotate because once a wear pattern is established, switching
> it to a different corner of the car would result in a sub-optimal
> contact patch.
>
> On the other hand, if you don't expect to push your car to its absolute
> lateral G limit all the time (as in the case of 99.9% of daily driven
> cars!) then rotating the tires and tolerating a slightly sub-optimum
> contact patch right after rotation WILL get longer service life out of
> each tire.

I don't uderstand the theory of this statement. If you are running a
tire which has worn a particular way, and now has a sub-optimal contact,
wouldn't you think that the "high spots" (the areas with greater
pressure in the new location) would wear faster and therfore negate the
total tire life assertion?

-Fred W

Malt_Hound wrote:

> Steve wrote:
>
>> Timothy J. Lee wrote:
>>
>>> In article >,
>>> zerouali > wrote:
>>>
>>>> Tyre rotation seems to be a mainly American thing, no one else ever
>>>> really mentions or uses it, as far as I've seen. Any particular
>>>> reason for this?
>>>
>>>
>>>
>>
>> It all depends on what you're trying to maximize.
>>
>> If you're trying to extract the utomost performance from every tire,
>> then don't rotate because once a wear pattern is established,
>> switching it to a different corner of the car would result in a
>> sub-optimal contact patch.
>>
>> On the other hand, if you don't expect to push your car to its
>> absolute lateral G limit all the time (as in the case of 99.9% of
>> daily driven cars!) then rotating the tires and tolerating a slightly
>> sub-optimum contact patch right after rotation WILL get longer service
>> life out of each tire.
>
>
> I don't uderstand the theory of this statement. If you are running a
> tire which has worn a particular way, and now has a sub-optimal contact,
> wouldn't you think that the "high spots" (the areas with greater
> pressure in the new location) would wear faster and therfore negate the
> total tire life assertion?
>
> -Fred W

Yes, but the tire thus lasts longer than it would if you left it where
it was so that it wore through to the cord in the first high-wear area.

Frankly, most cars don't wear tires that badly except some FWD vehicles.
Its entirely possible to wear two sets of front tires on an FWD down
to the wear indicators without showing significant overall wear on a
single set of rear tires. But by that time the rear tires are so aged
that they don't have the grip they should and are subject to tread
separation and other problems. It seems to me, based on several
experiences now, that modern tire designs are more sensitive to the
aging of the rubber compounds than the tires of the 70s. Even if you had
a set of tires stored in a dark, dry garage for 6 years, the odds of
them lasting a full lifetime when you put them on the car will be VERY
small- they'll probably develop cracks or separations long before they
wear out.

Dean Dark wrote:
> On 16 May 2005 15:14:08 -0700, "y_p_w" > wrote:
>
>
>>There are all sorts of wacky configurations. My current Pirelli
>>PZero Nero M+S tires are non-directional asymmetric. Some tires
>>are directional asymmetric. The wackiest of all are directional
>>asymmetric left/right specific.
>
>
> Yep. Like the NSX. A different tire on each corner. It's not that
> bad once you get used to the idea.

It's highly optimized for handling purposes, and if you think about it,
the front tires are doing different work than the rears, so it makes
sense from a performance point of view. The outside of the tire also
does different work than the inside...

But yeah, it can kinda suck if you get a nail in one tire and they
happen to be back ordered on the left front tire for two weeks... and
your only spare is the donut... especially because cars like Vettes look
absolutely silly on the spare. Imagine a Viper with two donuts on the
back.... now imagine trying to drive it.

ray wrote:

> Dean Dark wrote:
>
>> On 16 May 2005 15:14:08 -0700, "y_p_w" > wrote:
>>
>>
>>> There are all sorts of wacky configurations. My current Pirelli
>>> PZero Nero M+S tires are non-directional asymmetric. Some tires
>>> are directional asymmetric. The wackiest of all are directional
>>> asymmetric left/right specific.
>>
>>
>>
>> Yep. Like the NSX. A different tire on each corner. It's not that
>> bad once you get used to the idea.
>
>
> It's highly optimized for handling purposes, and if you think about it,
> the front tires are doing different work than the rears, so it makes
> sense from a performance point of view. The outside of the tire also
> does different work than the inside...
>
> But yeah, it can kinda suck if you get a nail in one tire and they
> happen to be back ordered on the left front tire for two weeks... and
> your only spare is the donut... especially because cars like Vettes look
> absolutely silly on the spare. Imagine a Viper with two donuts on the
> back.... now imagine trying to drive it.

That's just one of the reasons why most people who own them never use
either a Viper or NSX for basic transportation without a backup car.
Worse than that, imagine getting a flat on a cross-country trip in the
middle of nowhere...