Tire life

Hi,

I need advice about assessing tire quality from the experts/ gurus in
this forum.

With regards to tire composition and characteristics, what are the
important things I need to look out for when assessing quality of an
unbranded tire. Assuming that the tires are used in the recommended way
( such as not over loading or over speeding), I have heard that there
are several characteristics of tires which make them last longer, and I
am hoping you can shed some light on the following:

Thread depth - Does the tire last longer if it has a deeper thread?

Ply Rating - Is there any disadvantage to having a high ply rating,
and is there any specific correlation between the number of plys and
the weight. (for example each ply should add x kgs to the weight.)?

Quality of rubber - Is there variation in quality of rubber that can
make a tire last longer. Do they mix rubber with anything to increase
durability?

Tire patterns - what are the advantages and disadvantages of using a
rib/lug/mix designs

Weight of the tire - If it is a heavy tire would it last longer
assuming that there is more rubber used.

Sidewall - what is the difference between good quality and bad
quality sidewall?

The weather condition here is very hot, dry and sandy most of the year
with 4 months of moderate rain. So even the well built roads tend to be
very sandy which I assume increases tire friction. Some of the areas I
travel through are very underdeveloped with a lot of pot holes on the
roads. I have heard that nylon/x-ply/bias tires are better then radials
for uneven road surfaces and radials are better for good road
conditions, is this true?

Thank you for your help,
James

On Wed, 21 Sep 2005, wrote:

> With regards to tire composition and characteristics, what are the
> important things I need to look out for when assessing quality of an
> unbranded tire.

Unbranded tires are unbranded because the company who made them does not
wish their reputation to be harmed by being associated with that
particular tire, or because that particular tire was made in a backalley
shop in China that was told by an unscrupulous Western importer "Make them
black and round". The "quality" of an unbranded tire is...there's no such
thing.

Tire sales are always going on. You don't have to spend a fortune. Buying
****ty tires is playing with lives (your own and others on the road).

Hi Daniel,

Sorry when I said unbranded I ment a brand that is not yet famous. I
hope you understand. I know that it could be dangerous trying something
new, this is why I am trying to find out what I should know about new
brands tires to minimise the risk. Apart from the making sure they have
E mark, Dot and ISO certified.

Thanks,
James

Daniel J. Stern wrote:
> On Wed, 21 Sep 2005, wrote:
>
> > With regards to tire composition and characteristics, what are the
> > important things I need to look out for when assessing quality of an
> > unbranded tire.
>
> Unbranded tires are unbranded because the company who made them does not
> wish their reputation to be harmed by being associated with that
> particular tire, or because that particular tire was made in a backalley
> shop in China that was told by an unscrupulous Western importer "Make them
> black and round". The "quality" of an unbranded tire is...there's no such
> thing.
>
> Tire sales are always going on. You don't have to spend a fortune. Buying
> ****ty tires is playing with lives (your own and others on the road).

Be more specific about the tire brand.

Richard.

So much of our education about tires comes from suspect sources such as
advertising or opinionated consumers. A good situation is when you are on
the knowledge continuum regarding a subject with understandable limits;
then you can gage your ignorance more accurately. With tires, I admit both
ignorance and, to a great extent, a lack of understanding of the boundaries
of tire technology.

I've posted a couple of times in different forums with regard to this
subject. In doing so, as now, I am fishing for someone with the knowledge I
clearly lack to educate me about tires. So far, the only feedback I have
received were emotional responses (and some rants) with no understandable
substance. What I would like is more of an engineer-to-engineer response
that deals with physical properties such as friction, stress loading,
compounds, etc. The request remains open; I am always willing to be
educated.

Since the mind abhors a vacuum, I postulated my own assessment of tires. The
basis of this assessment is that there is little to assess. Here are my
thoughts on the subject, FWIW:

Buy from someone who has, at least, an economic or relationship stake in the
transaction. This means you have a place to go to should the tire deal turn
out rotten. So far, in buying more sets of tires for more cars than I care
to remember, I have only had to go back once to replace a faulty new tire
that only held air for about an hour. Once replaced, the set ran the
anticipated 40K miles or so.

Buy on price. Go cheap. Why not? When is the last time you received input
from your auto insurance company (who has a vested interest in you not
crashing) with any sort of guidance regarding tires. I'll bet the answer is
"never". That's because there is nothing to alert you about. The tires will
go 30 or 40 thousand miles; if they don't, exercise whatever warranty you
get with the dealer who has an interest in keeping you satisfied.

Pay attention to the important things. This includes wheel alignment and
tire pressure. It doesn't include which tires "grip" better or "feel" better
or....well, you get the drift. I'll admit that it doesn't hurt to listen to
what others have to say. There will be something of value there....for
instance: one set of Pirelli tires on my Miata had an unfortunate tendency
to wander on the water grooves on some of our Ca freeways. Go figure.

Tire technology has improved literally tenfold over the past so many years.
I remember my '70 TR6 came with (I believe) Firestone tires that lasted all
of 7,000 miles. Back in the '60s, if the urban legend is correct, GM was
paying their suppliers $2 per tire. Nowadays, I easily get around 40K on any
set of tires. I have "OEM replacement" tires on my Audi (for which I
probably paid too much) that are due for replacement at .....wait for
it....40K miles. I just replaced a set of el cheapos on our Chrysler Town
and Country (at around 40K) with yet another seat of el cheapos that will
easily do about the same.

Life is too short. Worry about other things. There is nothing here worth
getting all excited about.

Best,

Ken




> wrote in message
oups.com...
> Hi,
>
> I need advice about assessing tire quality from the experts/ gurus in
> this forum.
>
> With regards to tire composition and characteristics, what are the
> important things I need to look out for when assessing quality of an
> unbranded tire. Assuming that the tires are used in the recommended way
> ( such as not over loading or over speeding), I have heard that there
> are several characteristics of tires which make them last longer, and I
> am hoping you can shed some light on the following:
>
> Thread depth - Does the tire last longer if it has a deeper thread?
>
> Ply Rating - Is there any disadvantage to having a high ply rating,
> and is there any specific correlation between the number of plys and
> the weight. (for example each ply should add x kgs to the weight.)?
>
> Quality of rubber - Is there variation in quality of rubber that can
> make a tire last longer. Do they mix rubber with anything to increase
> durability?
>
> Tire patterns - what are the advantages and disadvantages of using a
> rib/lug/mix designs
>
> Weight of the tire - If it is a heavy tire would it last longer
> assuming that there is more rubber used.
>
> Sidewall - what is the difference between good quality and bad
> quality sidewall?
>
> The weather condition here is very hot, dry and sandy most of the year
> with 4 months of moderate rain. So even the well built roads tend to be
> very sandy which I assume increases tire friction. Some of the areas I
> travel through are very underdeveloped with a lot of pot holes on the
> roads. I have heard that nylon/x-ply/bias tires are better then radials
> for uneven road surfaces and radials are better for good road
> conditions, is this true?
>
> Thank you for your help,
> James
>

On Wed, 21 Sep 2005, KWS wrote:

> then you can gage your ignorance more accurately. With tires, I admit
> both ignorance and, to a great extent, a lack of understanding of the
> boundaries of tire technology.

Allow me to assist: No-name tires aren't near the *lower* boundaries of
tire technology, not the upper. This isn't suspect advertising hype, it's
just plain common sense.

> So far, the only feedback I have received were emotional responses (and
> some rants) with no understandable substance.

What part of "Unbranded tires are unbranded because the company who made
them does not wish their reputation to be harmed by being associated with
that particular tire, or because that particular tire was made in a
backalley shop in China that was told by an unscrupulous Western importer
'Make them black and round'" do you find difficult to understand?

> What I would like is more of an engineer-to-engineer response that deals
> with physical properties such as friction, stress loading, compounds,
> etc. The request remains open; I am always willing to be educated.

The internet is a little bit like God: It helps those who help themselves.
There are numerous very good educational pages on tire engineering
principles, even if you discard those put out by tire companies because
you consider their information tainted. Google is your friend.

> Buy on price. Go cheap. Why not?

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On Wed, 21 Sep 2005 12:23:34 -0400 "Daniel J. Stern"
> wrote:

> > then you can gage your ignorance more accurately. With tires, I
> > admit both ignorance and, to a great extent, a lack of
> > understanding of the boundaries of tire technology.
>
> Allow me to assist: No-name tires aren't near the *lower* boundaries
> of tire technology, not the upper. This isn't suspect advertising
> hype, it's just plain common sense.

Can you help us interpret what you say there? No name tires
arent "near" the lower boundaries... "not the upper".

I dont want to "read into" that contradictory statement.


--
remove MYSHOES to email

I have a feeling this is going to be a long thread with opinions all
over the map, mine included. And Daniel Stern may have it right - you
could be a troll motivated to generate a predictably long discussion for
whatever reason.

I am an engineer, but not with experience or technical competency in
tires - only what I have picked up as a consumer for 35+ years of
driving and DIY'ing who happens, for good or bad, to have an engineer's
brain (some might say that I had better give it back, or maybe even that
I'm due a refund).

Here are my opinions, probably none of which I can prove:
Use the UTQG standards (see
http://www.tirerack.com/tires/tirete....jsp?techid=48) ratings
that are by law printed on at least one side of every ti Treadwear,
Traction, Temperature.

Having worked in industry in engineering and management in competitive
situations, I've got to believe that there's a quite a bit of stretching
of the specs. by the manufacturers, and there's probably very little if
any meaningful enforcement for truth in specifications. Lacking any
other information to the contrary, I have to simplify things and assume
that they all cheat the same amount, so that would mean the specs. are a
good indicator for comparison shopping (and I asssume the tests to
determine the ratings are meaningful, which they probably are - wouldn't
be surprised if someone wants to argue with that, but that's a starting
point).

No reason these days to go anything less than 400 on treadwear rating.
There are some darn good affordable tires out there with 600 to 650 ratings.

Most tires (probably all I have seen) have an A traction rating - so
apparently that's very do-able even for a lower end tire (maybe the
spec. ranges are two broad).

Most temp. ratings are A or B. Don't go lower than B.

My personal philosophy: Elminate so-called "hi-performance" tires from
your search. Unless your *only* criteria for selection is road grip, you
will get very low bang for the buck - and road grip is not going to be
*that* much better regardless. "Hi-performance" tires, as a category,
have the following characeristics:
(1) Much more expensive unless you settle for even more compromises in
the design and quality than reasonable.
(2) They have poor tread life (way lower than a good, reasonably priced
touring tire).
(3) They have a tendency to have larger tread features (I forget what
you call the individual islands of rubber that make up the tread
pattern), which tend to cause funky wear patterns that become very noisy
starting near the middle of their short tread life.
(4) As a bonus to all the other issues, short of catastrophic failure or
your brother-in-law owning the tire store, you will never get a warranty
adjustment on a "hi-performance" tire even if you can document timely
alignments, maintenance, etc. - they don't care - the manufacturer
assumes that purchasers of "hi-performance" tires, by their very nature,
abuse their tires - burden of proof is on the consumer - and nothing is
provable - so forget it.

Also - buy your tires from the same place you get them installed,
balanced, and rotated and that does your alignments. And get printouts
of your alignments. The fewer parties that are involved, the less
finger pointing to avoid honoring a warranty claim if a problem should
occur (i.e., installer refers you to seller, seller refers you to
manufacturer, manufacturer refers you to the alignment shop, ad
infinitum - you get the picture.

When price shopping apples-to-apples, be sure to add up *all* costs and
benefits of buying mail order and local shop.

**Mail order:
Add in cost of shipping and paying a local shop for mounting and
balancing. Problems 10,000 miles down the road? No help from them.

**Local shop:
Mounting and initial balancing included in price - no shipping cost
added. Many/most shops give free balancing and rotation for the life of
the tires purchased there. Also see above
buying/installing/rotating/alignments all being single source (things go
a *lot* smoother if problems).

Can I assume you're not going to be driving well over 100 mph? Good.
Then stick with T or H rated tires (good for extended driving up to 118
mph). To go to higher speed ratings, other things are compromised as
evidenced that many tires are available in T/H speed rating with a given
treadwear rating or guarantee whereas the same tire (same exact model of
tire) in a V speed rating will have a significantly lower treadwear
rating or guarantee.

Most tread depths are 10 to 12 mm. If you have the treadwear rating -
it doesn't matter. Who cares what the intial depth is if it has
whatever treadwear rating. The only difference it could make is at
beginnng of tire life for resistnace to hydroplaning, but there are much
greater determinants of that in the other aspects of the tread design.

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
address with the letter 'x')

http://www.nhtsa.dot.gov/cars/testin...ireRatings.cfm is a
easy way to see the UTG Ratings for various tire brands. The UTG ratings are
required by the government.
http://www.tirerack.com/tires/SearchTires.jsp provides consumer opinons on
some tires, but in gerneral only brand name tires.
http://www.nhtsa.dot.gov/cars/rules/manufacture/ if you get the DOT code off
the tire, you can figure out who actually built the tire. For instance
Goodyear's Kelly Springfield subsiduary also market tires under the
MultiMile brand. Are they as good as Kelly Springfield tires? I don't know.
My Father always claimed they were better. Ironically he always claimed
Goodyear tires were sorry. Even more ironically he is riding around on
Country Squire Radials which are actually just Goodyear made tires. On the
other hand they have been far better than the Firestones that came on his
Ranger.

My opinion is that the different in cost between quality tires and crummy
tires is trival when spread over the life of the tires. Nothing can ruin a
car's driving characteristics faster than second rate tires. My first bad
experience with "bad" private label tires was a set of Grand Prix Radials I
bought for my Datsun 280Z. Turns out these were private labeled Firestone
Radial 500 tires. Yuck! That was the last time I bought private label tires
for my own vehicles.

Ed

C. E. White wrote:

> ...For instance
> Goodyear's Kelly Springfield subsiduary also market tires under the
> MultiMile brand. Are they as good as Kelly Springfield tires? I don't know.
> My Father always claimed they were better. Ironically he always claimed
> Goodyear tires were sorry. Even more ironically he is riding around on
> Country Squire Radials which are actually just Goodyear made tires. On the
> other hand they have been far better than the Firestones that came on his
> Ranger.

> ...Turns out these were private labeled Firestone
> Radial 500 tires. Yuck! That was the last time I bought private label tires
> for my own vehicles.

Good and bad designs can of course come out of the same factory. Specs.
are flexible, and, as with any commodity (tires, batteries, whatever),
compromises are made in the design to target a certain low end market
niche. I get tickled at people who use the fact that two products (one
a brand name, and one a no name) came out of the same factory, so - hey
- why not save a bunch of money and get the cheaper one that, by some
law of (meta)physics, *has* to be just as good.

Bill Putney
(To reply by e-mail, replace the last letter of the alphabet in my
address with the letter 'x')