Inflating Nitrogen into Tires



On Thu, 29 Nov 2007 20:23:01 -0800, Ted Bennett
<[email protected]> wrote:
>
>This just in: Rodney King was shot today.


Dear Ted,

Two or three times with birdshot--and then contined to bicycle home,
according to the report, an inspiration to us all, even if officers
described him as drunk and uncooperative.

Cheers,

Carl Fogel
 
>>>>> I don't know how the permeability of O2 compares with N2 through
>>>>> the rubber,


>>>> Yes, that's clear.


>>>>> but it can't be that much different.
>>>> O2 permeates 3-4 times faster than N2.


>> David L. Johnson writes:
>>> Carl the expert says otherwise (2.4), but both of you miss the point
>>> that 2 or 3 times faster than very, very slowly is still very
>>> slowly.


>> You could say that about most of the so called technical diatribes we
>> hear about wheel aerodynamics and rotating weight. My carbon wheels
>> are faster than yours and I ask where, how much, and with whom at the
>> pedals?


>> David L. Johnson writes:
>>> You will say Christ saith this and the apostles say this; but what
>>> canst thou say? -- George Fox.


>Jobst Brandt
>> Cautiously, "personally" and "actually" I canst say ********!


Ted Bennett wrote:
> Sounds like he just finished a couple big glasses of ale.
> This just in: Rodney King was shot today.


riding a bicycle, no less
--
Andrew Muzi
www.yellowjersey.org
Open every day since 1 April, 1971
 
SMS 斯蒂文• 夏 wrote:

> O2 permeates 3-4 times faster than N2.


This preferential leaking of O2 means that a tyre filled with
air, and then topped up periodically with more air will
gradually increase its N2 content until a new equilibrium is
reached in which the N2 content greater than atmospheric.

John
 
..Off-road, a valve cap can be darned useful on a Schrader valve.

It keeps twigs and brush from jamming the valve open and letting all
the air out of a motorcycle tire.

And here I was, thinking that the incident I was referring to required a rather improbable set of circumstances to become a reality! Compared to accidentally-jamming-open-with-a-twig my incidents seems about as far-fetched as gravity....
 
Carl Fogel writes:

>>>>>> "Personally?" For whom else do you speak otherwise?


>>>>> My evil imaginary twin, Skippy, of course.


>>>>>> The leakers are a bunch of pansies and don't recall the daily
>>>>>> tire pumping latex tubes in Clement Criterium required.


>>>>> And you no doubt sang the praises of them at the time...


>>>> Not at all. I was glad when I could get tubulars with brutal
>>>> tubes and later when we got Specialized Touring-II with present
>>>> day tubes.


>>> "Jobst Brandt & The Brutal Tubes: The Specialized Tour II" would
>>> be a good name for a bicycle rock band's reunion tour.


>>> But-yl prbly sA typo.


>> Well, personally I call them brutal tubes. What right do these
>> rubber chemists have to invent scinetifical sounding jargon like
>> butyl? I avoid "derbis" on roadsides to prevent punctures even
>> with brutal tubes.


>> I wonder how people speak when not doing so "personally".


> Personally, I was terribly pleased with myself on my ride this
> afternoon.


> At first I thought that some rancher had lost another hay bale and
> left straw all over the shoulder where I get onto the highway
> half-way up the ridge west of town.


> But after a minute or two, I realized that the snow had melted and
> made the road crew feel safe enough to come out and mow the dry
> grass and weeds, leaving a mess behind them.


> So I cheated even more than usual away from the edge of the road,
> hoping to avoid the nails, glass, wires, bits of old mufflers,
> torn-up cactus (never hit one yet!), and goatheads probably mixed in
> with the giant "grass" trimmings and other derbies.


> All went well uphill, so I turned around at the top and zoomed back
> down the other side into town with a fine tailwind, passing the
> parked mower two miles down the slope and still cheating more toward
> the center line than usual.


> Right after my ride, I was standing next to my bike in the garage,
> taking off my gloves and jersey, when the front tire abruptly began
> hissing loudly at me.


> I dug the tips of two goatheads out of it, but it still counts as
> only a single flat, my 49th of the year.


> Speaking impersonally, my opinion is that the Slime held while the
> tire was spinning, but the two pinholes ended up at the top of the
> tire when I parked the bike, the Slime drained away, and the barely
> sealed punctures gave way.


> But personally I think that the tube was just voicing its brutal
> opinion of me.


> Cheerssssss,


So what does the insertion of the word "personally" do other than show
a hesitance to utter an opinion, an opinion that can only be personal?
Jut say it without all the false modesty. Personally, it's tedious!

Jobst Brandt
 
On 30 Nov 2007 15:02:12 GMT, [email protected] wrote:

>Carl Fogel writes:
>
>>>>>>> "Personally?" For whom else do you speak otherwise?

>
>>>>>> My evil imaginary twin, Skippy, of course.

>
>>>>>>> The leakers are a bunch of pansies and don't recall the daily
>>>>>>> tire pumping latex tubes in Clement Criterium required.

>
>>>>>> And you no doubt sang the praises of them at the time...

>
>>>>> Not at all. I was glad when I could get tubulars with brutal
>>>>> tubes and later when we got Specialized Touring-II with present
>>>>> day tubes.

>
>>>> "Jobst Brandt & The Brutal Tubes: The Specialized Tour II" would
>>>> be a good name for a bicycle rock band's reunion tour.

>
>>>> But-yl prbly sA typo.

>
>>> Well, personally I call them brutal tubes. What right do these
>>> rubber chemists have to invent scinetifical sounding jargon like
>>> butyl? I avoid "derbis" on roadsides to prevent punctures even
>>> with brutal tubes.

>
>>> I wonder how people speak when not doing so "personally".

>
>> Personally, I was terribly pleased with myself on my ride this
>> afternoon.

>
>> At first I thought that some rancher had lost another hay bale and
>> left straw all over the shoulder where I get onto the highway
>> half-way up the ridge west of town.

>
>> But after a minute or two, I realized that the snow had melted and
>> made the road crew feel safe enough to come out and mow the dry
>> grass and weeds, leaving a mess behind them.

>
>> So I cheated even more than usual away from the edge of the road,
>> hoping to avoid the nails, glass, wires, bits of old mufflers,
>> torn-up cactus (never hit one yet!), and goatheads probably mixed in
>> with the giant "grass" trimmings and other derbies.

>
>> All went well uphill, so I turned around at the top and zoomed back
>> down the other side into town with a fine tailwind, passing the
>> parked mower two miles down the slope and still cheating more toward
>> the center line than usual.

>
>> Right after my ride, I was standing next to my bike in the garage,
>> taking off my gloves and jersey, when the front tire abruptly began
>> hissing loudly at me.

>
>> I dug the tips of two goatheads out of it, but it still counts as
>> only a single flat, my 49th of the year.

>
>> Speaking impersonally, my opinion is that the Slime held while the
>> tire was spinning, but the two pinholes ended up at the top of the
>> tire when I parked the bike, the Slime drained away, and the barely
>> sealed punctures gave way.

>
>> But personally I think that the tube was just voicing its brutal
>> opinion of me.

>
>> Cheerssssss,

>
>So what does the insertion of the word "personally" do other than show
>a hesitance to utter an opinion, an opinion that can only be personal?
>Jut say it without all the false modesty. Personally, it's tedious!
>
>Jobst Brandt


Dear Jobst,

Personally, I find your efforts to imitate an English teacher amusing.

But objectively they're just silly.

Cheers,

Carl Fogel
 
[email protected] wrote:

> Carl does say that it's silly to announce that you don't know what two
> rates are, but that they can't be very different when one is 2 to 3
> times greater than the other.


Welcome to Usenet. "Facts are facts and will not disappear on account of
your likes." Jawaharlal Nehru

The permeability is only one advantage in automobile tires, but it's
very real. Remember that a typical driver will likely _never_ check
their tire pressure during the life of their tires, which could be
several years.

The other advantage for automobile tires is that without the presence of
water vapor or oxygen the expansion due to heat will be less, and rust
will be inhibited.

I still probably wouldn't pay much, if anything, for nitrogen, but it's
just one advantage of buying tires at Costco. Costco uses nitrogen for
their own benefit in terms of warranty-related costs, they aren't
charging for the nitrogen.
 
On Fri, 30 Nov 2007 11:57:41 -0700, [email protected] may have
said:

>Dear Jobst,
>
>Personally, I find your efforts to imitate an English teacher amusing.
>
>But objectively they're just silly.
>
>Cheers,
>
>Carl Fogel


Both of you could stand to learn the art of the [snip]



--
My email address is antispammed; pull WEEDS if replying via e-mail.
Typoes are not a bug, they're a feature.
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"SMS 斯蒂文• 夏" <[email protected]> wrote in message
news:[email protected]...

> I still probably wouldn't pay much, if anything, for nitrogen, but it's
> just one advantage of buying tires at Costco. Costco uses nitrogen for
> their own benefit in terms of marketing, they aren't charging for the
> nitrogen.


Post corrected.

clive
 
On Fri, 30 Nov 2007 13:22:28 -0600, Werehatrack
<[email protected]> wrote:

[snip]

Dear Werehatrack,

There!

I do snip cautiously now and then. In fact, I'm doing it more often
these days.

But I learned long ago that there are an amazing number of
disagreeable posters who will denounce you at tedious and often
incoherent length for snipping their sacred prose and misrepresenting
them and twisting their words and lying and--

So I usually leave snipping to more daring souls, no matter who is
about to suffer my reply. Better to bore a little than to put up with
the extended nonsense about how-dare-you-snip.

(Besides, there's always the danger that a snip really will distort
things. It's always tempting to trim the obviously mistaken, poorly
written, error-filled blather of those who disagree with us on trivial
matters. Far better save the rest of RBT time and provide only our
concise, well-reasoned, fact-filled rebuttals to whatever the other
guy wrote . . . Wait a second, where did he say that? Oops, I must
have snipped it without even reading it.)

There are even a few posters who will delete their posts from Google's
archives, hoping that this will win an argument or protect their
reputation. The trick doesn't work if the post appears unsnipped in a
reply.

I should add that Jobst certainly doesn't delete his posts for those
reasons. He occasionally does delete a post, but it's just because he
notices a typo and wants to re-post the corrected version. That's why
we sometimes see what look like duplicate posts from him on servers
where the original post remains undeleted.

Cheers,

Carl Fogel
 
On Fri, 30 Nov 2007 11:21:27 -0800, SMS ???• ?
<[email protected]> may have said:

>The permeability is only one advantage in automobile tires, but it's
>very real.


You say that, and then go on to this:

>Remember that a typical driver will likely _never_ check
>their tire pressure during the life of their tires, which could be
>several years.


You fail to state who *will* check the pressure; clearly, the tires
will fail due to underinflation early if the pressure isn't checked in
that period, or else the issue of pressure loss isn't a real concern.
Since overwhelming common experience it that it *is* a concern,
somebody must be checking and inflating the tires. If your assertion
is correct (which I don't buy, but will allow for the sake of
discussion) then it's being done by someone transparently to the
customer. Since a lot of oil change service places also check tire
pressure, I suspect that this would be the primary source of inflation
maintenance for the owners that you describe. 100% N2 won't be used
for those pressure corrections. (Costco does not provide oil change
service at their local stores. According to the counter man at the
one nearest me, very few of their customers come back just for tire
pressure checks...and the tires they check often require some pressure
adjustment.)

>The other advantage for automobile tires is that without the presence of
>water vapor or oxygen the expansion due to heat will be less,


Okay, one last time: Oxygen and nitrogen have virtually identical
thermal expansion rates, and those rates are so small as to make no
difference at all. In any event, tire *UNDERINFLATION* is what
destroys tires, not minor levels of overinflation. Water vapor's
partial pressure in the mix is too low, even with a saturated
atmosphere at the compressor inlet* or with liquid present in the
tire, to have an important effect on the issue at safe operating
temperature ranges. Your assertion is still just as absurd as it has
been all along. (See below for a lengthier explanation of why water
vapor doesn't matter.)

>and rust
>will be inhibited.


Automotive wheels have their interiors painted, and rust from that end
isn't a problem. In nearly 40 years of dealing with car repair
issues, I have never seen an original equipment tubeless-tire wheel
that rusted from the inside out. It a steel wheel rusts, it's more
likely to be due to road salt or environmental salt spray, and it
starts at the outside edge (where the paint gets scraped off by a
variety of things) and works *in*; they simply do not rust from the
inside out. Ergo, rust from water (liquid or vapor) inside the tire
is not an issue.

>I still probably wouldn't pay much, if anything, for nitrogen, but it's
>just one advantage of buying tires at Costco. Costco uses nitrogen for
>their own benefit in terms of warranty-related costs, they aren't
>charging for the nitrogen.


You keep making this assertion of cause without a shred of real
evidence that this is really the case. Such evidence would be actual
figures showing that Costco had achieved a statistically significant
reduction in warranty expense as a result of the procedural change,
which given the relatively short time that they've been doing it, is
unlikely to be possible to prove. Even if someone at a Costco tire
center has made the assertion that what you state reflects the
*expectation* behind their policy, Costco's accountants almost
certainly wouldn't have been able to measure it in the time that has
elapsed. The reality is more likely to be that the policy was adopted
as a result of a decision taken solely on the basis of what someone
perceived to be its value in the marketing of their services.

If, over a period of several years, Costco can show a statistically
significant system-wide reduction in warranty expense which can be
directly attributed to N2 fills, then the claim can be verified.
Until then, its worth is unproven.



* In the absolute worst case real-world scenario, water vapor could
comprise no more than 4% of the air coming into a compressor. In most
instances, it's around 1%. It is interesting to note that the act of
compressing the air and then cooling it in the tank causes some of the
moisture to condense out. Ergo, unless the compressed air source is
from a compressor whose tank is so full of water that liquid is being
driven out of the supply valve, the air coming out of the compressor
will have less water vapor than the air that goes in, for any
environment where the water vapor is at a high enough level that it
might be able to condense inside the wheel to begin with. If the
water vapor partial pressure is below that level in the environment,
then the vapor is essentially completely irrelevant. But suppose that
the air coming from the compressor is at that real-world-impossible
4%-water-vapor point, and that for some unlikely reason none of it
condensed in the compressor's tank; the delivered vapor's *complete*
condensation later could therefore cause no more than a 4% drop in
pressure in a tire inflated with that mixture. 4% of 32psi is less
than 0.5psi. Most tire pressure guages are not accurate enough to
measure that difference.

Most tires are operated below their maximum rate pressure, and small
amounts of accidental overinflation generally will not even take them
to their rated pressure. For tires that are inflated cold to their
max rated pressure, however, operation beyond it as a result of
thermally-induced pressure change in a tire inflated with air, even
when moisture is present inside the tire, will not cause a problem;
the tire engineers have already taken this possibility into account.

The effects of water vapor on tire inflation pressure in service are
of absolutely no importance in automotive tires.



--
My email address is antispammed; pull WEEDS if replying via e-mail.
Typoes are not a bug, they're a feature.
Words processed in a facility that contains nuts.
 
SMS 斯蒂文• 夏 wrote:

> The other advantage for automobile tires is that without the presence of
> water vapor or oxygen the expansion due to heat will be less, and rust
> will be inhibited.


I like that one. No water vapor? Have you ever seen someone install a
tire? First thing they do is wipe around the bead with soapy water. It
makes the tire easier to get on, and improves the initial seal so they
can inflate it.

--

David L. Johnson

It is probable that television drama of high caliber and produced by
first-rate artists will materially raise the level of dramatic taste
in the nation.
-- David Sarnoff, 1939
 
[email protected] aka "Dear Carl" Fogel wrote:
> ...
> But I learned long ago that there are an amazing number of
> disagreeable posters who will denounce you at tedious and often
> incoherent length for snipping their sacred prose and misrepresenting
> them and twisting their words and lying and--...


Not that "Dear Carl" would ever misrepresent what someone writes and
accuse them of lying! [End Sarcasm]

--
Tom Sherman - Holstein-Friesland Bovinia
"Localized intense suction such as tornadoes is created when temperature
differences are high enough between meeting air masses, and can impart
excessive energy onto a cyclist." - Randy Schlitter
 
SMS 斯蒂文• 夏 said:
...Remember that a typical driver will likely _never_ check their tire pressure during the life of their tires, which could be
several years.

Really? Then I guess I don't know any typical drivers. All the people that I know well enough to have any insight into their driving habits will check tire pressures and fluid levels on a semi-regular basis, prior to longer drives, when filling up on washer liquid or something like that.
 
<MODE="htmlpedant">

On Fri, 30 Nov 2007 18:52:23 -0600, Tom Sherman
<[email protected]> may have said:

>[email protected] aka "Dear Carl" Fogel wrote:
>> ...
>> But I learned long ago that there are an amazing number of
>> disagreeable posters who will denounce you at tedious and often
>> incoherent length for snipping their sacred prose and misrepresenting
>> them and twisting their words and lying and--...

>
>Not that "Dear Carl" would ever misrepresent what someone writes and
>accuse them of lying! [End Sarcasm]


You forgot the opening tag, and the closing tag is improperly
bracketed. Ergo, the sarcasm attribute was not inherited by the text
block.

</MODE>



--
My email address is antispammed; pull WEEDS if replying via e-mail.
Typoes are not a bug, they're a feature.
Words processed in a facility that contains nuts.
 
<[email protected]> wrote: (snip) Better to bore a little than to put
up with
> the extended nonsense about how-dare-you-snip. (snip)

^^^^^^^^^^^^^^^^^^^
Dear Carl:
If you offend by snipping, it is generally only the OP. If you bore by
under-snipping, it is the whole readership; statistically, it is preferable
to snip tightly.

Besides, tight snipping directs the reader's attention directly to the
point--as I have done here.
 
"Werehatrack" wrote: (clip) (This opinion may change if they get a suit
from
> someone who didn't reinflate because he or she couldn't get access to
> N2 at the time it was needed...and had a tire failure with other
> complications as a result.)

^^^^^^^^^^^^^^^^^^
Do you suppose there are really people like that? Actually, virtually
everyone tops up with air, which is 80% nitrogen. Since the oxygen
selectively leaks away, and is replaced with 20% oxygen, the nitrogen
concentration keeps increasing in a tire that started with air. Similarly,
the nitrogen concentration keeps decreasing in a tire that started with 100%
nigrogen. So the two approach each other over time.
^^^^^^^^^^^^^^^^^^^^
(clip) I don't trust Costco's judgement any more than I trust any
> of their competitors; (clip)

^^^^^^^^^^^^^^^^^^^^
I believe Costco puts a high value on customer satisfaction, and they get
this by stocking quality products. However, their buyers are also human,
and they can be fooled by hype. This sometimes shows up when an interesting
new product appears on their shelves, and then is never restocked.
 
On Mon, 17 Dec 2007 20:31:53 GMT, "Leo Lichtman"
<[email protected]> wrote:

>
><[email protected]> wrote: (snip) Better to bore a little than to put
>up with
>> the extended nonsense about how-dare-you-snip. (snip)

>^^^^^^^^^^^^^^^^^^^
>Dear Carl:
>If you offend by snipping, it is generally only the OP. If you bore by
>under-snipping, it is the whole readership; statistically, it is preferable
>to snip tightly.
>
>Besides, tight snipping directs the reader's attention directly to the
>point--as I have done here.


Dear Leo,

How dare you snip my inspired minutiae!

In any case, I suspect that anyone who hasn't mastered the page down
key is too easily bored to be worth worrying about.

Not that this has turned into extended nonsense about snipping.

:)

Cheers,

Carl Fogel