nitrogen tire fill plus air?

[XS650]

Originally Posted By: edhackett
I am in fact, right now, breaking apart Ar gas and reacting it with oxygen to form ArO. Inert is surely a relative term.

Ed

Wowser, I have trouble just drinking coffee and typing at the same time.

 

[Shannow]

Originally Posted By: unDummy
How do you increase the age of tires? cook in oven with reduced nitrogen and increase oxygen level?
http://tirenitrogen.typepad.com/techinfo/Ford%20Baldwin%20TireAging%20%232.pdf

With the movement toward 50k-100k+ long life greenie-eco-mpg tires, I would think that those consumers would definitely benefit from reduced tire aging when using nitrogen over air, especially since we can't get tire expiration dates legislated and enforced.


Going to be a little hard to keep the engine running in a nitrogen filled capsule, let alone get power to the wheels.

 

[Kestas]

Originally Posted By: unDummy
I'm just not finding the anti-nitrogen in tires studies or papers.

It's rare to have a study funded only to conclude there is nothing to show and the status quo is okay. Who would fund such a study? Consumer Reports? Well, they did such a study and the data shows me there is little significant improvement with nitrogen-rich tires. Certainly not enough to warrant the trouble or expense of using nitrogen.

Tire makers are pretty much in bed with the nitrogen producers. They tout whatever they can to help their dealer buddies make more money.

You won't find anti-nitrogen papers because there are miniscule positive effects with using nitrogen in tires (slightly drier air, less oxygen for the metal and rubber, fire suppression), which cannot be ignored. But again, the effects are so small that nitrogen is not worth the trouble or expense. A person's efforts are better directed to other more worthy issues with the vehicle.

 

[Sayjac]

Quote:
Even the Consumer Reports test was a little too inconclusive for me.
The difference of inconclusive is one is free, one costs money. Also imo, there's too much room for installer shananigans in the emptying and filling, (or not filling) with N2. I've lived a long time using the 78% stuff and checking my tire pressure occasionally, without issue. Discount Tire doesn't use/offer it, though recently they have gone to metal covered valves. Still think N2 is a sweet scam for those in the biz.

That said, to each their own. If paying for and using N2 makes one feel better about not needing to check air pressure, go for it.

 

[Shannow]

Also, with tyres (well bike tyres at least), using them as tyres (working the rubber) reduces leakage significantly over just having them sit.

I would imagine a tyre sitting in a shed would leak far more than a tyre in actual use, amplifying the apparent effect of any benefits that may exist.

 

[edhackett]

XS650, it's amazing what you can do with 2000 watts of highly focused RF.

As Shannow points out, less O2 in the tire may be all well and good, but how do you prevent damage from O2, ozone, and UV on the outside?

Also if new tires are mounted using water/soap or water/mounting lube, there goes any benefit to the dryness.

Ed

 

[unDummy]

Tires are pressurized. As such, not worried about outside air.
I think one of the previous links mentioned that.

UV? no-one uses tire shiny ghetto protectant? bling bling keeps the UV away.

 

[edhackett]

I've see a lot of tires that are weather checked and hard as a rock on the outside and still look like new inside when removed from the rim.

Ed

 

[Shannow]

Originally Posted By: unDummy
Tires are pressurized. As such, not worried about outside air.
I think one of the previous links mentioned that.

UV? no-one uses tire shiny ghetto protectant? bling bling keeps the UV away.


Law of difusion says that oxygen will permeate INTO a nitrogen filled porous membrane...if the oxygen leaking out is why air is bad, then leaking in WILL occur.

 

[Carbon]

Originally Posted By: Shannow

Law of difusion says that oxygen will permeate INTO a nitrogen filled porous membrane...if the oxygen leaking out is why air is bad, then leaking in WILL occur.

Are you sure you are not thinking of some law regarding liquids and salts that do ionic bonding?

 

[Shannow]

Yeah, took me a while to accept it...

But oil leaks (weeps) on high voltage transformers mean oxygen attack on insulation materials.

It didn't make sense, until I saw some stuff on oxygen ingress into wine bottles, even when they are capped and pressurised with CO2...

Consider a tyre filled with pure N2, the partial pressure of O2 is nothing, absolute zero essentially, while outside is 3psi give or take...oxygen is going to want to leak in., and nitrogen leak out.

 

[Shannow]

If this works

http://www.onsitegas.com/faq/what_membrane.asp

Then so does the reverse.

edit...if O2 in leakage was part of the reason for apparently lower pressure decays (N2 leaking out, O2 leaking in), then I'd be so much in favour of N2 fills it's not funny.

Quick, someone get CR to check for O2 in their stored tyres and report back.

 

[CapriRacer]

Originally Posted By: Carbon
Originally Posted By: Shannow

Law of difusion says that oxygen will permeate INTO a nitrogen filled porous membrane...if the oxygen leaking out is why air is bad, then leaking in WILL occur.

Are you sure you are not thinking of some law regarding liquids and salts that do ionic bonding?


It's called Dalton's Law. I talk about it here:

http://www.barrystiretech.com/nitrogeninflation.html

Originally Posted By: unDummy
I'm just not finding the anti-nitrogen in tires studies or papers.


My web page has several "anti" nitrogen studies - "anti" meaning no benefit. I'll bet it's kind of hard to get people's attention when the conclusion is "No Difference!"

Originally Posted By: Kestas
.....Tire makers are pretty much in bed with the nitrogen producers. They tout whatever they can to help their dealer buddies make more money.......


Yet, oddly enough, tire manufacturers do not say there is a benefit. Their positions are suspiciously nutral!

 

[edhackett]

Yes, the concept of a gas diffusing across a pressure gradient is hard to grasp.

One of our instruments is extremely sensitive to oxygen contamination. The core of the instrument is quartz tubing sealed with Teflon ferrules. The carrier gas is helium. We constantly have to monitor the system for leaks with a helium detector. Even if the helium is actively leaking out under 3.5 psi pressure, oxygen is "leaking" in.

Ed

 

[Carbon]

OK on the Dalton's law. Regarding what tire manufactures say, I don't know what they say one way or the other on N2, nor do I know their positions on tire dressings or other such topics.

In your excellent write-up you say
Quote:
While that was a difference of 1.3 psi in favor of nitrogen (37%), that is not a lot of pressure difference - and more importantly, there was loss for both gases.

In other words, even with nitrogen you still have to check your tire's pressure.
If you can accept that there may be a 37% less pressure loss over a period of time, doesn't that constitute a real advantage? It seems real (significant) to me. We can agree that an extra fee to have N2 installed is a real disadvantage.

Here is a math problem. Assume a person who has the air topped off to 1 PSI over the car nameplate recommendation of 30 PSI at the annual oil change each October. Assume the driver drives 10000 miles each year. Assume the N2 filled tires lose 2.2 PSI in a straight line vs 3.5 PSI for air (CU study). Assume straight line MPG of 30.7 MPG at 33 PSI and 30.2 MPG at 27 PSI (eyeball roughly from http://www.energy.ca.gov/reports/2003-01-31_600-03-001CRVOL2.PDF fig 3). Neglect tire wear or deterioration. Neglect value of time to gas up. Assume $4 per US gallon of fuel. What is the fuel savings annually using N2 vs air?

Fair problem setup?

 

[Shannow]

How about the other way, where the N2 guy assumes his tyres are "filled for life" due to the advertising blurb, and loses 2.2psi p.a. versus the guy who knows that tyres need checking, and tops up 4-6 times per year on free air at the station, running an average of much less than a psi down all year versus Nitrogen's more than 1psi down on average.

One of them is more likely to pick up a slow leak too.

 

[SteveSRT8]

As Capriracer noted NO major tire manufacturer specifically recommends Nitrogen fill.

Ed Hacket really pointed out a good one... what if tire installers are slapping soapy water all over the bead?

Too many 'what ifs' and no real supportive data.

Carbon has an agenda: to support Nitrogen fill.

 

[Carbon]

Originally Posted By: SteveSRT8
As Capriracer noted NO major tire manufacturer specifically recommends Nitrogen fill.

Ed Hacket really pointed out a good one... what if tire installers are slapping soapy water all over the bead?

Too many 'what ifs' and no real supportive data.

Carbon has an agenda: to support Nitrogen fill.

1. CapriRacer did not say any tire makers say N2 in passenger tires is a bad idea.

2. Water induced during install is reasonable question.

3. Too many what ifs? What does that mean? If you are going to do a simple math problem, you have to make assumptions. If you have a better way to state a simple economic approximation calculation, state it. Or maybe you think trying to apply math to a topic that you "know the right answer to" is out-of-line. If the premises of the problem I stated are too complex, what changes would you make? Or do you consider such discussions to be heretical? I don't see the value of use of N2 in passenger car tires to be the same for everybody.

A more complex problem would be to assume filling with N2 at tire installation time, and topping off annually with air over the 4-year life of the tires.

4. Addenda? I already said I don't use N2. I don't recommend that you use N2. My addenda is people making blanket statements and dogmatically attacking others. CapriRacer is an example of a rational analyst who is not on the attack. I think that his usage of "real" could use some revision.

Shannow, yes. The guy who fills his tires with air 4..6 times per year with free air is going to be economically ahead of the guy who only gets his air topped up at oil-change time and relies on TPMS to handle that slow leak detection. Free air is not as available as it used to be. That more attentive person is going to even be able to adjust for seasonal temperatures too. There are many people who are not as attentive to tire care as you presumably are. If somebody were to pay someone else to top off his/her air, what would you value that at?

 

[Shannow]

Originally Posted By: Carbon
1. CapriRacer did not say any tire makers say N2 in passenger tires is a bad idea.


He said that no OEMs recommend it...to use that as a counter argument, when tyres have been filled with mostly nitrogen since Dunlop invented them is silly.

Originally Posted By: Carbon
Shannow, yes. The guy who fills his tires with air 4..6 times per year with free air is going to be economically ahead of the guy who only gets his air topped up at oil-change time and relies on TPMS to handle that slow leak detection. Free air is not as available as it used to be. That more attentive person is going to even be able to adjust for seasonal temperatures too. There are many people who are not as attentive to tire care as you presumably are. If somebody were to pay someone else to top off his/her air, what would you value that at?


About the same, and probably cheaper than the Nitrogen guy, who should have his tyre pressures checked/adjusted at about the same intervals as well.

They aren't "fill for life", as you so quite rightly have pointed out.

 

[Carbon]

Originally Posted By: Carbon
Here is a math problem. Assume a person who has the air topped off to 1 PSI over the car nameplate recommendation of 30 PSI at the annual oil change each October. Assume the driver drives 10000 miles each year. Assume the N2 filled tires lose 2.2 PSI in a straight line vs 3.5 PSI for air (CU study). Assume straight line MPG of 30.7 MPG at 33 PSI and 30.2 MPG at 27 PSI (eyeball roughly from http://www.energy.ca.gov/reports/2003-01-31_600-03-001CRVOL2.PDF fig 3). Neglect tire wear or deterioration. Neglect value of time to gas up. Assume $4 per US gallon of fuel. What is the fuel savings annually using N2 vs air?

Fair problem setup?


Not seeing any comments on the problem setup, here is my calculated number for that description: $10.79
I may or may not have calculated correctly.