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Anyone running nitrogen in their tires? I hear of big reductions in wear due to cooler temps from one or two cagers but is this real world or just hype?
 

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K.I.A. '07 AW
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Hype... kind of
Most car tires are good for at least 30k miles, most of those are 50k+ miles. Motorcycle tires on the other hand have a much shorter life expectancy so nitro versus standard is Really a non issue. Now if you factor in that the "air" we breathe and inflate with is 78% nitrogen anyway and it really becomes an non issue.
 

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Less condensation as nitrogen is just a dryer air.
 

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Nitrogen is not a dryer air but it is a pure gas. Any moisture would deduct from the purity of the gas.

Not worth the cost or trouble.
Ok, I think we are splitting hairs Ken! It is a dry inert gas. I know how technical you can be.
 

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Nitrogen is not a dryer air but it is a pure gas. Any moisture would deduct from the purity of the gas.

Not worth the cost or trouble.
Sure it is.........Oxygen transports moisture, Nitrogen does not. "Air" has 20% oxygen and that's 1 in 5 of the the little molecules running around in your tire gluing your Dynabeds to the inside of your tire. It also expands, unlike nitrogen, and as you ride and your tire heats up, your tire pressure increases as the 02 expands. Doesn't happen with pure Nitrogen.

But if you are anal enough to worry about the difference, then you will be more aware/concerned enough to make sure that your TIRE PRESSURE IS AT THE PROPER LEVEL more often and THAT will extend your tire life and enhance your handling!

As for expense.....buy one of those portable air cans ($30), take it to a tire dealer that has a compressor that steals nitrogen from the atmosphere (watch out for Al Gore) and they'll fill you up for free.
 

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It [oxygen] also expands, unlike nitrogen...
I've seen this claim over and over again. Anyone that's had (and didn't sleep through) high school chemistry knows that is simply not true. ALL gases expand in proportion their temperature. In the case of a gas being contained in a more or less constant volume (a tire), a raise in temperature will result in a raise in pressure.
Ideal gas law is: pV=nRT
where
p is pressure
V is volume
n is the moles (amount) of gas
R is the gas constant
T is the temperature

While it may be possible that when used in tires pure nitrogen has slightly different properties than regular compressed air, it certainly expands as it heats up. Perhaps the lack of water in the pure nitrogen does help keep steel rims from rusting (or dynabeads from sticking). However, beyond that any claims made about the benefits of using Nitrogen may need to be taken with a grain of salt. Hey, it's your money.:deal:
 

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The reason nitrogen is more stable in a tire has more to do with the size of the nitrogen molecule compare to the size of an O2 molecule. Please read the following explanation from a person much smarter than I... :)

That flux of gas permeating through a material is directly proportional to the first three factors, below, and inversely to the fourth factor, below:
1. the area, call it A (in units of square centimeters, cm^2) of the sample of the rubber - More flux of gas would occur, if the area were larger, if everything else were the same; next,
2. the driving force for transport across the wall, which is the difference in concentration of gas (i) across the tire wall -for convenience with gases, a nearly exactly correct measure of this is the difference in partial pressures (pi) of that gas (i) on the two sides of the tire wall (i.e., pi inside minus pi outside) - Obviously, a higher partial pressure (pressure
units are cmHg, centimeters of mercury, and remember that 76 cmHg = 1 atmosphere = 14.7 psi) inside versus outside means there is more driving force to promote transport across the tire wall; then next,
3. the intrinsic permeability P, call it Pij, or P-sub-i-sub-j, is the "permeability coefficient" for the particular material (j) for that type of gas (i) - Note that various materials, i.e., different types of rubbers or plastics will permeate O2 faster or slower depending on the details of solid state structures of the materials, and different types of gases will permeate
each material faster or slower depending on the relative sizes of the gas molecules, as well as on how soluble the gas is in the solid material; then lastly,
4. the thickness L (in units of cm) of the material - you can see that if the tire wall were, say, twice as thick, one would expect half the permeation rate (flux, cm^3/s), all other things being equal.


In Barrers, for a typical rubber material, the permeability coefficient P, is dependant on temperature, but at 25C
(77F) for O2 is about 10 and for N2 is about 3.


I hope this helps clarify why O2 permeates faster through rubber than does N2 and a major aspect of why it is a good idea to significantly reduce the amount of O2 used to fill tires by replacing most of the O2 in air with enriched N2. Since N2 permeates through the tire rubber more slowly than would O2, using enriched nitrogen instead of air for tire filling contributes to better maintenance of the proper inflation pressure for the tire. Better pressure maintenance contributes
to reduced tire wear, so that tires last longer and tire replacement costs are reduced.


A simple but approximately correct explanation of this lies in the mechanics of the flexing of tire walls. If proper inflationpressure is maintained, the tire wall most effectively bears the weight of the vehicle. If pressure is allowed to fall too low, extra flexing that occurs as the vehicle bounces somewhat along the road causes excessive mechanical fatigue of
the structure of the tire. Similar to flexing a wire coat hanger, this fatigue can weaken the tire faster than would be thecase were it kept inflated to a pressure more consistent with that intended in its design.

Dr. Keith Murphy
Air Products and Chemicals, Inc.
Prism Membranes
 

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I was gonna say about the same as AZEagle. Nitrogen doesn't leak out. I put nitrogen in my truck times back in October and haven't had to "top off" yet. Don't have the VRod tires filled with N2, yet.

Really good idea for the wife's car though...
 

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My opinion a waste of time and money. Once you have waited and paid for the service of having your tires filled with nitrogen. the first time you need to add tire pressure what do you do go back and pay again or contaminate the nitrogen with air from a compressed air source.
 

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If you are a hard cornering, high speed biker it is absolutly worth, because of the better handling you can get and of course extend your tire's life.
I use nitrogen in my 2 cars (BMW X6 and 750) and in my 2 HD's (V-Rod and Road King) since maybe 5-6 years.
 

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Elephant Motors Rock
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The reason nitrogen is more stable in a tire has more to do with the size of the nitrogen molecule compare to the size of an O2 molecule. Please read the following explanation from a person much smarter than I... :)

That flux of gas permeating through a material is directly proportional to the first three factors, below, and inversely to the fourth factor, below:
1. the area, call it A (in units of square centimeters, cm^2) of the sample of the rubber - More flux of gas would occur, if the area were larger, if everything else were the same; next,
2. the driving force for transport across the wall, which is the difference in concentration of gas (i) across the tire wall -for convenience with gases, a nearly exactly correct measure of this is the difference in partial pressures (pi) of that gas (i) on the two sides of the tire wall (i.e., pi inside minus pi outside) - Obviously, a higher partial pressure (pressure
units are cmHg, centimeters of mercury, and remember that 76 cmHg = 1 atmosphere = 14.7 psi) inside versus outside means there is more driving force to promote transport across the tire wall; then next,
3. the intrinsic permeability P, call it Pij, or P-sub-i-sub-j, is the "permeability coefficient" for the particular material (j) for that type of gas (i) - Note that various materials, i.e., different types of rubbers or plastics will permeate O2 faster or slower depending on the details of solid state structures of the materials, and different types of gases will permeate
each material faster or slower depending on the relative sizes of the gas molecules, as well as on how soluble the gas is in the solid material; then lastly,
4. the thickness L (in units of cm) of the material - you can see that if the tire wall were, say, twice as thick, one would expect half the permeation rate (flux, cm^3/s), all other things being equal.


In Barrers, for a typical rubber material, the permeability coefficient P, is dependant on temperature, but at 25C
(77F) for O2 is about 10 and for N2 is about 3.


I hope this helps clarify why O2 permeates faster through rubber than does N2 and a major aspect of why it is a good idea to significantly reduce the amount of O2 used to fill tires by replacing most of the O2 in air with enriched N2. Since N2 permeates through the tire rubber more slowly than would O2, using enriched nitrogen instead of air for tire filling contributes to better maintenance of the proper inflation pressure for the tire. Better pressure maintenance contributes
to reduced tire wear, so that tires last longer and tire replacement costs are reduced.


A simple but approximately correct explanation of this lies in the mechanics of the flexing of tire walls. If proper inflationpressure is maintained, the tire wall most effectively bears the weight of the vehicle. If pressure is allowed to fall too low, extra flexing that occurs as the vehicle bounces somewhat along the road causes excessive mechanical fatigue of
the structure of the tire. Similar to flexing a wire coat hanger, this fatigue can weaken the tire faster than would be thecase were it kept inflated to a pressure more consistent with that intended in its design.

Dr. Keith Murphy
Air Products and Chemicals, Inc.
Prism Membranes
I used to work for Air Products :D I can tell you that the above is indeed true, but the differences in permeation rates are not as huge as it seems.

Think about this... If O2 did indeed migrate out of the tire preferentially to the N2 portion of air in the tire by a large factor, then after just a few "top offs" in a tire it would have a very high percentage of N2 as compared to O2, so you'd not have to worry any more, right? Well it doesn't quite work that way, but if you are a Nitrofill believer then just keep putting air in your tires and you can believe based on the above that your nitrogen concentration will just keep getting higher and higher over time without ever having to pay for it.

Nitrofill is really hype, and way overpriced for what you are getting. Besides those ugly green valve stem caps they put on don't match any car's color!
 

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Discussion Starter #14
My opinion a waste of time and money. Once you have waited and paid for the service of having your tires filled with nitrogen. the first time you need to add tire pressure what do you do go back and pay again or contaminate the nitrogen with air from a compressed air source.
Yeah that's part of the issue as well. The reason I posted in the first place was I saw a nitrogen generator for sale in a trade magazine and wondered about availability. If you need filling and all that is available is compressed air then it is way too much trouble for seemingly minor benefit.
 

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Partlino
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My brain hurts.....

The reason nitrogen is more stable in a tire has more to do with the size of the nitrogen molecule compare to the size of an O2 molecule. Please read the following explanation from a person much smarter than I... :)

That flux of gas permeating through a material is directly proportional to the first three factors, below, and inversely to the fourth factor, below:
1. the area, call it A (in units of square centimeters, cm^2) of the sample of the rubber - More flux of gas would occur, if the area were larger, if everything else were the same; next,
2. the driving force for transport across the wall, which is the difference in concentration of gas (i) across the tire wall -for convenience with gases, a nearly exactly correct measure of this is the difference in partial pressures (pi) of that gas (i) on the two sides of the tire wall (i.e., pi inside minus pi outside) - Obviously, a higher partial pressure (pressure
units are cmHg, centimeters of mercury, and remember that 76 cmHg = 1 atmosphere = 14.7 psi) inside versus outside means there is more driving force to promote transport across the tire wall; then next,
3. the intrinsic permeability P, call it Pij, or P-sub-i-sub-j, is the "permeability coefficient" for the particular material (j) for that type of gas (i) - Note that various materials, i.e., different types of rubbers or plastics will permeate O2 faster or slower depending on the details of solid state structures of the materials, and different types of gases will permeate
each material faster or slower depending on the relative sizes of the gas molecules, as well as on how soluble the gas is in the solid material; then lastly,
4. the thickness L (in units of cm) of the material - you can see that if the tire wall were, say, twice as thick, one would expect half the permeation rate (flux, cm^3/s), all other things being equal.


In Barrers, for a typical rubber material, the permeability coefficient P, is dependant on temperature, but at 25C
(77F) for O2 is about 10 and for N2 is about 3.


I hope this helps clarify why O2 permeates faster through rubber than does N2 and a major aspect of why it is a good idea to significantly reduce the amount of O2 used to fill tires by replacing most of the O2 in air with enriched N2. Since N2 permeates through the tire rubber more slowly than would O2, using enriched nitrogen instead of air for tire filling contributes to better maintenance of the proper inflation pressure for the tire. Better pressure maintenance contributes
to reduced tire wear, so that tires last longer and tire replacement costs are reduced.


A simple but approximately correct explanation of this lies in the mechanics of the flexing of tire walls. If proper inflationpressure is maintained, the tire wall most effectively bears the weight of the vehicle. If pressure is allowed to fall too low, extra flexing that occurs as the vehicle bounces somewhat along the road causes excessive mechanical fatigue of
the structure of the tire. Similar to flexing a wire coat hanger, this fatigue can weaken the tire faster than would be thecase were it kept inflated to a pressure more consistent with that intended in its design.

Dr. Keith Murphy
Air Products and Chemicals, Inc.
Prism Membranes
 

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Nitrogen DOES have a positive effect. Otherwise we wouldnt be so anal in using it in aviation. Thats not to say it has any real added value in motorcycles.
 

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Ok, I think we are splitting hairs Ken! It is a dry inert gas. I know how technical you can be.
Sorry. As a respiratory therapist that repairs oxygen equipment including cryogenics one of my peeves is nurses leaving notes that say "This tank leaks air". Air is a generalization and is made up of a mixture of total gases hat make up your room air. Nitrogen is an individual gas that makes up about 78 percent of air.
 

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Just like many new improvements over the years (and I do think it is an improvement, even if just a minor one).... it will eventually become the standard and the price will keep coming down until its free :D
 
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