Nitrogen instead of air

[akbeemer]

Huh ?? ? WTF Over?

I don't understand your point Paul. Yes, I identified the formula PV=nRT incorrectly. It is the ideal gas law not Boyle's law. However, H2O in a tire can change from a liquid state to a vapor and back depending on temperature and pressure. This change in state can result in pressure fluctuations that are larger than with "dry" nitrogen.

 

[vtbob]

I don't understand your point Paul. Yes, I identified the formula PV=nRT incorrectly. It is the ideal gas law not Boyle's law. However, H2O in a tire can change from a liquid state to a vapor and back depending on temperature and pressure. This change in state can result in pressure fluctuations that are larger than with "dry" nitrogen.

Yep in theory! Now assume a likely mass of water vapor in the tire...do the math ..temperature/state change. Just what is the pressure change in a normal tire volume. This only happens a 32F or colder.

Let us know the answer.

 

[omega man]

Huh ?? ? WTF Over?

Winter is here, oil considerations has been solved, tire considerations are good......on to gaseous and gas derivatives to put in the tires and the spare space in the top of the crankcase- maybe
OM

 

[JDOCKERY132445]

A good sales job

You guys will love this. Last week, I was in the yard when I heard the unmistakable sound of a flat tire flopping down the street. It was my neighbor in her Honda Hybrid. She was oblivious. I yelled and waved my arms until she finally stopped at the end of the street. She got out and asked what was wrong. Her right rear was flat. "How did that happen?" she asked.

I told her I had no idea how it happened and did not care; but that I would get my compressor out and inflate her tire so she could get it repaired.

As my compressor was building pressure, she asked if I had Nitrogen. I replied no, I only had beach air.

She then insisted that her tires only took Nitrogen because that was what the dealer installed.

I picked up my compressor and started walking back to my shop. Wait she said, what about my tire?

I said listen Sue, you have a choice. You can do this my way or your way. But you cannot tell me how to do it and I damned sure will not do it your way.

I filled the tire with good beach air and she drove all the way into town to get the repair and fill her tire with Nitrogen. It seems neither air nor Nitrogen cares what size nail is used in its release.

How do people get this stupid?

BTW,,,she is a retired high school science teacher.

 

[36654]

I don't understand your point Paul. Yes, I identified the formula PV=nRT incorrectly. It is the ideal gas law not Boyle's law. However, H2O in a tire can change from a liquid state to a vapor and back depending on temperature and pressure. This change in state can result in pressure fluctuations that are larger than with "dry" nitrogen.

Having never lived near the arctic regions, I must ask............do they use air compressors to inflate tires or bottled gas?

 

[omega man]

How do people get this stupid?

BTW,,,she is a retired high school science teacher.

Reminds of th time I was standing a large gable wall with the crane. By happenstance, one of the framers stapled the Tyvek on so when the wall was lifted into place- the print was upside down.
The homeowner arrived and flipped out proclaiming that the Tyvek would not work upside down
OM

 

[akbeemer]

Yep in theory! Now assume a likely mass of water vapor in the tire...do the math ..temperature/state change. Just what is the pressure change in a normal tire volume. This only happens a 32F or colder.

Let us know the answer.

Read post #16. From personal experience, in a car tire the change can be enough to set off a tire pressure warning and to make the tire look noticably under inflated. When the dealer put nitrogen in the tires the problem with the TPMS went away. Again, I think using nitrogen in a motorcycle tire is not worth the time or cost.

And the vaporization point of water is dependent on saturation level, pressure, temperature and to some degree whether or not the water is in a fixed volume or open space. Once water vaporizes it behaves as an ideal gas but in a tire that means there is more gas to deal with.

 

[akbeemer]

Having never lived near the arctic regions, I must ask............do they use air compressors to inflate tires or bottled gas?

I only recall seeing compressors that were in heated spaces during the winter. Not sure what they usde on trucks with onboard compressors. Never noticed.

 

[pauls1150]

Does Atlantic beach air have the same density as Pacific beach air?

And how often should I change the turn-signal fluid? both sides?

 

[MCMXCIVRS]

Not Helium - it's molecules are so small that exfilration would be a real problem. You want the non-flamable gas with the biggest molecules, ie highest atomic number. I have no idea what that is.

But helium would reduce un-sprung weight

 

[36654]

BTW,,,she is a retired high school science teacher.

I had a PhD in Acoustics lament that he couldn't find galvanized fasteners at the local hardware store. He had to settle for zinc-coated.......

 

[36654]

But helium would reduce un-sprung weight

Oh my God. That is actually true

Insignificant, but still true.

 

[Bud]

I had to get new tires on my car last week and they put nitrogen in them. The tire tech said the they lose less air because the molecules are four times the size of the oxygen molecules in air. Thus it does not seep out as well. He also said that the tire pressure would be more stable from cold to hot. Less pressure swing.
Everything that I read seems to indicate that it is the best thing since compressed air for tires. This made me think that nitrogen may work better in my motorcycle tires as well.
Does anyone have a thought or experience with nitrogen in motorcycle tires? Is there a downside to nitrogen in motorcycle tires?

Yes, because of the different density, Dyna Beads will not work in motorcycle tires filled with nitrogen.

 

[akbeemer]

Yes, because of the different density, Dyna Beads will not work in motorcycle tires filled with nitrogen.

And that's a bad thing?

 

[Gruesome]

At most ~1 psi loss due to water vapor pressure change


According to the graph above, if you fill your tires with moist (saturated with water vapor) air at +30C (~85F), and then cool down to -20C, you lose about 40mbar=0.04 atmospheres. Let's say you run your tires at 35 psi, which is about 2.5 bar (give or take), that makes about a 0.04/(2.5+1) ~ 1% change. I don't think you read your pressure meter to that precision (0.6psi).
If you filled at 50C, which is 122F (but it can't be a dry heat!), the most you could lose is 100 mbar=1.4 psi.

 

[bc1100s]

I had a PhD in Acoustics lament that he couldn't find galvanized fasteners at the local hardware store. He had to settle for zinc-coated.......

Nice.

 

[omega man]

BMW being a "luxury brand", doesn't it really deserve the best air in it's tires?

"Freshly packaged on Druidia, Perri-air promises the most luxurious ride your tires can produce". Outta the way Nitrogen, it's Perri-air or nothing.

OM

 

[36654]

According to the graph above, if you fill your tires with moist (saturated with water vapor) air at +30C (~85F), and then cool down to -20C, you lose about 40mbar=0.04 atmospheres. Let's say you run your tires at 35 psi, which is about 2.3 bar (give or take), that makes about a 2% change. I don't think you read your pressure meter to that precision (0.7psi).
If you filled at 50C, which is 122F (but it can't be a dry heat!), the most you could lose is 100 mbar=1.4 psi.

Gruesome,

Thanks for graph. At conditions where Nitrogen might be a factor, I'm certainly not getting out of the car or truck to worry about it, unless I have to.....

 

[rangerreece]

Gruesome,

Thanks for graph. At conditions where Nitrogen might be a factor, I'm certainly not getting out of the car or truck to worry about it, unless I have to.....
View attachment 53695

Damn Jon that's funny, now here I was thinking you didn't have a sense of humor.

 

[omega man]

Damn Jon that's funny, now here I was thinking you didn't have a sense of humor.

He's been opening prezzys early

OM