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I think I'll give helium a shot. Maybe I can hover to work.
 
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...then buying a good tire gauge and routine monitoring of your tire pressures is just as effective IMHO.
I have found this to be necessary regardless if the tire is filled with nitrogen or standard air.

When I bought my car, the dealership put nitrogen in the tires and they put those stupid ugly green valve stem caps on. I told them to remove those eyesores and put on something that blends in. I knew that over time the tires are going to end up with standard air anyway, because I regularly monitor and adjust air due to the significant seasonal changes we experience in Minnesota. I don't have a tank of nitrogen sitting in my garage....
 
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Nitrogen makes a huge difference in my sport bikes. It doesn't leak out slightly slower, it leaks out at least 3x slower. The difference in "warm up" time is night and day. It's worth every cent I paid every time I paid it. That all having been said, IMO it's a complete waste in a street car unless you're getting it for free.
I've seen various numbers published about N2 vs. air leak rates in tires. CR tested 31 different models of A/S tires by filling one tire with air and it's mate with N2, both at 30 PSI. After one year, the average loss of the air-filled tires was 3.5 PSI and the average N2-filled tire loss was 2.2 PSI. Not a big difference over a year. Monitoring tire pressures with a good gauge on a routine basis and keeping the tires at the proper pressure is what's important, regardless of if you are using air or N2.
 

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Well, I monitored it before my ride every day for two years, only had to top it off once every three weeks vs. every week. Can't argue with the science, but most things aren't as cut and dry as they seem on paper. Your conditions (and results) may vary. I don't know if it makes a difference, but 30psi is only slightly better than a flat tire on a motorcycle.
 

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Well, I monitored it before my ride every day for two years, only had to top it off once every three weeks vs. every week. Can't argue with the science, but most things aren't as cut and dry as they seem on paper. Your conditions (and results) may vary. I don't know if it makes a difference, but 30psi is only slightly better than a flat tire on a motorcycle.
The diffusion of gases through a material are dependent on pressure, temperature, surface area, material composition and thickness among other variables.

The data was determined by actual testing, not empirical calculations on paper. My point all along is to monitor your tire pressures on a routine basis with a dependable gauge regardless of what you use to pressurize your tires.
 

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And your point is a good one. My point all along is that all testing is to some extent anecdotal, and just because something performs one way in one person's clinical test doesn't mean it will perform exactly the same in another person's real world application. With compressor air I've never made it through a winter without losing twice as much air with the bike on stands as your study averaged for the entire year.
There is a large group of amateur racers here because of the local Speedbowl, so almost everyone with a crotch rocket knows someone with a nitrogen bottle in their race trailer who will fill their tires cheap if not free. I don't know anyone who hasn't found pressure to remain stable at least twice as long as compressor air if not three times longer, including myself. Web surfers can cite me any study they want that says the grass in my town isn't green, but it won't change what my neighbors and I are looking right at while we're mowing it.
 

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No nitrogen narcosis for me. I'm loopy enough as is.???
 
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And your point is a good one. My point all along is that all testing is to some extent anecdotal, and just because something performs one way in one person's clinical test doesn't mean it will perform exactly the same in another person's real world application. With compressor air I've never made it through a winter without losing twice as much air with the bike on stands as your study averaged for the entire year.
There is a large group of amateur racers here because of the local Speedbowl, so almost everyone with a crotch rocket knows someone with a nitrogen bottle in their race trailer who will fill their tires cheap if not free. I don't know anyone who hasn't found pressure to remain stable at least twice as long as compressor air if not three times longer, including myself. Web surfers can cite me any study they want that says the grass in my town isn't green, but it won't change what my neighbors and I are looking right at while we're mowing it.
To a certain extent, you are comparing apples to oranges concerning motorcycle racing tires to passenger car tires but I hear what you're saying. The CR test showed a 40% slower leak rate using N2 vs. air in a group of passenger car tires which is comparable to your observations. I'm not really sure what you're arguing about.

Paying for N2 in passenger car tires isn't worth it, IMHO. If you can get it for free, then do so. Just check your tire pressures on a routine basis regardless.
 

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I'm not sure what the argument is either, through the haze of a few days of drunk posting on the subject all I can remember is taking some umbrage to the use of the word "slightly". And I seem to remember reading way back in the day that the surface area of the N molecule is 3X larger than N2O, so it logically followed to me that it would leak out 3x slower. Which didn't always prove out, but in my case, it generally did.
 

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I love how the thread didn't get past page 1 before it got derailed into a tire pressure discussion.

Not complaining, just amused.

Carry on....
 

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I'm not sure what the argument is either, through the haze of a few days of drunk posting on the subject all I can remember is taking some umbrage to the use of the word "slightly". And I seem to remember reading way back in the day that the surface area of the N molecule is 3X larger than N2O, so it logically followed to me that it would leak out 3x slower. Which didn't always prove out, but in my case, it generally did.
Going back to my Physical Chemistry days, while oxygen has a greater atomic mass than nitrogen, when nitrogen and oxygen are combined into their stable molecules, N2 and O2, the greater number of protons in the oxygen molecule draw the electron cloud closer to the nuclei than the nitrogen molecule does.

So the N2 molecule is indeed larger, but how much larger is it than an O2 molecule? As it turns out, a N2 molecule is about 300 picometers (1 picometer = 1 trillionth of a meter) while an O2 molecule is 292 picometers, or a difference of 2.6%. Not much difference, but certainly not 3X larger.

To be accurate, there's no such thing as molecular surface area that I'm aware of and N2O is laughing gas.
 

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I've seen N2 proponents claim that since N2 is lighter than air, you'll save un-sprung weight and have better performance. If you do the math for a typical set of tires (255/40/17) at 30 PSI, the reduction in weight by filling 4 tires with N2 instead of air is only 0.37 grams.

She blinded me with science! (Thomas Dolby reference)
 

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I'm just not a big nitrogen fan. It seems like the tire pressure is good for 3 months and then loses 4 to 5 lbs all at once. I just check my pressure every month with a good durable digital tire pressure gauge. Un less my wife say's " the red pitch fork is on my dash ".
 

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Going back to my Physical Chemistry days, while oxygen has a greater atomic mass than nitrogen, when nitrogen and oxygen are combined into their stable molecules, N2 and O2, the greater number of protons in the oxygen molecule draw the electron cloud closer to the nuclei than the nitrogen molecule does.

So the N2 molecule is indeed larger, but how much larger is it than an O2 molecule? As it turns out, a N2 molecule is about 300 picometers (1 picometer = 1 trillionth of a meter) while an O2 molecule is 292 picometers, or a difference of 2.6%. Not much difference, but certainly not 3X larger.

To be accurate, there's no such thing as molecular surface area that I'm aware of and N2O is laughing gas.
That may or may not all be true, but all that matters to me is how it plays out. If science proffessors say that what I've experienced is wrong, that's a shame but really doesn't change anything for my purposes. My empirical real world experience has pretty consistently delivered 3x slower leak rates over a period of years, so I'm really not losing any sleep over why it shouldn't be.
 

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That may or may not all be true, but all that matters to me is how it plays out. If science proffessors say that what I've experienced is wrong, that's a shame but really doesn't change anything for my purposes. My empirical real world experience has pretty consistently delivered 3x slower leak rates over a period of years, so I'm really not losing any sleep over why it shouldn't be.
Nor am I losing any sleep about it. My tires are filled with air, I check them regularly and they rarely require topping off.

Everything I stated in my last post is accurate. What is it that you think is not true?
 

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I'm not saying anything isn't true, I'm just saying that anyone who doesn't notice a huge difference in stability between air and nitrogen in a motorcycle tire is living in a different world than I am. I'd like to think that can be extrapolated up into more relevant areas, but it doesn't have to. I did it in one of my cars once and didn't think it was worth the cost, so probably not.
 

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On the topic of gas mileage...I'm now doing a whopping 15.9 after resetting my MPG dial 3 days ago.

I was doing 17.1 before that.

No sound nor sign of turbo issue...I think it is just a lot of stop and go traffic on city streets and my not so subtle throttle modulation.

For fun, I reset the mpg on the highway doing 60 (traffic was a little slow). I averaged 36 over 5 miles.
 

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2018 Q50 Red Sport 400 AWD
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On the topic of gas mileage...I'm now doing a whopping 15.9 after resetting my MPG dial 3 days ago.

I was doing 17.1 before that.

No sound nor sign of turbo issue...I think it is just a lot of stop and go traffic on city streets and my not so subtle throttle modulation.

For fun, I reset the mpg on the highway doing 60 (traffic was a little slow). I averaged 36 over 5 miles.
You have me beat...I can't even remember how to reset the MPG calculation.
 

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Scroll through the screens on your odometer then when u get to the MPG one, just hold the button you use to scroll right on your sterring wheel for around 3 second and the MPG should go blank.
And you can look back over your history via the InTouch lower screen. I reset my MPG every fill-up, which allows me to look back to determine if any trends are occurring.
 
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