Checking Spare tire Air

[127.0.0.1]

Originally Posted by Yaris Hilton

Carrying a compressor is a good idea.

It's false that nitrogen is denser than air. It's a little less dense. Gases' densities are directly proportional to their molecular weights. Air (dry) is approximately 78% nitrogen, around 21% oxygen, with various trace gases making up the rest. Oxygen's molecular weight is about 32, nitrogen's 28, so air with its oxygen content is a little denser than nitrogen. I doubt you could measure a significant difference in the leakage rate. Nitrogen's a current "snake oil" fad for the most part.

nitrogen is not snake oil for the racetrack where tire temps hit extremes. but everywhere else, yes snake oil

[Yaris Hilton]

That's why I said "for the most part." It's long been used in jet aircraft tires that get really hot, too. And avoiding the water that builds up in tires with compressed air is a good thing.

[b_hickman11]

Originally Posted by MadMax

Unless of course you have a low or dead battery, at which point your sticky jack and underinflated spare will be the least of your worries!





Cheers! M2

My compressor doesn't use the car's battery. It has it's own power supply. You just have to charge it up once every 6 months, which is that big of a problem.

[yarrr]

Originally Posted by Yaris Hilton

It's false that nitrogen is denser than air. It's a little less dense. Gases' densities are directly proportional to their molecular weights. Air (dry) is approximately 78% nitrogen, around 21% oxygen, with various trace gases making up the rest. Oxygen's molecular weight is about 32, nitrogen's 28, so air with its oxygen content is a little denser than nitrogen. I doubt you could measure a significant difference in the leakage rate. Nitrogen's a current "snake oil" fad for the most part.

For the record, I run good ole regular air in my tires, but:

The idea behind nitrogen fills isn't about density, its about the size of the molecule, and a nitrogen molecule is bigger than an oxygen molecule. This supposedly helps individual molecules from seeping through the rubber.

[127.0.0.1]

best article about it

http://www.straightdope.com/columns/...instead-of-air

[yarrr]

Originally Posted by 127.0.0.1

2nd hit when you google nitrogen tire:

http://www.straightdope.com/columns/...instead-of-air

fixed!

[Yaris Hilton]

The oxygen molecule is about 3% smaller than the nitrogen molecule. Works in membrane diffusion oxygen concentrators, but I remain skeptical that you can measure a difference in leakdown rate in a tire. Snake oil.