**STUPID*** Question
Originally Posted by ru4real
I hope you don't believe him.
Air is approximately 78% Nitrogen. Nitrogen and any other gas will increase in pressure when heated, if volume is held relatively constant (like inside a tire). Have you heard of the ideal gas law?
Air is approximately 78% Nitrogen. Nitrogen and any other gas will increase in pressure when heated, if volume is held relatively constant (like inside a tire). Have you heard of the ideal gas law?
Originally Posted by ru4real
I hope you don't believe him.
Air is approximately 78% Nitrogen. Nitrogen and any other gas will increase in pressure when heated, if volume is held relatively constant (like inside a tire). Have you heard of the ideal gas law?
Air is approximately 78% Nitrogen. Nitrogen and any other gas will increase in pressure when heated, if volume is held relatively constant (like inside a tire). Have you heard of the ideal gas law?
To answer why use nitrogen in a tire; First and foremost, Pure Nitrogen has larger molecules than Oxygen and many of the other gases that comprise ambient air (though most of the others are only very small percentages). The result of this is less leakage from the tire (valve stems and seals), thus a more consistent pressure over the life of a tire or inflation interval, whichever way you look at it. Now, granted, if a tire is filled with regular air, only about 22% of that mixture would be more susceptible to said leakage. But, that's almost a quarter, and with a tire running 35 psi, that could amount to as much as a 9 psi loss, theoretically. The second reason is compressed Nitrogen is dryer than compressed air and this lack of moisture results in a more consistent pressure delta between a cold tire and a tire at operating temperature since it's expansion is uniform. Granted you could use an in-line air dryer for compressed air, but how many of those do you see at the Amoco station and that would require you to completely empty all your tires and refill them at the same time to get a consistent humidity between all 4 tires, and even then we're assuming the pump distributes this humidified air at an *equal* rate. Even better, one could argue that even with filling a new tire with Nitrogen there will be *some* ambient air remaining inside the tire from mounting it. We all know how humidity affects air, and the only real benefit here would be in a racing application where tire pressures are very critical. In formula one, pressures of 1/4 psi can have an affect on handling, so consistent and predictable expansion of a gas is beneficial. One could also argue this dryer gas inside a tire would lead to less oxidation and breakdown of the rubber compound inside a tire. In a racing tire that's not an issue, maybe a tractor tire or something with a longer life and greater surface area would better support that claim, but I've yet to see any conclusive research on the matter.
Bottom Line: Do You Need Nitrogen Filled Tires? NO
Will You Notice The Difference On a Street Car? NO
Will it help maintain pressure over a longer time? Yes
Is it worth $3-$5 a tire? Maybe, I say it's more snake oil and most places you can get compressed air for free.
Should I check my tire pressure regularly and top up my tires on days with low humidity? Yes
Do I use Nitrogen in my tires? NO
Was this post way too long for? Yes
Originally Posted by dude
Perhaps my brevity was misinterpreted. Although ambient air approaches 80% Nitrogen, I am not ignoring the combined gas/ideal gas law. Any gas will expand given a positive temperature Delta (Volume remaining constant).
To answer why use nitrogen in a tire; First and foremost, Pure Nitrogen has larger molecules than Oxygen and many of the other gases that comprise ambient air (though most of the others are only very small percentages). The result of this is less leakage from the tire (valve stems and seals), thus a more consistent pressure over the life of a tire or inflation interval, whichever way you look at it. Now, granted, if a tire is filled with regular air, only about 22% of that mixture would be more susceptible to said leakage. But, that's almost a quarter, and with a tire running 35 psi, that could amount to as much as a 9 psi loss, theoretically. The second reason is compressed Nitrogen is dryer than compressed air and this lack of moisture results in a more consistent pressure delta between a cold tire and a tire at operating temperature since it's expansion is uniform. Granted you could use an in-line air dryer for compressed air, but how many of those do you see at the Amoco station and that would require you to completely empty all your tires and refill them at the same time to get a consistent humidity between all 4 tires, and even then we're assuming the pump distributes this humidified air at an *equal* rate. Even better, one could argue that even with filling a new tire with Nitrogen there will be *some* ambient air remaining inside the tire from mounting it. We all know how humidity affects air, and the only real benefit here would be in a racing application where tire pressures are very critical. In formula one, pressures of 1/4 psi can have an affect on handling, so consistent and predictable expansion of a gas is beneficial. One could also argue this dryer gas inside a tire would lead to less oxidation and breakdown of the rubber compound inside a tire. In a racing tire that's not an issue, maybe a tractor tire or something with a longer life and greater surface area would better support that claim, but I've yet to see any conclusive research on the matter.
Bottom Line: Do You Need Nitrogen Filled Tires? NO
Will You Notice The Difference On a Street Car? NO
Will it help maintain pressure over a longer time? Yes
Is it worth $3-$5 a tire? Maybe, I say it's more snake oil and most places you can get compressed air for free.
Should I check my tire pressure regularly and top up my tires on days with low humidity? Yes
Do I use Nitrogen in my tires? NO
Was this post way too long for? Yes
To answer why use nitrogen in a tire; First and foremost, Pure Nitrogen has larger molecules than Oxygen and many of the other gases that comprise ambient air (though most of the others are only very small percentages). The result of this is less leakage from the tire (valve stems and seals), thus a more consistent pressure over the life of a tire or inflation interval, whichever way you look at it. Now, granted, if a tire is filled with regular air, only about 22% of that mixture would be more susceptible to said leakage. But, that's almost a quarter, and with a tire running 35 psi, that could amount to as much as a 9 psi loss, theoretically. The second reason is compressed Nitrogen is dryer than compressed air and this lack of moisture results in a more consistent pressure delta between a cold tire and a tire at operating temperature since it's expansion is uniform. Granted you could use an in-line air dryer for compressed air, but how many of those do you see at the Amoco station and that would require you to completely empty all your tires and refill them at the same time to get a consistent humidity between all 4 tires, and even then we're assuming the pump distributes this humidified air at an *equal* rate. Even better, one could argue that even with filling a new tire with Nitrogen there will be *some* ambient air remaining inside the tire from mounting it. We all know how humidity affects air, and the only real benefit here would be in a racing application where tire pressures are very critical. In formula one, pressures of 1/4 psi can have an affect on handling, so consistent and predictable expansion of a gas is beneficial. One could also argue this dryer gas inside a tire would lead to less oxidation and breakdown of the rubber compound inside a tire. In a racing tire that's not an issue, maybe a tractor tire or something with a longer life and greater surface area would better support that claim, but I've yet to see any conclusive research on the matter.
Bottom Line: Do You Need Nitrogen Filled Tires? NO
Will You Notice The Difference On a Street Car? NO
Will it help maintain pressure over a longer time? Yes
Is it worth $3-$5 a tire? Maybe, I say it's more snake oil and most places you can get compressed air for free.
Should I check my tire pressure regularly and top up my tires on days with low humidity? Yes
Do I use Nitrogen in my tires? NO
Was this post way too long for? Yes
