deviltrick

Just had my tyres filled with nitrogen. Does it really make a difference? I haven't felt any changes, but I'll be checking mileage these days.

Any thoughts?

Jakarta Expat

If I remember correctly they did this experiment on Mythbusters on Discovery but for the life of me cannot remember the outcome on thier investigation.

SUNILP

IMO, it does not make any difference for everyday driving.

MMM430

Nitrogen has a more stable temp than Oxygen therefore there is less variance especially at higher speeds or in extreme climates therefore less variance in tire pressure. Oygen also holds moisture which Nitrogen does not so if you have crome rims this is a plus as moisture in your tires can lead to pitting in the crome.

So, for a few extra bucks you have more temp stable tires which can lead to improved tire life and mileage and save you from pitting your chromed rims!

platinumsc

This is all true but I don't like the ride with the nitrogen...especially on the highway. After thinking about it, here's my opinion of why. Oxygen expands with heat and friction. The expanding gases would act as a cushion which would soften the ride. Low profile tires need more cushion not less. With the nitrogen, there is no expansion. As a result, it probably explains why I feel like I'm riding on a really hard surface. I don't like it.

raymond g-

did you just make up that theory? that seems to counter basic physics....
though it's been a few years

platinumsc

You mean me? Fact: oxygen expands with heat. The rest I hypothesized off that fact. Sound logic.

raymond g-

granted, I didn't do as well as others in Physics 101. here was my line of thinking:

oxygen/moisture + heat = expand. expand = higher temperature = higher
pressure = less cushion.

conversely, nitrogen, being more stable under temperature and moisture variations
will hold the initial/charged pressure. thus, you can set pressure to comfort
mode and it will vary less.

truth be told, i slept during class.....

platinumsc

Okay, I see your point but I have 20 years of high performance tire experience...plus I did pretty well in science. Not that I remember half of the work but I was told my logical thinking was pretty good.
If you check the air pressure when the tire is cold, it will be less than if you check it after riding around. Heat and friction causes the molecules to expand. More air prssure, more cushion. That's comparing air to nitrogen.
Comparing air to air is different. More to your point. 40 lbs of air will feel harder than 32 lbs of air because the sidewall is stiffer.
Hopefully some science expert will chime in and set us both straight.

marco402

well, I'm not a scientist (and I don't play one on TV either ) but, having worked in aviation for a couple of decades, where ALL tire get only nitrogen, and tire speeds up to 225mph, both of you have a line on it...yes, the expansion of the gases due to heat will increase pressure, the 2 gases have about the same coef.of expansion, but the water vapor in 'air' expands more, therefore 'air' will expand (and inversely - contract) more then pure nitrogen. The cushion effect is just the difference between cold and warm pressures (2 or 3 psi nitrogen / 4-8psi air). its the pressure that softens or stiffens the ride, the nitrogen is just a more stable media, so you shouldn't need to tweak it as often...expanding gases in a fixed container (tire) won't give a softer ride, but will bulge the center tread and wear out the tire in the center, just has less pressure puts the onus on the sidewall/outer treads.. the trick is to get the happy middle-ground..
the moisture on the chrome wheel is a good point, though..

whoover

Nitrogen has three major benefits: 1) longer life of tires (because oxygen and ozone in air breaks down rubber) and wheels and valves (because of lack of water vapor); 2) slower pressure leakdown (smaller oxygen molecules escape rubber more quickly) and 3) longer tire life because they run cooler.

All three effects are small.