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[Zeros and ones]

Hey guys... just got my car services and was asked if I want nitrogen in tires. I have never done something like this before plus my service guy gave me a decent price for it.

So the situation.. the car is riding on KW v3's as they came out of the box. So no adjustments. The car has BMW Performance 313's on them. The set is fairly new... like just put them on in June.

So as for ride quality when I first got these new tires and rims... it was pretty good. Very nice and smooth but things were a bit bumpy. Much more than it was on my stock sport tires I had. Makes sense when you upgrade from 17" to 18". So I did check psi and everything was within spec and it was all good.

Got the car this past Thursday with nitrogen filled tires. So far I am impressed. The car feels like it is gliding.... bumps in the road are almost non-existent. The reflectors on the freeway are barely felt. It is as if someone pokes you just for a second. Road noise is down from where it was before. So far there is a lot of pluses.

But I am still skeptical about this plus still now convinced that it is worth the drain on the wallet because every time I have to fill the tire I have to put only nitrogen in the tire. If I put just regular air, I already kills the whole point of having nitrogen in the tire.

So I was wondering what you guys think? and if you guys have tried it before?

[Vigilante375]

You have to pay for Nitrogen to be put in the tires? I thought it was free but I never have looked into it. And I thought the main reason for it was it wouldn't degrade the tire as quick as air does......even though there is air on the outside of the tire.......if it isn't free then why pay for it when you can get something else that does the same damn thing for free, right?

[tracer bullet]

Eh.

Nitrogen is less likely to escape *through* the tire itself so it should keep a certain psi longer. It's also less likely to change pressure with changes in temperature.

Beyond that the nitrogen fills won't have any water vapor in them either as opposed to normal compressed air (unless that compressed air runs through a dryer first, some shops do this). So your wheels could last longer but who's had problems with wheels not lasting?

Worth it? Not to me. I'm an engineer, pretty anal retentive in general, and even I won't bother with this one.

[Section147]

Originally Posted by Zeros and ones

So I was wondering what you guys think? and if you guys have tried it before?

I had nitrogen in my GTI rubber a couple of cars ago. I noticed everything you did and thought it was totally worth the minor charge.
I never had to add anything to the tires as the psi stayed locked. There would not have been any charge if I had to, however.
The initial fee included all subsequent nitrogen additions...can't imagine someone charging you for that each time.

[Vigilante375]

Well its not worth it if you're a person who goes to the track regularly and have to lower/raise your PSI's. Until it's free, I'll stay away from it......

[Section147]

Originally Posted by Vigilante375

Until it's free, I'll stay away from it......

Point was that some places charge, some don't.

[Caduceus]

"It's also less likely to change pressure with changes in temperature."

Incorrect. Nitrogen is subject to the same laws of thermodynamics as all other gases. PV=nRT.

I personally use a custom gas mix in my tyres that contains 78% nitrogen and 21% oxygen.

[EINSER M]

i'm a fan courtesy of Savage BMW

[GaryS]

Originally Posted by Caduceus

I personally use a custom gas mix in my tyres that contains 78% nitrogen and 21% oxygen.

Hahaha

Originally Posted by Zeros and ones

The car feels like it is gliding.... bumps in the road are almost non-existent. The reflectors on the freeway are barely felt. It is as if someone pokes you just for a second. Road noise is down from where it was before. So far there is a lot of pluses....

So I was wondering what you guys think?

I think your tire pressure is lower now than it was before.

[Lester]

I use helium in my tires, and it makes the car feel lighter.

[bmw1racer]

Originally Posted by Caduceus

I personally use a custom gas mix in my tyres that contains 78% nitrogen and 21% oxygen.

LOL.

It's the 1% of "other gasses" that makes the difference.

[Dackelone]

Originally Posted by Section147

Point was that some places charge, some don't.

I guess I am lucky, my tire dealer only charges two euros per tire for Nitrogen gas in the tires. That's a no brainer to get! I always get Nitrogen gas filled in my tires always will.

[ken1137]

It would make sense if they could fill and guarantee there is 100% N fill, but this is not possible unless they go to the extent of removing the O2. Does anyone know if the dealer does this? We use N blankets for some processing and unless there is an escape route for the O2 it remains in place within an enclosed environment and the N fills the empty void.

[1speedbike]

Placebo effect is very strong.

[Red Bread]

Originally Posted by 1speedbike

Placebo effect is very strong.

Indeed, paying for it is even funnier. Reminds me of latex tubes in road bicycles, people pay silly money for a tube that doesn't hold air but is supposed to ride better.

[Zeros and ones]

Originally Posted by Caduceus

"It's also less likely to change pressure with changes in temperature."

Incorrect. Nitrogen is subject to the same laws of thermodynamics as all other gases. PV=nRT.

I personally use a custom gas mix in my tyres that contains 78% nitrogen and 21% oxygen.

hahaha.... I did too pretty sure I wouldn't pay for it again.

[Zeros and ones]

Originally Posted by 1speedbike

Placebo effect is very strong.

yes it is.... but i never said I was sold and I still am not. I am comparing both ride quality between my 1 series and my e39 5 series. My e39 has regular air and I make sure to keep on eye on the psi and the psi on my 1.

So far... my 1 rides much better than my 5. Before you ask on both cars the tires are brand new and the e39 is on 16" bbs rims with beefier tires.

Originally Posted by Red Bread

Indeed, paying for it is even funnier. Reminds me of latex tubes in road bicycles, people pay silly money for a tube that doesn't hold air but is supposed to ride better.

it may be silly but it is not like i have been always paying for it. Like I stated it was my first time and I was curious. Yes curiosity killed the cat but on the other hand if you don't ask you will remain stupid

[Red Bread]

Sorry, wasn't trying to say it's silly for asking, just funny that places have come up with a way to monetize airing up tires. Nitrogen makes sense for aircraft, where the water in plain air will freeze and cause balance issues, but it really doesn't offer any practical advantage for a daily driver, as it still fluctuates with temperature and purging the plain air is nearly impossible without two valve stems.

[Zeros and ones]

Originally Posted by Red Bread

Sorry, wasn't trying to say it's silly for asking, just funny that places have come up with a way to monetize airing up tires. Nitrogen makes sense for aircraft, where the water in plain air will freeze and cause balance issues, but it really doesn't offer any practical advantage for a daily driver, as it still fluctuates with temperature and purging the plain air is nearly impossible without two valve stems.

for sure +1. I tend to agree with that statement myself.

[JimD]

I am a mechanical engineer and I've read the claims for nitrogen. I would not pay anything for it but would let somebody put it in my tires if they wanted and didn't charge. I don't think it hurts anything but I do not think it helps either.

Compressing air tends to drive water out of air, not put water into air. That's why there is a drain valve on the compressor tank.

I think some places may use nitrogen just because they don't need a compressor to use it. The nitrogen comes compressed so you can just put a hose and valve on it and be in business. A compressor is noisy and requires a little maintenance.

Nitrogen is a gimmick. Not a problem but not worth money either.

Jim

[bmw1racer]

Originally Posted by JimD

I am a mechanical engineer and I've read the claims for nitrogen. I would not pay anything for it but would let somebody put it in my tires if they wanted and didn't charge. I don't think it hurts anything but I do not think it helps either.

Compressing air tends to drive water out of air, not put water into air. That's why there is a drain valve on the compressor tank.

I think some places may use nitrogen just because they don't need a compressor to use it. The nitrogen comes compressed so you can just put a hose and valve on it and be in business. A compressor is noisy and requires a little maintenance.

Nitrogen is a gimmick. Not a problem but not worth money either.

Jim

Electrical engineer here... Yeah, I think it's a gimmick as well.

[1speedbike]

Let's think about this logically...

First of all. As mentioned, regular air is 78% nitrogen, 20% oxygen, and <2% other gasses. Nitrogen and oxygen are of ALMOST identical mass. One mole (for non-chemists, it's a standard unit of measurement meaning 6.02 x 10^23 atoms) of oxygen (gas, o2) weights 32 grams, and one mole of nitrogen (gas) weighs 28 grams. One mole of each is 22.4 L worth of volume. There's much less than that in your tires. Even if you filled the tires with PURE oxygen vs PURE nitrogen, you'd save much less than 4 grams per tire (hell, probably less than 4 grams TOTAL).

Second of all, there is no other benefit that can even be argued for. All gasses obey charles' law, boyle's law, etc, and the previously mentioned combined gas law. No matter what the gas consists of, it always behaves the SAME way. PV = nRT. You raise T (the temperature), and given the same initial pressure (P) and the same number of atoms in the tire (n), the volume will ALWAYS raise by the same amount. R is the gas constant, always the same. You increase the pressure (P), say by hitting a bump in the road, and the tire will always react in the same way (though this isn't obvious from the law).

Third, about 1% of regular air is water vapor. The tires will always stay hot enough to not let the water freeze. Who cares if the water is there?

Fourth, do tires with nitrogen stay inflated longer? No. Some of the air actually diffuses THROUGH the tire. If anything, nitrogen, being a smaller molecule, would diffuse out of the tire more easily than oxygen. But this doesn't matter because air is mostly nitrogen anyway.

I did a quick google and found a list of a few "benefits" of nitrogen which are outright lies:


-Nitrogen filled tires remain at proper inflation up to four times (4x) longer
No. Just explained this.

-Helps improve fuel economy by reducing rolling resistance
No. Nothing about what is inside the tire has anything to do with rolling resistance. Since all gasses behave the same ways anyway, this still has absolutely no validity.

-Helps reduce tire tread wear caused by improper tire inflation
No. This is just a rehash of the first point they tried to make. The answer is still a firm no.

-Improves vehicle safety: 90 percent of tire blowouts are caused by under-inflated tires
Okay, really? This is yet another rehash of the first point.

-Nitrogen is the largest molecule in air so it doesn’t escape from your tires as easily as Oxygen or water vapor. Oxygen escapes up to four times faster and water vapor escapes up to 250 times faster, then Nitrogen alone.
No. More outright lies. How is N2 the LARGEST molecule in air? O2 is larger and weighs more. Water vapor (h2o) is slightly smaller, but exists in tiny quantities.

-The Nitrogen also minimizes the water vapor inside your tires so steel wheels are less likely to rust on the inside.
Maybe, but really no This is the only thing that may actually be true. Rusting is caused by oxidation, which happens in the presence of oxygen and is accelerated by water. However, most wheels are coated.. so.. you know... it doesn't rust the first time you drive in the rain.

All in all, nitrogen is a waste of money. Seriously.