Nitrogen Filled Tyres, any good?

[HDi fun]

I can't see it helping apart from for people who never check their tyres. But those who never check their tyres would:

a: never find a cut or other damage;
b: never see uneven wear due to bad geometry;
c: not care enough to even consider nitrogen inflation anyway;
d: generally abuse tyres by belting kerbs etc. thus causing a and b above.

I do like the idea of some of the sealants which claim to reduce sudden air loss in the event of a puncture. Though not a substitute for proper care and maintenance it does have a place. Apart from my one experience of it where I had immense difficulty balancing wheels/tyres after application.

 

[old-git]

The main problem with sealants, as far as I am concerned, is that they can hide a problem that may turn dangerous if not fixed properly. Better to simply have a usable spare, but I know many cars aren't fitted with one these days.

 

[SLEEPER]

As I understand it It is not that Nitrogen lasts for longer but that it changes less with temperature fluctuations. This certainly could make a difference because tyre pressures certainly do change with temperture . It also makes far more sense .

Pesonally I think its become a topic since the new GTR arrived with nitrogen as standard .
Its pretty much agreed on the GTR forum (which Im obviously on a fair bit) that whilst it might make a difference it was really a very clever marketing stratergy . - The car is so good its needs things others dont.

Bear in mind that the market isnt all car boffins so this probably sound extremely impressive to some potential buyers.

The proof that is has worked (the stratergy) is obvious. Threads like this for a start , plus a few places have even appeared offering to fill your car with nitrogen to make it into a race car. Plus I can just see the first chav to do it strutting around outside KFC saying how good it is.

As to if it works - Id look at it this way .Whilst it is unlikely to make a difference unless you are driving very seriously It certainly isnt detrimental so if you fancy trying it , its not a fortune so why not -

And before you ask........................... no I havent bothered either but I probably will try it .

 

[HDi fun]

The main problem with sealants, as far as I am concerned, is that they can hide a problem that may turn dangerous if not fixed properly. Better to simply have a usable spare, but I know many cars aren't fitted with one these days.

Yes, you have said this before and I do agree that it is a problem [especially] for the stereotypes I mentioned in my post. People who pay attention to tyres would generally be OK using sealants in the way they're intended to be used. It's not a substitute for inspection and maintenance. This is the reason that cars with run-flat OEM tyres must be fitted with a tyre pressure monitoring system.

I think we discussed something vaguely similar a few years ago. It's hard to know what to do for the best really. I have seen cars being driven with obvious and severe tyre under inflation problems of which the (brain-dead) driver is blissfully unaware.

The crux of the matter, Steve, is this: We can't fix clinical stupidity!!

That's another thread neatly hijacked... Sorry folks.

 

[SLEEPER]

Something else has come to mind....

Nitrogen, air or filling the tyres with helium ...none are a substitute for the correct tyre pressures . In fact if anyone is considering nitrogen it follows that the pressures must be set spot on . If not there is absolutely no point in using it.

 

[HDi fun]

Helium would present huge sealing difficulties. You'd be checking pressures every 5 minutes

 

[old-git]

As I understand it It is not that Nitrogen lasts for longer but that it changes less with temperature fluctuations. This certainly could make a difference because tyre pressures certainly do change with temperture . It also makes far more sense .

I would challenge anyone to be able to tell the difference between 78% and 95% nitrogen filled tyres. We are talking about the difference in temperature fluctuation of just 17% of the gas in the tyre.

The expansion ratio from boiling point to ambient is:

• nitrogen 1 to 696
• liquid oxygen 1 to 860

For sake of simplicity, we will assume a linear expansion ratio, so nitrogen expands 24% less than oxygen.

So, if the pressure in a tyre filled with air increases by 20% from 30 to 36psi (which would be a lot) when driven hard, by my iffy calculations I reckon that a tyre with 95% nitrogen (best possible scenario without serious evacuation of the tyre) 17% of the gas mixture in the tyre will expand 24% less. 17% of 6psi is 1.02psi. 24% less = 0.77psi. So the difference will be around 0.25psi. No one is going to be able to feel that.

This, of course, could be complete rubbish, so please correct me if it is.

 

[SLEEPER]

Sounds extremely impressive OG but Im not sure if you are on the right track

I did say possibly only wortwhile if you are driving serious and this is where nitrogen in tyres came from - the track.

From the top:

Air is 78 percent nitrogen, just under 21 percent oxygen, and the rest is water vapor, CO2 and small concentrations of noble gases such as neon and argon. We can ignore the other gases.

There are several reasons for using pure nitrogen in tires.

First is that nitrogen is less likely to migrate through tire rubber than is oxygen, This means that your tire pressures will remain more stable over the long term.
Second racers figured out pretty quickly that tires filled with nitrogen rather than air also exhibit less pressure change with temperature swings.
On the track this is both tyres heating up and changes in track temperature which are not neccessarily quite the same thing.

That means more consistent inflation pressures during a race as the tires heat up. And when you're tweaking a race car's handling with half-psi changes, that's important. (As I said this clearly isnt worthwhile unless you are "on the edge" )

So for most its just a very cute marketing stratergy like for example the new oils - on a normal road car they just dont make a difference

All replies to peterpedant@pmail.com

 

[old-git]

But I still come back to the fact that air is already 78%nitrogen, so the reduction in losses through the rubber is only improved by the additional 17% ish of nitrogen, this will not be noticable on a road car. On a race car, pressures are constantly being adjusted from race to race and from lap to lap so any reduction in losses will be masked by the constant checking and adjusting that takes place as a matter of course.

As an aside, where does the amateur race driver get his nitrogen, do tracks provide it?

If you are adjusting tyre pressures by as little as 1/2 psi then nitrogen may help but it still expands with temperature, so the tyre pressure will still vary just not so much.

Agreed, if you are on the edge then properly filled tyres (not done by Kwik Fit) may offer the slight edge over your opponent, unless he is also using nitrogen then you are doing it just to stay with him

 

[HDi fun]

If O2 bleeds away over time then we're left with a nitrogen enriched gas inside the tyre anyway Helium, hydrogen, CO2 etc make up very small parts of atmospheric air.

 

[old-git]

I rest my case m'lord

 

[SLEEPER]

But I agree and have repeatedly said so . On a road car I can't see it making a noticeable difference and that it may well be more marketing than actually useful.

All I am saying is that when you are searching for any advantage even very small differences are precious.

People have even been known to go to rediculous (in some people's eyes) ends to save weight for example. This is similar.

As to the fifth gear vid - There will surely be one extolling the virtues of nitrogen on the interwebby .

 

[HDi fun]

This is like audiophilia. Diminishing returns. Generally applies.

I listen to music through a couple of thousand £££'s worth of hifi gear. And it's good. Very good.
Twenty grands worth ought to be superior. But ten times better. Possibly not.

 

[old-git]

People have even been known to go to rediculous (in some people's eyes) ends to save weight for example. This is similar.

As to the fifth gear vid - There will surely be one extolling the virtues of nitrogen on the interwebby .

Removing weight is a proven performance enhancer

Nitrogen does have some minor advantages, but only if you remove ALL of the air in order to achieve any improvement.

Dry air would work just as well (the water vapour is the main reason for pressure increases caused by heat), apart from the minor increase in long term pressure loss and the dubious improvement in pressure stabilisation. F1 teams use nitrogen because they already have it on tap as they use it for their pneumatic tools.

 

[SLEEPER]

This is like audiophilia. Diminishing returns. Generally applies.

I listen to music through a couple of thousand £££'s worth of hifi gear. And it's good. Very good.
Twenty grands worth ought to be superior. But ten times better. Possibly not.

Maybe we should strat a hi fi thread - could be entertaining. (as thats my other obssession )

You are right of course £2k can give you a super sound -You can spend any amount but money itself wont neccessarily improve anything I thinks its more about macthing the system which will only be as good as its weakest link. Trouble is that can start to be the CD /vynal itself which is very frustrating

 

[HDi fun]

Time for an off-topic in the General Room..... Over to you mate