Inflating tyres with nitrogen

Where do you get your tyres filled with nitrogen? Is there anyone who has bought nitrogen bottles to top up tyres and if so where do you get them from

Some Porsche centres and many tyre outlets now have N2 equipment. You can purchase nitrogen from a gas welding supplier, but will need to pay a year's rental on the bottle in advance, also purchase pressure valves, hoses and tyre gauges, which will be expensive. In fact, You won't need much topping up as N2 holds it's pressure over a prolonged period, so periodically returning to where you got the gas in the first place is your best bet and you can still top with air if you're stuck. It won't do any harm. Regards, Clive.

PC Exeter [ ]

Local ATS branch - £1.25 per tyre.

Costco as well.

When the tyre is put on the rim some air will be entrapped it is inevitable. Oxygen molecules are apparrently smaller that the molecular stucture of the vulcnaised carcass an can thus bleed out and probably it is the oxygen component of the air that has leaked so you can either repessurise with pump air at the garage & repeat as necessary or top up again with more nitrogen and with a bit of luck you will have "bled" all the air out and this time you should suffer a much less significant pressure drop. If you get repeated pressure losses of the same order of amgnitude have the wheel checked for leaks because the nitrogem molecules are to big to slip through, in much the same way the newest iteration of A/C gas can bleed away throught the older types of A/C pipe.

Air is composed of approx 78% Nitrogen so is there any point trying to fill the other 22%? Do the places that do the nitrogen filling evacuate the air that is in the tyre prior to filling with nitrogen? To me it is a marketing con based on what they do in F1. Cheers,

Speaking personally, yes and yes. BTW: F1 haven't used nitrogen in their tyres for many years. Regards, Clive.

Not sure that's correct now Clive. Formula One tyres are normally filled with a special, nitrogen-rich air mixture ? Whether or not this is 100 percent nitrogen I'm unsure. Personally I cannot see its worth the trouble unless you're tracking the car.

Hi Andy, F1 regulations require tyres to be inflated either with air or nitrogen, but in practice, Pirelli use dry air stored in bottles. No need to track a car for nitrogen to be advantageous. I haven't needed to top up my tyre pressures for 3 years! [ ] Regards, Clive.

With air in the tyres, I see around 10 psi increase in tyre pressures when running quickly on road or in even warm weather. With nitrogen fill the pressures are constant on road and on track. The question therefore is whether higher than normal pressures when running is good/bad/beneficial for grip, wear and tyre life?

Clive [8|] Think I stand corrected[ ] Regards Andy

I am pleased to see that at Goodwood tomorrow the air will be dry, earlier this year the tunnel was full of wet stuff.

I suppose that depends on what the manufacturer did the initial setup with. If porsche used air they might have factored in a specific psi for a tyre knowing the pressure will increase during use. Filling with nitrogen removes the increase so the tyre could end up being under inflated, or am i reading to much into this?

I've been trying to remember my Physics/Chemistry A-Level, but I'm pretty sure that all gasses will change pressure by the same amount when heated. I think the variation in pressure between Nitrogen filled tyres and those filled with air is probably only due to the moisture content of the gas in the tyre, which will have an effect on the overall pressure in the tyre as temperature changes (hence the comment that the F1 may use dry air rather than Nitrogen). Having read a little bit about it and it seems that advantages of Nitrogen are: 1) The larger gas molecule means that gas escapes the tyre more slowly and therefore your tyres will stay inflated for longer (not a problem if you check your tyre pressure regularly). 2) Reduced corrosion due to reduced moisture and, I guess, reduced oxidation due to absence of oxygen. I'm not convinced that this is terribly reliant to alloy wheels. 3) Reduced variation in pressure due to moisture, this will be very dependent upon the level of moisture in the air when you pump up your tyres. Personally I think it's a money spinner that the tyre companies use to increase your tyre bill, it's probably just as cheap for them to keep a Nitrogen bottle than pay for the maintenance of a pump. I'm not sure I could ever tell the difference, but that's my opinion, I could be wrong.

At £1.25 per tyre it's hardly a money spinner. The OP wanted to know where he could get it and we have endeavoured to tell him. Most of us using it are convinced it's better, but its use is not mandatory. Don't use it if you're convinced a.) it's a rip off or b.) it's all a load of nonsense or c.) You don't use your car in such a way for it to make any difference. [ ] Regards, Clive.

I think the variation in pressure between Nitrogen filled tyres and those filled with air is probably only due to the moisture content of the gas in the tyre, which will have an effect on the overall pressure in the tyre as temperature changes (hence the comment that the F1 may use dry air rather than Nitrogen). Having read a little bit about it and it seems that advantages of Nitrogen are: 1) The larger gas molecule means that gas escapes the tyre more slowly and therefore your tyres will stay inflated for longer (not a problem if you check your tyre pressure regularly). 2) Reduced corrosion due to reduced moisture and, I guess, reduced oxidation due to absence of oxygen. I'm not convinced that this is terribly reliant to alloy wheels. 3) Reduced variation in pressure due to moisture, this will be very dependent upon the level of moisture in the air when you pump up your tyres. Personally I think it's a money spinner that the tyre companies use to increase your tyre bill, it's probably just as cheap for them to keep a Nitrogen bottle than pay for the maintenance of a pump. I'm not sure I could ever tell the difference, but that's my opinion, I could be wrong. These are some of the reasons I want to carry on having my tyres filled with nitrogen, I will be taking the turbo on track also & it will be beneficial for me to use pure nitrogen or top up of air as long as I know I've got the maximum amount of nitrogen I can get into them in the first place! Nitrogen has a higher boiling point than air so is better at keeping constant temps when tracking It's easy enough to make the filling hoses in fact I can use the filling whips from my scuba diving equipment, so looks like il be getting nitrogen bottle fills as we'll trimix when going diving At least I know where to get some for now, thanks guys.

The advantages of Nitrogen use for inflating tires is a lighter deflating wallet. Its complete BS aimed at people with more money than sense. I never top up my tyres either because the schrader is done up!. Do people ever check there done up?. £0.00 AIR +1

Then you are seriously in danger of running with progressively decreasing pressures. The valves primary purpose isn't for letting the air out - it's for putting it in. What do mean by "done up"? The only thing you do up is the dust cap - and the dust cap doesn't "do up" anything, nor help to retain the pressure in the tyre. It's just to do what it says - keep dust and debris away from the valve mechanism.

If you can be bothered....[ ] http://www.nitrofill.com/documents/Nitrogen-Tire-Dissertation.pdf As for never having to top up - I always thought tyres are permeable to gases - not a lot - but still permeable. And if reducing the amount the pressure increases with temperature is the concern, then getting rid of the water vapour is the main issue, as I understand it.

Firstly decreasing pressure would mean needing to re inflate so not sure where thats going??? Secondly a Schrader valve is removable and are hardly ever wound right in from the factory and will leak from the seal. Nothing to do with air in or out through the valve Mark. Have a look at a Schrader http://patentpending.blogs.com/patent_pending_blog/images/schrader_valve.jpg Your notice the pin winds out and if its lose will leak. Thirdly have a look at a Schrader valve key, Its not for tightening dust caps.

Alan, I read it diligently from beginning to end and noted that the EU think nitrogen in tyres is good... "Directive EC/94/95 of the Council dated 21 November 1994 (harmonisation of the legislation of the member states regarding the transport of hazardous goods by road) provides that use of deoxygenated air for tyre inflation is obligatory for road vehicles transporting hazardous goods, although if the vehicle is transporting the goods only within the national boundaries of the State in which it is licensed, it must comply with the provisions of local legislation" AND "Many manufacturers of industrial and earth moving machines recommend inflation with nitrogen as it reduces the danger of explosion due to excessive external heating, such as: "" The vehicle catching fire; "" Too abrupt braking; "" Extended brake application;" So point 1 is obviously an advantage to GT3 drivers (ho ho) Anyway the cost is trivial and each to their own, but I still would like to understand the answers to the questions I posed in post 10 of this thread

21% of Air is Nitrogen anyway I might add.[ ][ ][ ]

I thought it was closer to 70%, with 20ish% being oxygen?

Sorry your quite right Chris 78% according to google anyway. So I have about 85p worth of Nitrogen in my tyres for free[ ]

In answer to your question in #10 Ralph, I believe the correct tyre pressure is one where equal temperature is achieved across the width of the tyre after hard use. Too hot in the middle and it's over inflated and vice versa if the outer thirds are hotter. Of course camber has an effect too. Reading material here.. http://www.macgracing.co.uk/trackdays_setup1.shtml You could buy a temperature sensor - not very expensive - and play around with the pressures next time you go on a trackday[ ]