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nitrogen is an inert gas so it tends to stay at the same tempreture , thus the tyre doesnt increase in pressure when the rubber gets warm on contact with the road surface , thence remaining at the correct pressure to minimise tyre wear (i think)
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nitrogen is an inert gas so it tends to stay at the same tempreture thus the tyre doesnt increase in pressure when the rubber gets warm on contact with the road surface
I think it'll Boyle.
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"I think it'll Boyle."
Get yer coat ;-)
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Get yer coat ;-)
I'm sorry. I couldn't resist it. Can't stay here gassing, anyway - I'm off for a bacon sandwitch with brownian sauce.
Ooops.
Sorry.
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nitrogen is an inert gas so it tends to stay at the same tempreture thus the tyre doesnt increase in pressure when the rubber gets warm on contact with the road surface thence remaining at the correct pressure to minimise tyre wear (i think)
Your partly right, but I think you must have been skiving some of your Chemistry classes ! Nitrogen is an inert gas, but will expand on heating according to Boyles law just like air/oxygen etc.
The main reason for using Nitrogen in tyres I think is that it is less susceptible to leakage unlike air, and as such keeps the tyre pressure constant for a very long time, hence improved tyre wear. But the claims they make are overblown ie 50% better tyre wear. I suppose if you are the sort of person who drives around with 8 PSI in your tyres then this claim is true.
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nitrogen is an inert gas so it tends to stay at the same tempreture thus the tyre doesnt increase in pressure when the rubber gets warm on contact with the road surface thence remaining at the correct pressure to minimise tyre wear (i think)
Since plain old air is over 70% Nitrogen anyway it seems like a waste of money to me
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I've had Nitrogen in my bike tyres for the last twelve months.
It made no difference to wear, grip, comfort, handling, fuel economy or top speed.
The single difference I did notice was with normal air, the front tyre needed frequent checking and pressure adjusting. With Nitrogen this was not the case.
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With very few insignificant exceptions, the physical performance of a Nitrogen-filled tyre will be identical to the physical performance of an Air-filled tyre.
These are the only exceptions I can think of:
(1) A tyre filled with Nitrogen will be slightly lighter than a tyre filled with Air.
The calculation to demonstrate this is:
(14.0067/15.999 x 21) plus 79 = 97.38
Where:
14.0067 = Atomic weight of Nitrogen
15.999 = Atomic weight of Oxygen
21 = %age Oxygen in Air
79 = %age Nitrogen in Air.
Conclusion: the weight of Nitrogen in a Nitrogen-filled tyre will be 97.38% of the weight of Air in an identical Air-filled tyre at an identical pressure.
(2) In the event of an explosive F1-type collison, a burst Nitrogen tyre would release a cloud of Nitrogen that may slightly quench flames, but it would disperse in a very few seconds.
(3) There may be very slightly less 'corrosion/oxidation' to the inside of the tyre-wall and the wheel edge covered by the tyre. But I suggest that this would be insignificant, when does anyone replace a tyre because it's worn out from the inside, or a wheel because it's corroded under the tyre?
Nitrogen is not an Inert Gas. There are lots compounds containing nitrogen (eg Ammonia, Nitrogen Oxides). However it is true that Nitrogen is less reactive than is Oxygen.
I wish to state that virtually all of the stated benefits of Nitrogen-filled tyres on this thread and the linked-thread are just plain rubbish and I wish I had a pen with green ink that I could scribble all over them with. Pah!
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But would it make sense to fill just the spare with nitrogen?
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As has been mentioned before, aircraft tyres are filled with dry nitrogen from bottles. As well as the pressure change with temperature being less, the danger of water in the tyre is reduced. Aircraft wheels are subjected to very low temperatures at altitude, so any moisture would freeze. Upon landing, the ice could seriously unbalance the wheel, causing vibration, tyre failure, directional instability etc. When fitted, the tyres are purged repeatedly to remove almost all moisture and oxygen.
Whether the benefits of nitrogen for aircraft are transferrable to cars is debatable. They are not usually exposed to sub-zero temperatures for hours at a time and then required to instantly perform to their maximum specifications.
It sounds like another case of technology creep.
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It sounds like another case of technology creep.
The links I provided in an old post:
www.honestjohn.co.uk/forum/post/index.htm?v=e&t=15...9
no longer work, but I have sourced some updated ones via a google search.
www.merityre.co.uk/car_tyres.htm :-
Tyres filled with Nitrogen will maintain their correct pressure for longer, because Nitrogen doesn't leak through the tyre's structure. Normal compressed air contains Oxygen and water vapour, both of which permeate through the tyre casing.
www.blackcircles.com/general/technology :-
The rubber tyre is like a membrane, through which oxygen permeates three times faster than the nitrogen. The result is that the oxygen slowly leaks out through the rubber walls, and the under-inflation leads to higher tyre wear with a consequent decrease in safety and comfort, and higher fuel costs.
On the flipside however:-
www.tyresave.co.uk/nitrogen.html
I will end by saying that both my rear tyres are nitrogen filled (after having a couple of punctures repaired), and the fronts are bog standard compressed air filled. Every time I check the pressures (approx once a month) it's only the fronts that have needed air adding to them.
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and a further link from an old posting
Read all about it
www.uniflate.com/
and who has the system
www.uniflate.com/index.php?option=articles&task=vi...3
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Er ...... is n't "air" already some 70% nitrogen?
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Just think you could market a new super product 70%nitrogen 20% oxygen and 10%secret additives sold in any size container you like with untold uses.
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Nitrogen ! ! !
So when i fill with air I fill with 80% nitrogen, the oxygen leaks out, I refill the missing 5% with 80/20 N2/O2 (Now I have 84% nitrogen . . . this is repeated each time I top up and the percentage of nitrogen increases each time.
After a few months I have mostly nitrogen in the tyres without paying any extra!
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How about filling with carbon dioxide? offsetting personal `carbon footprint` into a tyre footprint.
Propane sounds more exciting.. Giving the possiblity of tracing a slow puncture with a match............ :)
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Propane sounds more exciting.. Giving the possiblity of tracing a slow puncture with a match............ :)
...the heat from the flame will melt the rubber and fix the puncture too. Pure genius !
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Cool - the tyres on my supra are about 6 years old - I must be getting close to 99% Nitrogen by now!
This kind of stuff reminds me of shampoo adverts - "now with added nano particles and aqua proven to give a 27.45% increase in percieved shine"
Forget the Nitrogen and use the money saved to invest in a decent footpump or mini compressor.
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Use Helium, to reduce unsprung weight. Tie the car down though, when you get out.
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Use neon, add a discharge device and out pimp the Saxo lads. But only if you have translucent tyres....
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Cool - the tyres on my supra are about 6 years old - I must be getting close to 99% Nitrogen by now!
If they really are, then replace them pronto. Tyres don't have an indefinite lifespan, and will crack and perish. And your Supra is hardly a shopping hatch....
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Yes, very good point - the car spends 99% of it's life in the garage which is heated in the winter and I even run a dehumidifier to keep the damp down. I keep a close eye on the tyres and so far I've not seen even a hint of cracking (so far). I only average around 1k miles a year in it, so at this rate it will be a while before they need replacing due to the tread wearing out.
Could be a good excuse to book a track day for some hooligan behavior to wear those tyres out :)
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Tyres filled with Nitrogen will maintain their correct pressure for longer because Nitrogen doesn't leak through the tyre's structure. Normal compressed air contains Oxygen and water vapour both of which permeate through the tyre casing.
In which case if you keep topping up with air, you will eventually end up with almost pure nitrogen in the tyre.
{ Crux of DD's quoted post remains so that using keeps your reply in context ! - PU }
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There is an awful lot of rubbish in some of the above thread about nitrogen.
Nitrogen is not an inert gas!
Nitrogen will not extend the life of a tyre if that tyre does 40k miles per year and as such become quie expensive. It may extent the life of, say, a caravan tyre as these stay in contact with the more 'harmful' oxygen for far longer (several years).
Unless you dislike the tyres you currently use, I would stay with the same.
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wotspur doesn't need nitrogen in his tyres - he is getting good mileage as it is - if someone hadn't told him two were worn on sidewalls -one had a split and thickness was down to 1.6 on one or more I dare say he would have got another 10k out of them -that's of course if the 30% left of brake pads would have lasted that long ??????????????????????????????????????????????????
Nitrogen seems to be last thing required here
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What are you getting at here dxp55 ???
Are you suggesting if it hadn't been for the meddling mechanic he could have saved a few quid :)
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I am not suggesting anything of the sort - for someone who does 40k a year and then have someone tell him his tyres are well past it is not doing his morning checks or weekly checks come to that -
To come on here and admit you have four duff tyres -30% left of brake pads -carry heavy loads and do 40k a year to me is irresponsible. -I have no objection to people putting their own lives at risk but imagine having to brake hard in wet and find a vehicle with these tyre and weight behind you !! By all means ask for a view on best tyres to buy we all need a bit of help sometimes -but we all need to take responsibility for the upkeep of our vehicles.
I am sure wotspur is a safe and courteous driver but the unexpected can always happen.
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I'll take my tongue out of my cheek now.
You are right though dxp55, people should be taking more responsibility for the upkeep of their cars. That's why extending MOT's to two years would not work in the UK. People use that as an annual checkup and if it passes think, Great ! don't need to look at it again for twelve months.
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The other thing is that when the tyre is actually "put on" the rim, there is 1 atmosphere's worth of pressure of oxygen in it.
If the tyre is inflated to? what? 2 atmosphere's pressure? then there is still 10% oxygen in it, innit?
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I'll correct that myself, before anyone else does!
There's still 7% oxygen in it.
(2 atmospheres over atmospheric)
Sorry!
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Yep your right DXP55 I don't check on a weekly basis, but nothing was mentioned when I had it serviced 9 weeks ago, but with 500-1000 miles a week,recently the damage could have occurred at anytime.
Anyway after alot of web site research, blackcircle,merittyres,mytyres and several others I was quoted from 116 for supply only to 185 for supply and fitting, I finally got all 4 done for £565 fitted, tracked and balanced from my local K.F, (within walking distance from home ), so Iwas quiet happy, though it still hurts. They do a local price match with their major competitors, if you ask.
Thanks for all your help- brake pads should be ok for another month or two.
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i think this nitrogen thing is a lot of hot air
wotspur lots of miles,please check your tyres more often,if the last service you werent warned tyres were low then i suggest you take your business elsewhere,every tyre is 3 points and death by dangerous vehicle is worse ,never mind your life in ruins and someone elses.kwik fit now have a data system for companies where all tyres for all company vehicles can be monitered,could you consider joining the scheme?
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Nitrogen is not an inert gas!
but tis a noble gas me thinks !! richard (noble) used it in his tyres on thrust 2
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Pete M: "As well as the pressure change with temperature being less"
From "O" Level physics, the combined gas law says: P1.V1/T1 = P2.V2/T2 - N mention of what gas is involved, so the pressure change will be exactly the same for any gas that changes its temperature by a given amount.
V
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Before changing my tyres, the car continually verred to the left , (checked it going along the A3), so had it all balanced and wheel alignment, but it hasn't made any difference -is it likely they didn't actually do it, difficult to prove, or is it more likely to be another reason ??
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