So what about all the atmospheric air surrounding the tyre that has oxygen in it then?
Sorry but using nitrogen instead of air is just a way of parting money from the gullible people.
At minus 2 this morning my tyre pressure monitor popped up saying low readings. Should be 33psi but 30 now. I understand Boyles Law so will not adjust the pressures.
Or should I pump them up to 33 now?
If they were nitrogen filled would the pressure have remained at 33 psi irrespective of temperature?
Or should I pump them up to 33 now?
If they were nitrogen filled would the pressure have remained at 33 psi irrespective of temperature?
In theory they should be increased - but I don't when the temperature drops below 7 C as I run my tyres higher than the recommended pressures anyway, 34/37 instead of 33/33.
Boyles Law applies to Nitrogen like any othe gas.
I check ours weekly and adjust wrt the pressure readings throughout the year. I will also check before a longer trip too. Since air is 80% nitrogen I cannot see a nitrogen fill being much different to an air fill.
The key point I was making is just about aircraft tyres and autoignition..... crudely put spontaneous combustion. The presence of Oxygen increases the risk of autoignition. Aircraft tyres can be subject to high temperatures - we've probably all seen smoke from landing gear on touch down. Equally its not unknown for brakes to seize and hence tyres are dragged down runways. These increase the temperature of the tyre, raising it closer to the autoignition point.
In the case of a mid-air incedent having tyres filled with Nitrogen is just one less risk of fire.
Yes, there is Oxygen in the surrounding air but the mxiture of volatile gases from the tyre compounds is going to be very much diluted and dispered. Of course once a fire starts on a tyre the surrounding air will keep it going.
There are other reasons for the use of Nitrogen as opposed to free air. Free air with oxygen carries moisture. Not only would this increase the risk of corrosion it may also degrade the tyre compounds more quickly. Nitrogen doesn't contain moisture - aircraft external temperatures at alititude can reach -50degC or lower. At these temperaturs the moisture would freeze - not a good idea.
Nitrogen also reduces pressure loss due to low permeation through the tyres and its less likely to cause pressure variations since there is no moisture present and its that that largely causes pressure differences.
None of which is really a concern for our car tyres unless you're paranoid.
One other point of using Nitrogen to pressurise aircraft tyres, is the high pressures involved, 150 to maybe 300 psi, depending on the aircraft.
Aircraft tyres also generate a vast amount of heat taxying around the airports. Aircraft, prior to take off full of fuel and passengers.
Baffled. This morning I noticed the second tyre on the van was flat. And as in the case of the first, which this thread is about, exactly the same issue. The valve could be pushed to one side and air leak out.
How unlikely is it the both wheels suffer the identical problem a month apart!
Never had a valve fail before on car or caravan. Both these valves were around 4 years old, the same as the caravan.
Gobsmacked! The fitter at the garage simply said rubber perishes. Mmmm.
And to add insult to injury when I said the tyre was from a caravan I was immediately "attacked" by another customer - an HGV driver. He seemed keen to let me know how angry he becomes when a - rude word- caravan is parked in HGV parking and the -very rude word- occupants were sitting outside having a cup of tea!
I simply said that I agree with him - generally. A HGV driver has legal requirements to abide by and no doubt deadlines to meet. "Quite right" said I.
I then asked him what his views were about the 3 mile overtake that occupies the center lane on a 3 lane motorway and stops me from passing!
Oh by the way, for those who thought I had asked to have my tyre inflated with nitrogen I hadn't. It just appeared on the bill. I have, however, made sure that this time I ONLY want a pressure of 65 psi and a balance!
How unlikely is it the both wheels suffer the identical problem a month apart!
Never had a valve fail before on car or caravan. Both these valves were around 4 years old, the same as the caravan.
Gobsmacked! The fitter at the garage simply said rubber perishes. Mmmm.
And to add insult to injury when I said the tyre was from a caravan I was immediately "attacked" by another customer - an HGV driver. He seemed keen to let me know how angry he becomes when a - rude word- caravan is parked in HGV parking and the -very rude word- occupants were sitting outside having a cup of tea!
I simply said that I agree with him - generally. A HGV driver has legal requirements to abide by and no doubt deadlines to meet. "Quite right" said I.
I then asked him what his views were about the 3 mile overtake that occupies the center lane on a 3 lane motorway and stops me from passing!
Oh by the way, for those who thought I had asked to have my tyre inflated with nitrogen I hadn't. It just appeared on the bill. I have, however, made sure that this time I ONLY want a pressure of 65 psi and a balance!
How to make friends and influence people! What was the response on the 3 mile overtake? Zilch I would guess.
Just picked up the wheel and tyre from the same Tyre Company (ATS Euromaster Chesterfield) I used for the first one. I was telephoned, as promised, at 10.30 am today and arranged to pick the wheel up at 11.45.
When I arrived the fitter in reception knew who I was, addressed me by name and then said he would carry the wheel over to my car! Very impressed since collecting the first one was quite a different experience. Paid my £20 and was simply told the wheel was outside.
With the wheel in my car boot I was gobsmacked to be told "No charge! "
"It's only a new valve and balancing!" and "I've put in a new high pressure valve."
I did tell him that the last tyre - exactly same valve problem - cost me £20 and included £3 for nitrogen fill. He was not impressed, and seemed rather taken aback and apologised - "Perhaps something to do with the accounting system," said he.
What a difference. Incredible. I can only explain that my impression of this young man from phone call to collection was very different from the impression I formed of his colleagues who had seemed totally disinterested and almost surly. He was polite, friendly and efficient - a credit to his employer.
Having said that you may wonder if the employer preferred a charge of £20 rather than a goodwill zero.
When I arrived the fitter in reception knew who I was, addressed me by name and then said he would carry the wheel over to my car! Very impressed since collecting the first one was quite a different experience. Paid my £20 and was simply told the wheel was outside.
With the wheel in my car boot I was gobsmacked to be told "No charge! "
"It's only a new valve and balancing!" and "I've put in a new high pressure valve."
I did tell him that the last tyre - exactly same valve problem - cost me £20 and included £3 for nitrogen fill. He was not impressed, and seemed rather taken aback and apologised - "Perhaps something to do with the accounting system," said he.
What a difference. Incredible. I can only explain that my impression of this young man from phone call to collection was very different from the impression I formed of his colleagues who had seemed totally disinterested and almost surly. He was polite, friendly and efficient - a credit to his employer.
Having said that you may wonder if the employer preferred a charge of £20 rather than a goodwill zero.
Checked the tyres this morning on both cars. The Rio were all spot on no change from last week. The XCeed three were all at 33 psi, nsf at 31psi. Quandary did I not check it properly last week? Is there a slow leak or did some road roughness give an instantaneous minute leak?
So pumped back to 33psi to recheck tomorrow morning prior to driving down to North Devon for a few days. This last couple of years I seem to have been beset by tyre issues. Valves x2 and punctures x2 with one requiring a new top spec Continental as the very thin sliver of metal had penetrated the shoulder of a tyre with only 6000 miles wear rendering the tyre not repairable.
So pumped back to 33psi to recheck tomorrow morning prior to driving down to North Devon for a few days. This last couple of years I seem to have been beset by tyre issues. Valves x2 and punctures x2 with one requiring a new top spec Continental as the very thin sliver of metal had penetrated the shoulder of a tyre with only 6000 miles wear rendering the tyre not repairable.
Given that they tyres and valves were original, and most likely fitted at the same time, and from the same batches, its quite likely they will have aged at the same rate and thus increasingly likely to expose any weakness that might have affected the batch.
I are ultra cautious when checking tyre pressures to try and avoid pushing the valve to one side to gain proper alignment for the tyre pressure gauge. With some wheel designs that is well neigh impossible.
Happened to us while on a rally at Sandy Bay in Weston. Went check air pressure all round before setting off and valve stem snapped. Had to wait for recovery to change the wheel before we could set off.
If you've ever dabbled in the wold of inflatable jockey wheel tyres you'll probable have had to bend the valves drastically to get the pump connected to top up! You have to wonder if this actually encourages leaks - mine certainly often needed topping up. Changed to a "kartt" and never looked back.
What did surprise me is that the fitter has used a new "high pressure valve". Looks a much shorter stem and hardly protrudes beyond the tyre, even with "TyrePal" sensor fitted. Wonder why such valves are not fitted as standard? I run at 65 psi.
When I thought about such valves on the caravan I seem to remember that around 65psi was mentioned as the maximum, and with motorhomes having pressures above that a HP metal valve was to be used. My caravan tyres were 55psi so I continued with the conventional rubber stemmed valves.
The difference was that those tyres have an inner tube so there should be no issue bending the valve?
The two valves that have been replaced developed a "tear" at the point where they entered the wheel.
Not sure if a similar point of fail would/could occur at the same place with an inner tube? You may well be right is suggesting it could't but there again had anyone told me two wheels/tyres would fail with a valve "tear" within a month of each other I doubt I would have believed them!
Bottom line is having to press the jockey wheel valve until it literally made a 90 degree angle with the wheel rim couldn't have done it much good.
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