I was a tractor trailer driver for a major trucking company based in Montreal in the mid 60s and we used all Michelin radial tires except on the steering axle. It took real strength to turn a steering wheel in those days and radials would have made it worse. We used Michelin lug radials on all the drive axles and they were the best tires around in the snow. Around 1972 Firestone made them an offer to save them a lot of money on radial tires. Firestone set up test equipment at the gate in Montreal, taking tire temps.
After two months the company had so many tire failures that the President threw Firestone out and told them to buy their own trucks to learn how to make tires with.
Consider this: You fill your tires with nitrogen. But your tires already had air in them, at around 14.7 psi. In order for the nitrogen to completely replace the air, youād need to evacuate the air first. How do you do that? You canāt just suck all the air out, because then youād break the bead. Youād need two valve stems - one takes on the nitrogen, the other evacuates the air.
They actually make wheels with two valve stems. Do you own a set? Because if you donāt, ermā¦ youāve got air in your tires whether you filled with nitrogen or not.
As the others have noted, nitrogen for most applications is silly. I only have ānitrogenā in my tires because Costco wonāt put normal air in them.
Boy oh boy I finally met an expert!
Let me give you the definition of an expert.
break it down
ex or X is an unknown
and spurt is a drip of water under pressure.
So an expert is an unknown drip under pressure.
If you are running your car with 14.7 p.s.i. those tires will not last as long as properly inflated tires,
Your analogy is way off the mark.
Put your car on a lift.
Mount the tire on the wheel, put the wheel in the car.
How many P.S.I.s are in that tire, before you inflate it?
Seltzer bottle with an air charger, or whipped cream bottle with an air charger or air rifle with an air charger, run all the seltzer out, and yes there is air in the bottle, but it has no Pounds per square inch. An empty bottle is just empty.
I made nylon for 18 months and we had a vessel that was 5 stories tall, that held 40,000 lbs of molten product and right next to it was another vessel with 40,000 lbs of molten product in it.
You heat this product up caprolactam and keep it under pressure then under vacuum for a period of time and the result is Nylon 6.
But this product is terribly fussy about being heated so it has the possibility of turning any air in the vessel into a black stalactite, so in order to stop any air from entering the vessel, we had a constant Nitrogen sweep over both vessels. Nitrogen is heavier than air, that is why it can replace air in a vessel or in a tire.
And get your tires filled with at least 30 p.s.i. more if you have an SUV.
If I read that correctly you are saying to make tire inflation 30 psi higher than the recommended pressure on vehicle label. Meaning if 32 psi is listed for vehicle you would inflate to 62 psi. If that is what you mean then it is wrong and dangerous no matter what the vehicle is.
@shadowfax did not say he was running his tires at 14.7 PSI. He was pointing out that even when you fill a new tire with Nitrogen, there will already be approx. 14.7 PSI of regular air already inside themā¦ (feel free to correct me if I misinterpreted @shadowfax!)
Before the battle begins over 14.7 psi, perhaps itāll help to realize that 14.7 is considered standard ambient air pressure (at sea level, at 23C, etc. etc.). A tire mounted on a rim without a valve stem is at 14.7 psi. That is an ABSOLUTE air pressure.
Your tire gageās zero is actually referenced to ambient air pressure. 32 PSI tire pressure is not the absolute pressure, itās the pressure above ambient. Its absolute pressure is 46.7, but it has 14.7 psi pressing evenly against the outside of the tire from ambient air, so the difference, considered the tire pressure, is 32 psi. That is the pressure that the tire is filled to over and above ambient.
Are you suggesting that buoyancy allows the oxygen and misc components in the ambient air to somehow exit the tire when you add nitrogen through the tire stem? Would you mind explaining how?
And, while youāre at it, since thereās that much buoyancy in action between oxygen and nitrogen, would you mind explaining why the two donāt stratify in ambient air?
This statement is just downright dangerous. You should never exceed the maximum pressure recommended by the tire manufacturer under any circumstances. You should fill your tires to the pressures recommended by the vehicle manufacturer. Itāll be posted on your door jam and in your ownersā manual.
I may have missed it but no mention yet of molecule size. O2 is small and N2 is huge in comparison. O2 leaks out THROUGH the tire material while the N2 stays behind. Always wanted to have a tank of N2 to top up my bike tires to eventually have pure N2 inside. Also not mentioned are airliners and NASA use N2 because of its stability over a wide temperature range. Additionally, the commercial N2 machines use a mechanical āsieveā separator as the main device. There are thousands of āsoda strawsā to filter ambient air to get N2. Tire pressure diminishes in cold weather because the 21% O2 gets a lot smaller a lot quicker than the N2.
Getting confused, ambient air pressure 14.7 at sea level, 12 in Denver, but a tire mounted with no air added will read 0 psi at both locations? I assume that is before the tire is resting on the ground, to which my guess is there would be an increase in PSI relating to the actual weight on the tire, so in denver for the same car a greater volume of air would be required to get it up to say 30 psi?
Not true. The kinetic diameter of N2 is 364 picometers, O2 is very slightly smaller at 346 picometers. Consumer Reports tested N2 vs. air loss in tires, found almost no difference after a year.
And nitrogen is LESS DENSE than oxygen, @Egide_Beaudoin - youāre exactly wrong, again.
I use my home compressor to fill my tires because Iām very particular. I use a mix of 78% nitrogen but then I add about 1% Argon and 21% oxygen. Seems to work for me. Thanks Barry.
I apologize. Itās below zero here, New Years Eve and too cold to go anywhere, but safer that way. So Iām getting a little sarcastic thinking about that 5 million Bill Gates is sending me.
I guess the bottom line here is that the OP is sold on nitrogen. Science doesnāt matter. Seeing as nitrogen is certainly safe to use in tires, I support his right to use it. I just wish heād refrain from recommending things like āif you have an SUV add 30 pounds moreā. His other statements may be bad science, but theyāre harmless. That one could be dangerous.
Texases got me! He is right about the size of the molecules. So, in searching for info I find that Michelin claims N2 escapes 20 to 30% slower than O2. They also say it does not respond to temperature changes as radically as compressed air.
I know for a fact that oxygen, nitrogen, and argon are identical in how they expand and contract with temperature. The only possible reason for them to say this is the potential for water vapor to condense. But thatās only about 1% of the total at most, so thatās only 0.3 pisi change caused by water condensing.
For safety and exact pressure control. One does not want tires full of pressurized oxygen and nitrogen popping during a crash, feeding a fire. And setting pressures exactly from a high pressure N2 cylinder may have benefits in critical situations. Neither apply to our cars. Both reasons are also why race cars use N2.
Iām thinking Michelin mentions N2 because some tire dealers make a lot of money from it, and they donāt want to get in the way of that cash cow.
No, that is not what he wrote. This is what he wrote. ā
By separating that statement into two sentences youāve changed its meaning.
OP, would you please clarify? There seems to be two interpretations of what you meant. If you meant to put in a period and capitalize the word āmoreā, making this the statement that Nevada implied, please let us know.
