NITROGEN IN YOUR TIRES.

[reed]

NITROGEN IN YOUR TIRES.
Dealers are putting nitrogen into tires they say it the best way to extend the life of your tires.
Nitrogen dissipates water keeping moisture out of the inside of the tire.Nitrogen does not expand
and contract so the tires will not deflate as with normal air and wear and tear on the inside of the
tire is minimized.
What do you think!
Thanks.
Reed.

[OldSwartout]

Most of that is hype trying to get you to pay more for the tire change. Few dealer/techs even understand the reason for using nitrogen, just that it became popular with race teams, so it must be a good thing.  Besides, they all have nitrogen tanks around from working on suspensions, so it is nearly free.

Moisture can not get through the rubber tire wall or inner tube, the molecules are too large. Whatever moisture is inside stays there and none gets in after you fill the tire. However, the nitrogen is absolutely dry when it goes in, so there is none inside if you use nitrogen, although there is little detrimental effect strictly from moisture, anyway.  The big deal with nitrogen is that the molecules are large enough that they are less likely to seep through the rubber over time and decrease your tire pressure.  When using air, some of the molecules do leak through the rubber and your tire pressure will decrease.  Using nitrogen means you can be lazier and not check your tires so often (probably a bad idea on a bike, but a good idea for the average auto driver).  

Nitrogen also does expand less with heat as some of the gases in air and the moisture have a higher expansion rate than nitrogen.  This is important on racing bikes and cars as there is better control of tire pressures throughout a long race, especially at the professional level.  The whole nitrogen thing is pretty much a waste on normal street bikes and cars unless they want to give it to you for free.  Even then, you should think carefully about it.  Most tire pressure recommendations from the manufacturers take into account the expansion with heat, so if they tell you 30 psi and expect 34 after a few miles at highway speeds, and you use nitrogen and have 31 psi after a half hour on the interstate, you are running underinflated.

Karl

[reed]

Karl
They put nitrogen in the tires on are B9 Tribeca Subaru because the TPMS light came on so i set the air pressures to the book.
And the light went off and no more problems.TPMS stands for tire pressure monitoring system.
So we will see.
Thanks.
Reed.

[OldSwartout]

It should go longer without leaking down. Watch the pressure rise after the tire temp comes up, should be less than it was. 

With air, my car will go from 30 to 34 psi after about 30 minutes on the interstate at 75-80 MPH, then level off.

[reed]

Karl
500 miles and the light is still off my wife is happy!
Thanks.
Reed.

[Toystoretom]

Snake oil......

The air is already about 80% nitrogen. The nitrogen that tire retailers use comes from a "nitrogen generator" and not a pure nitrogen tank. They couldn't afford to use pure nitrogen from a tank with the volume they need to do several hundred sets of tires a month. The nitrogen generator is a device that is supposed to filter out non-nitrogen gases, it's only about 90% efficient. When you mount a tire it already has air on the inside, they don't (can't) evacuate that out, the tire bead would break off of the rim. So at best when these guys tell you they are using nitrogen, in reality it is only about 90% or less nitrogen.

This is what dealers call a hook, they tell you that you must return to them (Costco is famous for this) to have your tires serviced properly. Bull....

So you see, it has nothing to do with any kind of theory about advantages, it only has to do with them making money. If you have never seen a guy mount a tire then you didn't see him slather the beads with a liquid lubricant (which is made from a premix... just add a bunch of water)  to help get the tire on the rim. Today's tires are mostly 17 to 20 inchers with sidewalls like steel so you need a bunch of lube, some of which ends up inside your tire. Nitrogen won't dry that thing out.

There is engineering dreaming and reality. Your tires get the reality. How are you going to test the air in your tires to see what is in there anyway? I can put green valve stem caps on your wheels and you wouldn't know the difference...

[reed]

Totstoretom
The guys at Subaru put the nitrogen in the tires for free and up to now the light is off!
I played with the tire pressures up and down and the light was still on.
And that's all they did put nitrogen in the tires and over 500 miles light is off!
So we will see.
Thanks for the input.
Reed.

[Toystoretom]

Your light is off because they simply set your pressures to the correct PSI. I could have done that with helium. The TPMS can't tell the difference between 134A and swamp gas.

[reed]

Totstoretom
I put the correct tire pressures in before  they put the nitrogen in and the light would not go off!
I think what Karl said it will go longer without leaking down!
Remember this is only a bit of fun.
Thanks.
Reed.

[OldSwartout]

Here's a good summary of all the myths and facts:

http://home.comcast.net/~prestondrake/N2_FAQ_Q11.htm

I was wrong a on a couple.....

Of course, who knows if he's right either 

[reed]

Karl
I have a Bridgestone tire engineer lives near me and he rates nitrogen in the tires etc.
Thanks.
Steve.