Inflating tires with nitrogen?

[justinf]

Does anyone have experience with this? I was reading an obscure article in an auto trade mag while waiting on my oil change today, and they were talking up new tires inflated with nitrogen. Better pressure retention was one benefit mantioned. The article stated that most of the '05 TdF riders did so. . . huh?

[Fixed]

bro next it will be tire test i.m.h.o. cheers :beer:

[spiderlake]

I've heard helium is the next big thing in '06.......

The Army (IIRC from my soldiering days) uses Nitrogen in their tires and I believe a lot of airlines do too..... Can't recall the specifics behind why but I have heard of it before......

[pale scotsman]

Airplanes use nitrogen to fill their tires as well. Nitrogen isn't as susceptable to changes in temperature and pressure as good 'ol air is, so the tire pressure is more consistant.

[fiamme red]

Your tires already contain 78% nitrogen.

[SpongeDad]

Airplanes use nitrogen to fill their tires as well. Nitrogen isn't as susceptable to changes in temperature and pressure as good 'ol air is, so the tire pressure is more consistant.

I don't think that's it. At the pressures we're talking about, I think all of the gasses are pretty well described by the ideal gas law: PV = nRT.

I believe it's simply better gas retention. From the Ingersoll Rand website

"Better air pressure retention. The single biggest reason for tire failure is lack of maintenance of tire
pressure. In fact, 54 percent of all vehicles on the road have low tire pressure. Oxygen in compressed air can permeate the tire wall reducing tire pressure. With nitrogen, diffusion is 30 to 40 percent slower than oxygen. As a result, nitrogen maintains tire pressure longer than ambient air."
http://irtools.com/products/nitrogen/

Honestly, how hard is it to pump up your tires every day or two?

[BBB]

Didn't Ullrich use/try helium to inflate his tyres around the time of the '99 Vuelta or World Championships?

[Ken Robb]

auto racers and autocrossers sometimes use nitrogen because it doesn't increase pressure as the tires heat up as much as plain ole air does so tire pressure is more consistant lap to lap. It has nothing to do with slower leakage.

[Brian Smith]

auto racers and autocrossers sometimes use nitrogen because it doesn't increase pressure as the tires heat up as much as plain ole air does so tire pressure is more consistant lap to lap. It has nothing to do with slower leakage.

There could be both benefits.
Obviously for someone using tire inflation pressure as a tuning variable, the close retention of that same pressure a week later means very very little, but for someone trying to maintain fuel economy and safety between fuel fillings, longer term pressure retention means something valuable.

[Ken Robb]

I guess I wasn't clear. I don't think there is any slower leakage with nitrogen it just doesn't expand/contract as much with changes in temperature. The largest temp variations are caused by agressive high speed driving not usually ambient climate temp changes.

[SpongeDad]

auto racers and autocrossers sometimes use nitrogen because it doesn't increase pressure as the tires heat up as much as plain ole air does so tire pressure is more consistant lap to lap. It has nothing to do with slower leakage.

Do you have a website for that? I don't believe there is any difference in the expansion of nitrogen vs oxygen (again for any gas, Pressure * Volume =(number of moles of gas) * a constant -R * Temperature). Here's a web article that references racing - nitrogen is used to deal with leakage issue. http://www.winnipegfreepress.com/autos/story/3240342p-3752000c.html

This cite claims that the use of nitrogen is to avoid the moisture in ambient air (http://auto.howstuffworks.com/question594.htm) - that I could believe. As temperatures rise a small amount of liquid water aspirated into the tire could turn into gas, increasing the pressure in the tires.

[classic1]

Didn't Ullrich use/try helium to inflate his tyres around the time of the '99 Vuelta or World Championships?

East European track teams were doing it in the 70's

[cycleman_21]

I can see it now, at the next big charity ride guys opening up thier trunk and pulling out big ole tanks of specialized gasses to inflate tires :p :p :p :bike: :beer:


RC

[BdaGhisallo]

I remember reading that the Telekom boys used nitrogen to inflate their tires back in the '97 TdF. I guess that didn't want the tire pressure on Riis' Pinarello Montello to vary as he chucked it into the trees in the final TT!!!

Seriously, though, I remember that they said it was for a very specific reason. I can't recall that reason, though!

[Kevan]

I can see it now, at the next big charity ride guys opening up thier trunk and pulling out big ole tanks of specialized gasses to inflate tires :p :p :p :bike: :beer:


RC


Supposedly, it's to balance the pressure throughout the tire. Course, when I tried it my tires already had air in them and despite deflating the tire first, there was still air in them. Didn't feel anything different from plain ol' air. Bunch a hooey I say.

[William]

I'm using Nitrous Oxide. I don't feel anything different in the ride. But if I need cheering up........everything is alllllllllllrrrrright. :banana:



William ;)

[Gothard]

Nitrogen molecules are larger, thereby slowing the inevitable tiny leaks that deflate the tires over time.
Nitrogen is indeed more temperature stable which is a benefit for any track car driver.

[PaulE]

If you buy auto tires at Costco, they will fill them with nitrogen and put a green valve cap on! :)

[Ken Lehner]

Nitrogen molecules are larger, thereby slowing the inevitable tiny leaks that deflate the tires over time.
Nitrogen is indeed more temperature stable which is a benefit for any track car driver.

Which part of PV=nRT don't you understand? The volume is nearly constant in a tire, therefore pressure is directly proportional to temperature. That's independent of the makeup of the gas in the tire.

If you look at the periodic table, you'll also note that nitrogen atoms are smaller than oxygen atoms. You'll also note that carbon dioxide molecules (in those cartridges) are larger than nitrogen atoms (N2), yet, carbon dioxide leaks faster (because of chemical properties, not size of molecules).

[Ken Robb]

Dear Sponge, Thanks for your link which says that it's the water content of plain ole air that contributes to the additional pressure variation caused by temperature changes. All I know is that serious racers check their tire pressures before every session so they don't use nitrogen to reduce leakage. They do want their tires to perform as uniformly as possible from the beginning to the end of their time on the track and they find that inflating with nitrogen helps achieve that.

FWIW, I check my bike tires before every ride and find big differences in air loss depending on the tubes used. Ultra-light latex, not surprisingly, loses air very quickly. When I use regular 18-23mm tubes in 27mm tires they leak faster than the same type tube in the 27-35mm size so I guess the more we stretch the tubes the more the "pores" in the rubber open and the faster they leak down. I also find consistant variations between different brands of tubes that are supposedly the same type and size. It's not enough to matter but I might have to add 10psi to one tire and 5psi to the oher when they were both the same pressure a few days earlier.

[PanTerra]

Just make sure you change the air in your tires, the stale air runs a little less lively. :p

[palincss]

I'm surprised weight weenies aren't using hydrogen instead of either nitrogen or air. :banana:

[flydhest]

palincss,

steer them towards helium instead of hydrogen.

Mavic instead of Hindenberg.

[Ken Lehner]

Just make sure you change the air in your tires, the stale air runs a little less lively. :p

Good suggestion. Also, be sure to regularly rotate your wheels that are hanging on a wall, so the air doesn't bunch up at the bottom. That really throws the wheel balance out of whack.

[JohnS]

I use the hot air expelled by some members of this forum. :)

[CarbonCycles]

You guys might be thinking of the reactive properties of Nitrogen versus "air". Air is an oxidizer whereas nitrogen is inert. The reasoning goes that "air" reacts with the metal/rubber within the tire thereby causing release of pressure...nitrogen will not react and rather keep the pressure more uniform.

[Gothard]

Ken,
First of all, very diplomatic ways... :rolleyes:

Second, you are right :beer:

[Ken Lehner]

Ken,
Second, you are right :beer:

For a change...

[Samster]

I'm using Nitrous Oxide. I don't feel anything different in the ride. But if I need cheering up........everything is alllllllllllrrrrright. :banana:
William ;)

Reminds me of my childhood dentist... Ah, the good-old-days... When getting cavities was fun. :o

[flydhest]

Reminds me of my childhood dentist... Ah, the good-old-days... When getting cavities was fun. :o

When you grow up, filling cavities is more fun.

[Samster]

When you grow up, filling cavities is more fun.

is the dentist getting the nitrous?

[manet]

When you grow up, filling cavities is more fun.

self fulfilling prophecy?

[manet]

is it safe mr. bean?
http://images.google.com/imgres?imgurl=http://www.fortunecity.com/bennyhills/mrbean/198/beant.jpg&imgrefurl=http://www.fortunecity.com/bennyhills/mrbean/198/pics1.html&h=94&w=37&sz=2&tbnid=hYId430DeZoJ:&tbnh=75&tbnw=29&hl=en&start=8&prev=/images%3Fq%3Dmr.bean%2Bdentist%26svnum%3D10%26hl%3 Den%26lr%3D%26sa%3DG

[flydhest]

self fulfilling prophecy?
don't you mean:

self (ful)filling prophecy?

[manet]

don't you mean:

self (ful)filling prophecy?

hey, you're the expert

[BumbleBeeDave]

. . . the helium probably works better--at least, according to MY source.

BBDave