'Nothing wrong with using pure nitrogen. Problem is, it's not worth the extra effort and expense. The tiny bit of reduction in the rate of pressure loss just isn't worth it. If you have your own tank of nitrogen at home, then fine. But most people won't have that and running around finding a place with nitrogen (or not checking your pressure when you should because no nitrogen is available), is just too restrictive. And then there's the cost. Many places just rip you off. It's a cheap gas.

The value of using pure nitrogen has been way, way oversold.

 

I find sometimes poor flushing processes offered, so the full benefits aren't realaized.

Its been a staple in the karting world for years, where presure diviations = diameter changes= change in handeling dynamics.

Last time I was @ putnam park IN, Tony Stuart was testing a new chassis with an 1800 Kawasaki mill - and a huge tank (6ft tall) was present for his pressure adjustments.

Once its more readily available, and the flushing process is more standardized - I will be a big proponent!

Alex

 

My gas mileage has increased from 31 to 35 on the highway with nitrogen in my new tires...could be the new tires

 

now i have a question. When my mini service center replaced tires and I decided to try nitrogen I checked the pressure...the tires are at 42 I thought they were suppose to be 32?

 

Uhhh, that's too much pressure.

 

Should I hold Sterling Mini Va responsible if my tires fail..they have been on about 2 or 3 months. I will go deflate to 32...thanks for the response!

 

They won't fail you just got crummy suspension performance for a few weeks.

 

Cheers!

 

The Chevy dealer not to far from my house offers Nitrogen for $39.95 for the purging of the tires and filling them up. Then you can go anytime you think you need to and they check and refill if necessary free of charge as long as you have those tires. I had to plug a tire due to a puncture and they purged that tire and refilled it for no/charge.

Nitrogen works well here in Florida where in the winter the daily temperature fluctuates a lot during the day. It will be 35 in the AM and the low pressure light will come on. Then it will be 80 in the afternoon. I find with Nitrogen filled tires the pressure does not fluctuate enough to screw with the monitors no matter how severe the temperature change. Most Corvette people in Florida discovered this a very long time ago. I guess that is why the Chevy dealer offers it. The nitrogen also allows the tire to run a little cooler on very hot road surfaces.

If you do not think it is worth the $$$ just don't buy it. I,personaly think it is well worth using and $10.00 per tire for the life of the tires to me is pretty cheap for not having to look at the tire pressure lights every time the weather changes.

 

I looked to buy a Mini 2 years ago. The dealer tried to charge $199 with lifetime refills. Anyway, $20-40 is the going price. I have it in most of my cars.
It has it's advantages but is not a Must Have.

 

it's total BS. What is usefull is the reduction in water vapor content. If you want to know why N2 is being pushed so hard commercially, I wrote about it in my blog here.

Matt

 

+1

If you filled your tires with regular air on a cold dry winter day, you'd accomplish almost the same thing.

 

Good to know you can get lots of answers for whatever ails you

 

I'm seriously thinking about neon. Argon sounds cooler, but if I could get some clear rubber, the colors that neon would generate as the temp of the tires changes would be WAY cool...

 

 

Xenon would make the tires match the headlights (if you got Xenon headlights, that is).

Maybe radon would glow better than neon?

 

Mabey I don't understand you post, what is total BS? Its neems N2 is what is BS, yet you mension is primary advantage immdiatlety afterwards.

N2 extractors/ seperators are realtivley low cost when you consider how quickly they can pay for themselves, & they are relatvley low maintainence pieces like an air compressor. Your only ongoing expense is the cost of the electricty to run the unit.

This means than anything you charge for N2 less your electrical expenditure+ tech's time is pure profit. This means you can get out of the red on your initial investment, quicker -

Yes it is a $ maker with a minimum 85 point margin, if you charged $10 a tire - and took time to flush it correctly into your sealed enviorment.

Its not just an extractor, you need a good vaccum pump, and cylinders.

This V pump could also be used for AC service, further adding value to a shop's investment - and getting into black even quicker!

The containment cylinders + manifords need to stay job specific - to avoid refridgerant contamination.

To me the only BS on n2 is the lack of SOP to ensure a atmospheric free enviroment or how often proper procedure, and the assoicate equiment cost can (would be) be cirumvented.

Your customer will not know if you did n2 correctly, only racers with n2 experince would know - and those guys likley wouldn't be paying a shop for its N2 - they'd be doing it themselves.

If you have the charge cylinders dedicated to tire service, you could pull your bars, and with ratchet straps + an refridgerant service manifold dedciated to your N2 persuits - You could ponetially do it right in 5 minutes a tire, add 5 more minutes if you want to re-purge your inital charge leaving you a healthy 80 points.

(Only real detail nuts would go this far, if properly vaccumed in the 1st place - and if your really concered about $ savings you can recycle your 2nd purge!

Once its an industry standard, it should be handled better like runflats. In 1997 they only expeirced tire guys with RF sidewalls were Chevy dealers. 10 years later runflats can be serviced at most tire dealers.
Lets just hope runflat design technology develops at that same rate

Alex

 

Excellent idea! But I think I'll take it a step further--I'm going to find a tire with three valve stems, and mix Argon, Neon, and Xenon, and have the best of all three worlds!

I looked into Radon, as apparently my basement is a cheap and reliable source, but the EPA frowned on it...

And of course, I'll be putting some high-quality spinners on there as well.

 

You really only need 2 stems, and know the mass/weight of your gasses. Fill in order, and let gravity help! & then drive and ......

 

Actually, there is more to it than the size of the molecules.
Nitrogen molecules are only 3% bigger than oxygen molecules, yet the permeability in natural rubber is 3-4 times greater for oxygen than nitrogen,
which is much more of a difference than predicted by the size of the molecules themselves.
Bottom line is with air, you lose about a 50/50 mix of N2 and O2 (at first - this ratio changes slowly as you lose more air and the
gas in the tire becomes more nitrogen rich over time).
Typically one will lose about 4 psi per year with air vs. 2 psi per year with N2 (at the same cold tire pressure). Consumer reports ran this test and got about those results.
The amount of water vapour present will not affect the loss of gas in the tire much, but will cause a greater fluctuation between hot and cold tire pressures.

 

Its been our experience that pressure losses over a year would be more significant than stated above based on atmospheric charge.

Each shift of 10 degrees F will equate to 1 lb pressure variation. If you live in a climate that is the same all year (equatorial proximity) this is not a factor. the NA in Nam sugests most users will have temperate fluctuations.

Due to air's migration influced by numerous heat cycles of regular use - 1 lb loss per month is typical - RMA

Alex

 

Nitrogen isn't the benefit. It's the reduction in water. Dry air will do the very same thing.

Oxygen and nitrogen have effusion rates that differ only by a few percent. And guess what. Oxygen effuses slower, not nitrogen. This has to do with molecular mass, and oxygen is heavier than nitrogen, so at the same temp, it moves slower by a few %, and has less collisions with the tire wall, by a few percent. It also has less collisions with other molecules when effusing through pores, or diffusing through other gasses. This is pretty simple physics.

All the marketing arguments about nitrogen having a more stable pressure imply that it is the nitrogen that is the cause of this, not the vapor pressure of the water content.

All the marketing arguements about nitrogen having a more stable pressure because of erroneously quoted effusion rates totally ignore the leakage at the bead due to hard cornering, or leakage at the valve stem. As others have posted, this is a real contributor and is totally ignored by the proponents of nitrogen filled tires.

What is true and is totally backed up both by the Wards Dealer article and your own post, is that nitrogen is directly profitable for those selling it, or indirectly profitable for those that give it away as a marketing tool to bring customers into shops.

Also, the "correct filling" is a bit of a red herring. Say your tire is full of room air. 22% stuff other than nitrogen. Deflate to atmospheric, inflate to 30 lbs with nitrogen. Now it's down to about 7% stuff other than nitrogen. Do it again, it's down to about 2% non-nitrogen. Do it again, and it's about 2/3rds of a %.... At four times, the levels are so low that they don't matter at all. No need for dual valve stems or vacuum pumps. Even if you use dry air, the same progression holds. The water vapor is removed via mixing with what has no water vapor in it, and is expelled when released.

Really, the benefit is from dry air. There are lots of ways to do this (like using a water trap with the compressor, or running the compressed air through a tube of kitty litter!). For all of us that aren't at the very cutting edge or racing or flying jumbo jets, nitrogen is just a marketing game. On another site, a poster on this very same question had bought lifetime nitrogen fills for $160 from the dealer! After a while, he got them to change it to a service credit because he'd learned that he'd been ripped off.

Matt

 

Well said!! I just can't believe that people are getting sucked into this nitrogen thing. (Well, maybe I can. What did P.T. Barnum say?)

 

If you lack O in a mainly H atmosphere, you can't make h2O - your arguing semantics. If that makes you - then so be it.

I have a dryer for pressurized painting in line on my compressors' output. This drain line drips moisture every time I run the compressor. I never store any pressure in my tank or hardlines, I bottom drain the tank every time.

For street cars- this is plenty for me.

I used to race enduro karts, I am a big boy, so I was never compeditive due to shear mass.

If I didn't run N2 in my kart tires, My hadeling dynamics would be all over the place as tire shape and measurable diameters change with pressure in karts. You couldn't set up for a specifc track's requirements if you can not control your diameters.

My N2 enviroment, was O and H2o free - so my diameters were pretty constant.

With my dried atmospheric charge in a kart, my diameter diviations were so significant I could not set up for predictable handeling dynamics inside a 30 minute sprint race.

My beef with your presentation, is all your spin. Were saying the same thing. Do I pay for N2 in my car? not currently.

Would I for the kart? @ 250+ lbs me being 70% of my kart's wet weight - you betcha!

 

Alex - Did you ever try running the Kart with "dried" air in the tires and if so did that help? I only ask because you said you had a dryer on the output of your compressor.

I'm just curious. Even in an autocross on street tires I can increase the pressure in the outside tires about 1 psi/run as the tire heats up. Nitrogen would presumably help with that buuuuuut there's a multitude of (practical) reasons I can't run nitrogen in my tires at an autocross.