Nitrogen filled tyres

Trawling the net today, l found an article by the New York Times on filling your tyres with Nitrogen. Initially, the thought grabbed my imagination. The argued benefits of using nitrogen gas seem to be that it has a linear expansion characteristic which allowed the tyre to keep its pressure better over a longer period of time. While a homogenous gas offers linearity across the various temperature changes of a day, pressurized air is suggested to be unstable when faced with the same working temperatures across the temperature variation of a normal day. The suggestion therefore is that, pressurized air looses pressure quicker than nitrogen filled tires, thus causes harsher tyre wear and degradation than Nitrogen.The downside of using nitrogen is the cost of a pump up. To benefit from the homogenous linearity promised by nitrogen, one must top up only with nitrogen once converted to nitrogen. Finding somewhere that offers nitrogen service will most likely be difficult.

A head to head test between Nitrogen and Pressurized air was conducted by a contributor to this article and suggestion was that the advantage was slight. It would make sence that this is the case since 78% of ordinary air is nitrogen. The advantage recorded in a car based trial over a year test period suggested an 8% advantage for nitrogen. I wonder what a similar study will show for a bike based test.

Mind you, the test indicated in the article did not eto be thoroughly scientific based, particularly with respect to summer month characteristics compared to those of winter months.

http://www.nytimes.com/2008/03/09/automobiles/09MOTO.html?_r=1

There was a post on this a little while back - with some interesting points… have a nose around. :smiley:

I had nitrogen in my busa tyres once just cuz it was offered free of charge with a pair of tyres, makes no difference what so ever under ‘normal’ road use. Well not that I noticed:)

Is Nitrogen explosive ?

Would bring definition to the term … Blow Out … :slight_smile:

As the air that we breathe is 68% nitrogen we should hope not :slight_smile:
I may try this in the summer as i use o.f.n ( oxygen free nitrogen ) in my work, as we have 3 bikers in the household may even try and do some sort of long term test and post the results.
Anyone have any ideas of what parameters should be taken into account and how they could be evaluated/ analysed ?

nitrogen is completely inert which is why they use it. it does absolutely nothing except take up space.

the new Nissan GTR has nitrogen filled tyres, but really, if we’ve not reached the limits of air filled tyres, would we feel any benefit from Nitrogen?

its nots as if I daily think, “oh my tyre could be expanding more evenly as it heats up”:stuck_out_tongue:

It is not so much that Nitrogen is inert (it isn’t really when compared to Noble gas Argon, Xenon, etc). Main benefit is a homogeneous environment, you only have one variable for expansion and behaviour.

Compared to air, the major difference will be the lack of moisture.

Not completely inert, if it was we wouldn’t be here (no DNA, RNA, amino acids etc.), but it is near as damn it :P:D:hehe:.

To be honest I doubt you would notice it much, so long as you keep your tyres properly inflated, air is 70% nitrogen any way.

Jebus, are you guys Boffins or some thing ?

Im feeling very thick now :slight_smile: :slight_smile:

No just a sad toss pot with a Degree in Engineering now working in computers.

Oops Kevsta, didn’t see your post.

I’m just a sado with a degree in Genetics.

I feel like I’m in a science class.

Q: How many quantum physicists does it take to change a lightbulb ?
A: One. Two to do it, and one to renormalise the wave function.
(Explanation - Renormalising the wave function is something that has to
be done to a lot of quantum physics calculations to stop the answer being
infinity and makes the answer always come out as one.)

Get it? I don’t!

Let’s talk about breasts. :hehe::w00t:

Massive great big ones or pert perfectly formed ones. :smiley:

All of the above - I’d just have fun testing them!

Starting with weighing them… Whe heyyyyy :w00t::hehe::w00t:

The problem with quantum physics and with most branches of physics they are still not sure what the rules are. What works on a planetary scale ceases to work at the microscopic. And don’t even get me start on the forces.

As for boobies, as long as there natural with no hint of saline or silicone i love 'em.

Hooray For Boobies, is the title of an album by the Bloodhound Gang.:smiley:

See what you started:):wink:

Great! I for one would be very interested in your findings. Here are some suggestions for parameters to consider:-

Start the test with a set brand new rear and front tyresTake note of tyre pressure at least three times a week. Ideally sunday morning, wednesday evening and saturday after last ride.Take note of ambient temp during pressure readings Take note of each time you had to refill the tyres with gas (nitrogen or air) and possibly by how muchIt would probably help to note the actual low and high temp for day of each ride so that you can plot the temperarture variations against recorded pressure lose.For this to make any sense, obviously you would need to compare your findings with a bike using air filled tyres. Possibly also fitted with brand new tyres and having a near similar ride pattern. Note that the bikes used in the test only have to cover the same mileage, not necessarily the same exact time of ride.The graphs ploted should tell you which gas requires more frequent fill up.Also note the milleage at which the tyres were replaced. Which should indicate which gas is more efficient.Good luck, if l think of anything else that might be usefull l shall post it in due course. [Time to take the crazy professor gear off, it s pub time]

I wonder how they go about filling a tyre with nitrogen. Do they suck out all the air in the tyre first before filling with nitrogen? Or possibly just fill the tyre with pure nitrogen upon the ambient pressure of air already in the tyre?

Somehow, l don’t think they could really fill the tyre with pure nitrogen completely. There would certainly be residues of air and the obvious inert gases like helium etc. So the benefit is a reduced volume of oxygen and moisture in the tyre really. Thus not perfectly homogeneous.

The benefit being a reduction in moisture and an increased homogeneous pressure characteristics i.e better tire wear and slower pressure lose. This is still better than full on air l think.

Good point, not sure what is normally done but i will put a vacuum pump on the tyres first.Am replacing both tyres on the zephyr in a couple of weeks time so will do it then .

Just thinking aloud here so don’t shoot me;)

As one of the secrets to a good handling bike is reduced unsprung weight (ie wheels, brakes and tyres)

I wonder if anyone’s tried putting helium in bike tyres?:w00t: