September 21, 2005 When we first saw the N2Revolution PR frenzy, we were disappointed that the hype focuses so much on the downside of poorly inflated tyres (which don’t need nitrogen to remedy the situation) and not so much on the actual benefits of the system. Launched in Florida last week, the company’s flagship tyre inflation solution, the PurigeN98, uses 98% nitrogen to inflate tyres instead of air (78% nitrogen, 20% oxygen), and the basic idea is that if everyone used nitrogen instead of air in their car tyres, the world would be a cleaner, better place, with less petrol, oil and tyre consumption and hence less pollution. That’s true and the more we looked into it, the more using nitrogen makes sense. But will it save anybody any money?
Anybody who has ever had anything to do with Motorsport knows what a difference a few pounds per square inch (psi) can make to tyre temperatures, wear, performance and the amount of time it takes to complete a given distance. Logically, if it makes such a difference over your average 10 lap car club dash, it can make a lot more difference over the life of a tyre on the road, … and it does.
Every car/tyre combination has an optimum range for tyre inflation pressures and according to the US Federal Department of Transportation, roughly 80% of all vehicles in the United States have under-inflated tyres. Indeed, the vast majority of vehicle owners do not know what their optimum tyre inflation figure is, so it follows that the vast majority of the cars on the road have incorrect tyre pressures. The actual figures are scarey – given how many of us die on the roads, we’re still negligent in critical safety precautions such as ensuring our tyres can safely transport us, our children and our friends and that we can safely control a lump of metal weighing a ton or more travelling at speed amongst our extended family.
Now through valve leakage and seepage, tyres inflated with air drop roughly 2 psi per month – so it’s not a set and forget thing. If you don’t actively maintain your tyres at the optimum pressures, they will eventually deflate and you’ll pay in many ways.
Incorrectly inflated tires are the leading cause of tyre failure and can adversely affect braking, handling and steering – that makes sense – no matter how good the car is, it is only as good as the tyres which transmit its motive forces to the tarmac.
As a rough rule of thumb, if your tyres are 20% below the optimum, you’ll reduce your tyre life by up to 50% and the additional rolling resistance can add 10% or more to your fuel consumption. Across the life of a tyre, that’s a massive financial penalty on the driver and it’s no wonder that the U.S. Department of Energy reports that the national US fleet burns 4 million gallons of gasoline unnecessarily every day due to low tire pressure.
So how will filling your tyres with nitrogen make any difference?
Firstly, nitrogen does not leak from tyres as readily as air. There are many factors involved in this but bottom line is that it will retain its pressure much better and without oxygen in the mix, won’t expand as much when heat is added, maintaining the optimum tyre pressure and tyre temperature far better.
That’s why nitrogen is used in by Formula One and NASCAR teams, in heavy-duty commercial off road equipment and by commercial and military aircraft. When you’re landing an airplane or hitting the apex of a racetrack turn at 200mph, it’s nice to know your tyres are correctly inflated.
Secondly, oxygen is corrosive. It reacts with the rims in tubeless wheels (the vast majority), whether they’re made of steel or aluminium, and this results in a fine powder of rust or aluminium oxide inside the tyre which also jams in the valve seat every time you check your tyre pressures – which further degrades the entire system and adds to the pressure seepage.
Thirdly, the N2Revolution system is purpose designed to overcome all these problems. Apart from taking the oxygen out of the air used to inflate your tyres, it also removes the moisture. Water and oxygen and heat combined significantly increase oxidation of the wheel rims an accelerate the aforementioned build-up of powder in the tyres. Most service stations give their air away free and hence pay no attention to maintaining their compressed air systems correctly, so that’s where the moisture will come from.
Changing over to nitrogen
Obviously, the best time to change is when you’re putting on all new tyres to avoid as much of the contamination of the system as possible. You should also give the inside of the rims a thorough clean.
Maintaining the system is also likely to be a problem as Nitroflators are not exactly all that common and topping up a tyre with air from a gas station will require you to purge the tyre and start all over again, or simply accept that it was all too hard to begin with and revert to an air-based inflation system.
Indeed, you’ll also need to carry your own tyre gauge from the point you convert to nitrogen as using the gas station tyre gauge is out of bounds too.
One of Gizmag’s writers spent many years testing cars and motorcycles for leading magazines and reports always carrying a tyre pressure gauge to ensure pressures were correct – he swears there is a vast discrepancy between gas station pressure gauges and their accuracy. Indeed, we know of one leading motorcycle journalist who broke a collarbone falling off a bike to find that he had over-inflated the tyres 15psi due to a faulty gauge at a service station.
The Return on Investment
Using nitrogen in your tyres will increase the life of your tyres, and it will help to ensure your tyres maintain their correct pressures due to less seepage, at least in the initial stages. We foresee a problem in maintaining the correct pressures in the longer term simply due to the scarcity of Nitroflators.
So be aware that it will involve a LOT more time and effort to do something that is almost certainly habit if you already care about maintaining proper tyre pressures i.e. checking the pressures every time you fill with gas and maintaining them correctly.
N2Revolution tells us that Purigen98 dealers are providing the nitrogen inflation service for a variety of prices. Some dealers give it away for free, and others charge US$29.99 per passenger car and add an additional US$10.00 for larger trucks and SUVs.
Now US$7.50 per tyre is very steep – it’s unlikely that it will return enough increased tyre life to repay that sort of investment. And if the seepage of pressure was ever really an issue for someone who maintains their tyres correctly, it will add the unholy complication of knowing your tyres aren’t at optiumum pressure and not being able to do anything about it.
N2Revolution is investing heavily in promoting nitrogen use to the market, and is engaging in talks with other nitrogen providers toward educating the market and promoting the use of nitrogen. If it succeeds, and Nitroflators become commonplace at service stations, one of the major hurdles to using nitrogen in tyres will have been overcome and we suspect that auto enthusiasts everywhere would swap at that point.
Indeed, the general problem of the populations ignorance to correctly maintained tyres is likely to see Tyre Pressure Monitoring Systems (TPMS) become commonplace in vehicles over the next decade as relying on human knowledge and nature isn’t working.
Specialist tyre retailers and gas stations are being sold the system as an added income stream – a new way of either creating a point of difference in their service (giving it away) or up-selling their customers (charging).
It is a better system but we suspect that the ROI on paying US$7.50 a tyre would be a big fat negative – that is, it’s an investment that won’t return a dividend.
You don’t need nitrogen to ensure your tyres are correctly inflated. Optimum tyre inflation using plain old air will give you optimum fuel efficiency, dramatically reduce your tyre wear and prolong the life of your tyres. Indeed, the type of person who’s prepared to pay $7.50 per tyre for nitrogen isn’t going to be looking for the last 20% of life from their car tyres anyway.
We like the idea of using nitrogen in tyres. In mission critical systems (racing, aeronautics etc) it makes perfect sense because the extra few dollars is meaningless compared with the cost of failure, or in th4e case of racing, lack of competitiveness. In industrial systems where every minute of life needs to be extracted from a tyre (mines, agricultural etc), there is an irrefutable case for using nitrogen because there is a professional maintenance system in place to ensure the other parameters in the equation are all optimized too.
But for car tyres for everyday use, we’re not convinced, and we strongly disagree with the founder of the N2Revolution who said at the launch, "While we are aware that we have a superior product, our most important mission is to promote the use of nitrogen as perhaps the single most important factor in proper vehicle maintenance."
You don't need to be a Rhodes scholar to know that the above claim is not true.
The press release from the company also reads: “He added that since most people do not keep their tyres inflated at optimal levels, a primary cause of accidents and fuel inefficiency, drivers will begin to reap the gas saving benefits of this technology and recover the cost of nitrogen inflation several times over within a very short period of time.”
We strongly suspect that is incorrect too, though we’re happy to share the sums with our audience if anyone can provide us with a set of figures to prove the above statement.
It is sad that the claims of this new company have overstepped the mark because the basic principle of using nitrogen instead of air to inflate our car tyres is a good one.
