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Originally posted by Maverick
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This has been proven to be false, I posted the science behind why earlier and if dry compressed air is used the "benefit" of nitrogen tyres weighing 2.5 grams less per tyre disappears. The only slight difference can come about from there being some additional moisture in the tyre if the tyre is not filled with dry compressed air but on the flipside seeing as the tyre is not removed, cleaned out and filled 100% with nitrogen I fail to see how nitrogen works any better 
"N2, being a lighter molecule, diffuses out faster. Having less weight, it also improves handling as there is less rotating mass - but not by much. If we assume a tyre has a volume of about 24 litres and is at 2.5 atmospheres pressure, then the weight of dry air in it will be 72.5 grams. (with air at 80% relative hummidity, it will be about 71 g). Fill it with N2, and it will weigh 70 grams. So you save a whopping 2.5 grams out of maybe a total tyre weight of 10 kg. Olympic cyclists fill their tyres with He to save a few grams - but then a few grams means 0.01 second which might be the difference between a medal or not.
A gram or so of ice in the tyre may cause issues, providing you drive around corners at 300 km an hour within a few seconds of starting the car and before it has melted and evaporated.
As the tyre warms up, the air or nitrogen will expand. If the tyre is at 20 C and then warms up to 40 C, then the air or nitrogen will expand by 1-((273+(40-20))/273) = 0.07 or 7%. If the tyre is at 35 psi at 20 C, it will increase to 37.5 psi at 40 C. Filling with different gases will make no difference as they all expand the same amount if raised by the same amount. If anything, using a denser gas such as S8F will take longer to heat up due to the higher specific heat (amount of heat required) to take it from 20 to 40 C (or whatever) but then will stay warmer longer."
You have consumer organisations, government organisations, motoring organisations and various magazines and so forth all debunking Nitrogen.
You have tyre stores, nitrogen sellers and people who also promote slick 50 pushing Nitrogen with wild claims.
A gram or so of ice in the tyre may cause issues, providing you drive around corners at 300 km an hour within a few seconds of starting the car and before it has melted and evaporated.
As the tyre warms up, the air or nitrogen will expand. If the tyre is at 20 C and then warms up to 40 C, then the air or nitrogen will expand by 1-((273+(40-20))/273) = 0.07 or 7%. If the tyre is at 35 psi at 20 C, it will increase to 37.5 psi at 40 C. Filling with different gases will make no difference as they all expand the same amount if raised by the same amount. If anything, using a denser gas such as S8F will take longer to heat up due to the higher specific heat (amount of heat required) to take it from 20 to 40 C (or whatever) but then will stay warmer longer."
You have consumer organisations, government organisations, motoring organisations and various magazines and so forth all debunking Nitrogen.
You have tyre stores, nitrogen sellers and people who also promote slick 50 pushing Nitrogen with wild claims.
Each to their own but I'll stick with science and back the former group
[/QUOTE]As I say, when I checked the pressure differences between hot and cold for nitrogen fill and normal compressed air fill, the nitrogen fill did not alter pressures by as much. Generally, my findings were that the nitrogen was about 2psi lower difference to that of normal compressed air. Same general outside hot/cold air temp, same tyres, same car, same original starting pressure of the tyre.
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