A friend has just returned from a holiday down under,and said that thay are filling tyers with gas instead of air to get better mph is this true.
regards
john (light ace gxl)

- (#9044) john, 10 Jun 03 14:28

see previous thread john..tyre pressures,your question answered by australian tyre company
- (#9045) ron coe, 10 Jun 03 14:46

I wonder if the gas is "inert" and not subject to changes in volume when the temperature rises? With my experiments to try and improve the front suspension, I have experimented with a range of tyre pressures and notice that well known phenomenon ie,a considerable increase in pressure when the tyre is hot, ie, after a long run. I can't see that an increase in MPH can be achieved with a gas but, you learn something new every day (especially on this indispensible forum)

- (#9046) John Davis, 10 Jun 03 14:53

Indeed Ron is right, the explanation in the previous thread is good. I.e. when you inflate with air, you get all the gasses that are in the atmosphere compressed into your tyre. The most notable is the fact you get moisture (inherent in the air) which is the major cause of pressure changes inside the tyre due to increased heat. The heat comes from friction with the road surface, which causes the gasses to expand. The advantage of using oxygen free nitrogen is that it contains no moisture, I'm also lead to believe that Nitrogen has one of the biggest molecular structures in the make up of ait & therefore does not 'leak' through the rubber as readily. Oddity is that some racing teams experimented with helium filled tyre (Actually reduces effective weight of car) but they too found that the gas leaks through the rubber too easily.
Many of our local tyre supplires are no offering OFN as an alternative to air at an extra cost.
Regards Rob.

- (#9047) Rob Drinkwater, 10 Jun 03 15:25