Originally Posted by
Crank57
As a tire gets hot or cool the water vapor in the air makes the pressure fluctuate much more than nitrogen or dry air would.
Bike tires don't get nearly as hot as race car tires. Therein lies the reason that N2 in bike tires isn't that great of an idea.
Also, CO2 liquifies at a much higher temperature than any other easily attainable and safe gas, justifying its use in cartridges.