Is Nitrogen Better than Air in Car Tyres?
Air is 78 percent nitrogen, just under 21 percent oxygen, and the rest is water vapor, CO2 and small concentrations of noble gases such as neon and argon. We can ignore the other gases. There are several compelling reasons to use pure nitrogen in tires:-
1) Nitrogen is less likely to migrate through tire rubber than is oxygen,which means that your tire pressures will remain more stable over the long term.
Racers figured out pretty quickly that tires filled with nitrogen rather than air also exhibit less pressure change with temperature swings. That means more consistent inflation pressures during a race as the tires heat up. And when you're tweaking a race car's handling with half-psi changes, that's important.