re: Nitrogen in tires?

yes but nitrogen is a dry gas, oxygen carries humidity which expands when heated...
and they aren't the same, i think its a 1.4kj difference which isn't much but pure oxygen is better then nitrogen with heat, but then you are still paying for someone to compress it properly (and im not talking about a simple air compressor) which costs more than nitrogen but leaks through the tire faster so your still at a loss.
Nitrogen is better, its really just a conversation about how much gain do you get for how much you have to pay.