I only run air, but I make sure to ask for metric air.
After a few months of topping up the tires as the pressure drops, I find I'm running 98% metric nitrogen because all the smaller molecules are the ones that leak out, leaving behind the big fat nitrogen ones.
'03 GL1800A | Porsche 968 | Ford F-150 | Skidoo GSX (2) | Seadoo GTI (2) | Suzuki ATV (2)
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