Originally Posted by brianappleby
I think the concept of using nitrogen isn't about choosing an ideal gas, but more about eliminating water vapor in the air.
That might make sense. Air is 70% nitrogen to start with. Helium is what you want for light + nonreactive. You'd have to fill your tubes up every 30 miles, probably.
LBS guy was talking about using latex tubes (more porous) and nitrogen (smaller molecule than, well, the other 30% of what's in air), so definite recipe for constant topping off of tires in exchange for supreme weight weeniness. But really, if N2, why not He?