285's or 265's? and which is the best for the money

[canuckelhead]

What I thought too, but just checking. Thanks Brandon, looking forward to the change. The nitrogen is interesting.

[mechelement]

Brandon, it doesn't appear your front tires have a bulge at the bottom like mine do. I was asking because your tires don't appear to bulge. The ballooning is understandable.

[mechelement]

Originally Posted by bdrummonds

If it makes any difference I am running 65PSI of Nitrogen in my tires. Air is good, but the oxygen molecules are actually small enough to seep through the pores in the rubber of your tires, thus the reason you have to check and adjust your pressure every few thousand miles. Nitrogen is a larger molecule and is to big to seep though the pores of the rubber. I had Nitrogen put in my tires when the were new, and over two years have not lost any pressure. I have my tires rotated, balanced, and the pressure checked every 5k miles.

Ideal Gas Law: PV = nRT; P = pressure; V = volume; n = amount of substance in # of moles; R = ideal gas constant; T = temperature. Thus, when T drops, the pressure in your tires drop (volume stays the same) even when you run pure nitrogen.

Race cars use nitrogen in their tires because they calculate the pressure increase more exactly when the tires warm up and so that when the car wrecks and explodes, the nitrogen won't act as fuel for the fire, not because the oxygen leaks through the rubber. Nitrogen leaks through rubber too, just at a slower rate.

I thought running nitrogen in my tires sounded like a good idea until my professor went on a rant about it in my thermodynamics class. LOL. It's not worth the $5.00 fee every time you fill with Nitrogen, especially when you have your own air compressor.