Quote:
Originally posted by racer14itc@Nov 8 2005, 06:09 PM
However, even if you use nitrogen, you have to use some sort of vacuum pump to evacuate the moisture laden air out of the tire first, otherwise you'll still have moisture in the nitrogen/air mix in the tire. If you just pull the valve stems and let all the air out at atmospheric pressure (14.7 psi), when you refill to 30 psi in the tire (44.7 psi atmospheric), you'll end up with a 1/3 - 2/3 mixture of air and nitrogen. (PV=nRT)
Makes sense, most people, if one doesn't want to vacuum the old air out, one can get to a better percentage of nitrogen by going to atmospheric, filling and repeating once more. Then you end up with a 90% nitrogen fillled tires... for all intensive purposes that's pretty good.