Thread: Nitrogen tires
View Single Post
Old 08-15-2011, 11:40 AM   #31 (permalink)
Master EcoModder
roflwaffle's Avatar
Join Date: Dec 2007
Location: Southern California
Posts: 1,490

Camryaro - '92 Toyota Camry LE V6
90 day: 31.12 mpg (US)

Red - '00 Honda Insight

Prius - '05 Toyota Prius

3 - '18 Tesla Model 3
90 day: 152.47 mpg (US)
Thanks: 349
Thanked 120 Times in 79 Posts
If the rate of leakage of oxygen is significantly greater than nitrogen then after a few fills most people will end up at 95+% nitrogen anyway provided they don't let their tires drop more than a few PSI, and if they're letting their pressure drop more than a few PSI anyway they shouldn't be worrying about what they're putting in their tires.

Note also that if you fill and top off with air, the percentage of N2 will gradually increase over time; at first you lose about half O2 and half N2, but you top off with a mixture of 78% N2 and 22% O2. So if you fill your tires with air and they initially lose about a psi a month, then after a year of this, it’s down to mostly N2 inside the tire, and the leakdown rate should slow down. For many motorcyclists, tires don’t make it through a season before replacement, so the effect is negligible; but if your car tires last four years, then by using air in them you’ve actually gotten about 3/4 of the benefit of a N2 fill, without the expense.

  Reply With Quote