> Quick, someone do the math: after inflating a tire to, say, 40 psi by
> adding nitrogen atop regular air at atmospheric pressure, what's our % N?
>

Roughly 93%

>> On 10/17/2015 02:57 PM, Max Wellhouse wrote:
>> Eric:  I have a friend here in Cedar Falls Iowa that fills his tires
>> exclusively with nitrogen.  He runs a really small tire mounting and
>> balancing shop out of his garage and does mobile repairs as well.  He
>> says that in order to mount tires and fill them with nitrogen, you
>> have to make sure the bead sealing surface is absolutely pristine, so
>> there's no chance of micro leaks from pitted sealing surfaces.  I
>> think he charged like $10/tire to do the fill.  Not sure how he would
>> evacuate the normal atmospheric air form the process, but I have used
>> his services on my Vanco II Continentals mounted on Mercedes CLK
>> forged aluminum rims(mounted on my 90 GL  BTW)  and they haven't lost
>> 1 psi in like 4 years.  I think Tire Rack offers the service as well.
>> NASCAR Racers use nitrogen     YMMV