I used to run Nitrogen in the tires on an Alfa Romeo that I had. The real kicker was that the shop that used the nitrogen also "trued" the tires. They had what amounts to a huge lathe that the wheel and tire is mounted on, spun up to a high speed, (something like 80-100 mph if I remember correctly) and then a rotating cutter, (think of a router or dye grinder) moves acoss the tread. The idea being to cut off the high spots that have occurred. It was a hard sell convincing me to let them cut a layer of rubber off my brand new and EXPENSIVE (to me) tires. Once I finally did it I was astounded at how much smoother the ride was (at speed) and how much better the grip was. Could never say it was just the truing or the choice of tire and care with which they balanced it. I wish I could try having motorcycle tires cut that way. Would need a machine that cuts in an adjustable arc however.