I use helium because it makes my bike lighter, thusly faster! Nitrous is good too. If you get bored, you can huff your tires.............LOL

 

yeah i started using hydrogen the other day. it blows the competition away.

 

im constantly letting air out of my tires and adding more because of parking lot stunting and so forth so filling my tires with nitrogen would probably be a horrible Idea haha anyone who runs low pressure for stunting then fills it back up for road use prob a bad idea to pay for something your gonna let out haha

 

I am not a stunter...but that is a very good point