if i have nitrogen in the tires, can i adjust pressure with normal compressed air?

if not, can i just let all of the nitrogen out and refill with normal comressed air...

 

1) You can add regular air back in the tire with no issues. Just keep in mind when you add regular air you are diluting the nitrogen bringing the percentage of nitrogen down in the tire.

2) Yes this is the usual way we do it, just make sure you get as much nitrogen out of the tires as possible.

hope this helps!

 

Air is already nearly 80% nitrogen, so I wouldn't worry too much about it.