I did a search but couldn't find anything on this. I have carried CO2 while mountain biking for a few years now and recently purchased a 10lb tank for my FJ (thanks TRDparts4u:bigthumb. Before I switched to tubless (amazing difference for you mountain bikers) I would need to fill up my tire with a compressor shortly after getting back from the trail if I had a flat and used the CO2 to refill. Is this normal? I haven't used it with the FJ yet but I am curious. Basically, does CO2 lose pressure and need to be refilled faster than regular air? Thanks!