[Closed] Fatbike fine-tuning

I’ve been riding the Fatbike for a couple of months now, getting used to the handling over various types of terrain. The Husker Du tyres I’ve recently fitted seem to match it really well and it feels very capable over most surfaces. Dirt, gravel, small rocks are easily rolled over. However, I’ve been having some problems descending over rockier tracks. The problem is that the little “suspension” there is derives from the tyres themselves, running at somewhere between 8 and 12psi. While it will take a couple of boulders in its stride, things start to get out of control a little when the rebound of the tyre starts making the bike (especially the front end) too lively.

Of course, there isn’t really any way to control/damp this rebound....
.... or so I thought.

What I sussed out is that I could improve the performance of the “suspension” by using a different, more dense gas. With the help of a car-mad mate, I managed to fill the tyres with some Nitrous Oxide. What a difference this has made. The tyres deform less over rocky terrain and thus I get less rebound from them. This has got me to thinking – what other relatively available gases would it be worth trying??