So I threw some air shocks on my quad today, and they picked the stance up pretty damn nicely. The front is a little stiff, but I'll adjust them eventually...but the rear one seems to be too soft. I've cranked the collars down as far as they would go, but it needs to be stiffer. Could I take it to a shop and just have them add more nitrogen, or do I need to do something else?

 

If the shock is rebuildable, then it sounds like freshening it up will help you out. Adding a stiffer spring may also be in order. Many shops can handle a rebuild, I even see private individuals advertising this service locally. Depending on the machine and intended use, for a bit more you could get it custom valve by one of the specialty suspension shops also.

 

The shocks are just cheap ones off of eBay, and I highly doubt they can be rebuilt. Can I take them somewhere to have nitro added? It's just a set on my 125.