I don't think that BC covers are serviceable. Contact customer service to find out for sure. Also, BC is an entry level coilover. If you are picky it is highly likely that you will not be satisfied with their performance even after a revalve. In addition, using compressed air to recharge is a terrible idea. Even if you could, it will take specialty tools to charge pretty much any coilover that you find. It's not something that most people can DIY.