Hello. I haven´t changed the oil yet, but from various checks on technical web-sites, I think you should use about 475ml. of SAE10 oil in each tube. If You drained the tubes totally. Be exact with the quantity right/left, as the forks need to be symmetrical. I don´t think there should be a need to put air into the forks, just atmospheric pressure as the air inside the forks compresses in use under load, when you´ve sealed them and put on the fork caps. Maybe check with a workshop or from a Haynes manual? Greetings from Norway. Øivind Amlien.