Having recently come back from taking the Rotax engine service course I spent some time getting refamiliar with my own 912 ULS by taking off the exhaust pipes (putting plastic plugs in the cylinder head holes), trying to figure out all the fuel lines and where I had previously left off and having a first look at how the two air filters mount to the carburetors. Hmmm... have two lengths of hose that still need the fire sleeves installed.