I got a deal on a friends bike he no longer could ride and has sat for years in an apartment garage uncovered. Its filthy dirty somewhat greasy, one tire low in air, dead battery and I imagine really old gas in tank. I dont know where to begin with this but wanted it as a project for myself to clean up and get it going, just dont know where to start. The obvious first I guess to either charge the battery or replace it and than I imagine figure out a way to drain the tank and lines which I never done before and not sure if i could that. I know the oil should be changed out as well. Is it ok to powerwash first and than get into it? I should mention its a 2017 with 1000k on it so its definetly worth quite a bit running. Anybody have any suggestions?