I did a search and nothing really came up so I was hoping someone could shed some light on this. I've heard somewhere that once you go synthetic you can't go back to conventional, is that true? I have Amsoil full synthetic in my bike right now, but I'd like to start doing my own oil changes with conventional. I only put on about 4000km per season and change it prior to every season. I don't think I need synthetic for that kind of riding. What do you guys think? Thanks!