Yeah, I understand that's the best oil, but quite a bit more than the standard Mobil 1 auto oil. So I was wondering if anyone's using the automotive oil. From the internet research I've done, automotive synthetics are better (less viscosity breakdown etc) that the best natural (dino) motorcycle oils. But it's hard to know what to believe. Seems that everyone who's tried the Mobil 1 automotive in their bikes is really happy. Apparently that brand doesn;t have some of the environmental additives that others do that can cause wet-clutch slippage. ?! I may try it next time. It's only gunna cost about $10 more than the dino-based motorcycle oil (Castrol Grand Prix) that I usually use.