Just curious what fuel you guys are running in your xr600r's. I have an 87 that I recently rebuilt. Wiseco piston (10.5:1 I think), HOT RODS connecting rod, New Cam, Cam Chain. Recently, I bought five gallons of 108 octane from a Shell station. I noticed my bike idles faster and may pull slightly harder (It was already a torque monster). I'm not sure if I need to be running race fuel, is it a waste of money, can it hurt the engine? I have read all of the articles about how octane is really gasoline's resistance to knocking and not necessarily about relative power. So, now I want advice from you guys. Thanks in advance.