I have OVER 3000 miles on my engine on Opti-2 alone. I read PAGES on how this stuff works and when i rip apart my engine, all i see is pretty shiny metal and almost no carbon on my piston and i run 35 to 40 mph on my bike almost everyday. I love this stuff and will never use any other oil... Period. The only problem that I have, (which is not because of the oil) is whenever the motor gets hot, it tends to autocombust. This is not huge problem. Just means that i need to choke it to kill it. But i live in Louisiana and its 108 degrees and this oil works like a charm. I was skeptical at first and it has only done good for me.