I know that there have been countless threads on which oil to use, but I dont think this has been brought up. I've read that in a coulpe MXA magazines( including August 08, which includes 60 inside secrets to the 2008 yz460f) that they prefer mineral oil in this yami to make the clutch last longer. Here is the exact quote: "Even though synthetic motor oil is better for the overall package, we think that the clutch will last longer with mineral oil. The semi-synthetics and synthetics seem to shorten clutch life.Mineral oil is cheaper, so change it more often" What does everyone think about this? I am running Amsoil synthetic motorcycle 10w-40 with 6.0 hours on my 08 450, just to point that out.