Up or down Simon? I have the rears around 28-29psi to try and get a little more grip.......... Don't get me wrong, it is not that bad at all, it does get a little though. <{POST_SNAPBACK}> Good question, I get a bit of axle tramp with ~ 36PSI in the rears <{POST_SNAPBACK}> One would think lower the pressures because if your getting a bit of axel tramp at 36PSIand F6 rapid is still getting a tiny bit of axel tramp at 29PSI it needs to come down just a little bit more, say 25 PSI. Also I cant see the tyre pressures going over 40 PSI that's just too much.