Both Mobil 1 and Valvoline make bike specific synthetics that they say are specifically for wet clutches. I think the terminology you want to stay away from is "energy conserving" which can be found in the round oil certification on the back of most automotive oils. This is supposed to indicate that 'friction modifiers' have been added to the oil, causing clutch problems. The only one I have found that seems to be usable, other than the Mobil and Val, is Shell Rotella T6. It is a diesel synthetic that also 'says' it is compatible with the JASO MA certification. Although it does not actually display that certification. Just put some T6 in my bike tonight. Will see how it does over the long haul. Others on the forums seem to like it.