Again, if you go with the grade that bike manufacturer suggest and just make sure it's a good make you should be fine. If they suggest mineral or semi synth, go with that. Going to fully synth can cause clutch slip on some bikes if it's not designed for it. Castrol, Motul, Silkolene, etc are quality brands. I'm using Castrol GPS in the CBR which seems fine and use Motorex in the Aprilia.