I kind of disagree with Marko there, with all the bearing toys it really matter how you keep your bearings. I'll suggest you all to clean the bearings like yoyo-dudes and dudettes do and remove the thick greasy thing that pretends to be kind of shady lubricant and use proper low viscosity oil instead. Your diabolo will be much more silent (well, to be honest have a different sound on it), and the diabolo will spin much longer. The draw back here is that you need to start acting like those yoyo-dappers and launderettes and keep washing your bearing and oiling them all the time. Like taking care of your baby, which it, without a question, is.