Fenris, I agree with what has mostly been said above. If you overfill your oil level by too much, if it's just a smidgen, it's no big deal, you can leave it. But if you have overfilled by several millimetres it's worth draining it out by some means as this increases the crankcase operating pressure and can lead to leaking engine oil seals. The engine breather won't cope if there's a lot more oil than there should be and won't cope with the pressure. The engine is unlikely to burn off any appreciable amount. You can if you wish just slacken the drain plug and carefully let a small amount drain out. This means almost completely undoing the plug with a gloved hand. When you reseal it, do it up enough to stop the main flow of oil, then with a clean lint free cloth wipe the threads of the plug and the mating surfaces where the plug sits, then just nip it up lightly. Don't torque it too much with very wet threads, you may strip them. Nipping them up is fine, take it for a short ride then just re-tention the bolt slightly, wipe it again, and just ride it. You will find it won't leak. But do keep a check on it for a few days.
