Oil in air box

SOURCE: 2006 Yamaha TTR 50E pouring oil out of air cleaner housing

With the oil problem I read on another site that Yamaha did that so that excess oil would be burned up in normal running (but this was usually smaller amounts). Anyways they disconnected the tube going to the air cleaner and had tied up in such a way that any excess oil would land on the chain thus lubricating it. But if you have that much oil coming out it could be that you have put in too much.