You don't need to worry about that cover unless you need to turn the engine over by hand when working on it. Oil will flow into that area when it is running to help keep the stator cool. It should not be full of oil. Use your sight glass on the side of the engine to check you oil level or a dip stick if the is no sight glass. BTW, almost all bikes, the should be checked with the bike in the upright position, not leaning on the side stand. There are a couple that do, but not many.