I wouldn't worry about it.

Give the backing plate a wipe over with a rag.

Check your oil level with the dipstick.

 Vent your crankcase breathers to atmosphere!...........most of that oil is getting sucked back into your combustion chambers and building carbon up in your cylinders!

Burto.

I agree..... vent your crankcase to the atmosphere or even better to one of those small crankcase breather filters mounted somewhere on the bike/frame.

Just a thought, harley put the breathers into the inlet dispite the emissions,don't make sense realy,,, oil = pollution. You'd think they would vent to the atmosphere??????

Dunno ! check the dip stick.I keep mine 2 notches above the add mark when cold works ok.Try a different brand of oil.

Have you had the oil pump out lately i found that if it is not put back in line it will through oil out the breather, but if not lower your oil level and if you like to ride hard it will leak,they don't all do it just some.

The bolts that hold the backing plate should have "o" rings on them. Replace them all.That should fix the problem