What is a “normal” amount of crankcase puke?

In the process of changing the air filter, I found about 1/2” of oil in the bottom of the air box.  Pulled the puke plug and I’d say about 4oz flowed out.  Bike has 6500 miles and I’m guessing the puke plug has never been pulled and puke drained.

Cleaned up the bottom of the air box with some paper towels and brake parts cleaner.  

I’ll be watching it going forward, but what is “normal”?  Would a large amount indicate the oil may have been overfilled sometime in the past?  Other causes of excessive puking?

I know some folks have catch cans installed after deleting the air box.  How much puke do you catch in your puke can?

More puke if you do much riding over 75mph

I check my catch can at every oil change (3500-mile intervals).  It always has about one tablespoon.

Hey Versy, are you running a Hayden KrankVent or did you fabricate something with an umbrella valve?  I always liked my KrankVent, but when I figured out that I was chewing up main bearings I took the KrankVent off just to be sure it wasn't inhibiting the oil drainage from the exhaust valve spring pocket.  I have just about 20K on the setup now and haven't had any problems with metal chips on the drain plug.  Do you ever see any chips on your drain plug?  I want to reinstall the KrankVent and I would feel a bit more comfy if I hear that you are running the check valve with no evidence of bearing failure.