The Service manual calls for 4.3 quarts but if you do that there is an overfill problem so only put 4 quarts in. Make REAL SURE that you get oil for "V-Twin Motorcycles" even if it is synthetic. There are two plug one in the front in the crank case and the other in the right side below the side cove under the oil tank. Don't bother using the dip stick to check it never reads the same two time in a row and if you top it off you can over full it real easy. When filling put two quarts in the dipstick tube then crank the bike up for about 15 -20 seconds but make sure you dip stick is in and tight or you will get a oil bath.
Then put the other two quarts in and put the dip stick in. If it isn't smoking or leaking oil then it doesn't need the oil check until the next oil change and just do the 4 quart thing again. Oil changes run from 3000 miles with regular oil to 5000 miles with synthetic oil. AGAIN make sue it is V-Twin Motorcycle oil for wet clutches as the engine oil also bathes the clutch plates. I sent you something in a message. BTW
I was station at Bentwater/Woodbridge air bases near Ipswitch for 3 1/2 years.