Sportster Primary Oil Capacity. It helps to use a funnel designed for a primary case. The primary/transmission oil supply is drained by a plug at the bottom of the primary case, near the back.
Unless your bike was abused (raced), your Sportster. A grounded oil signal switch wire, faulty signal switch, damaged or improperly installed check valve and/or trouble. To change the oil, drain it, and then dump in a quart.
Everyone who owns a Sportster should have the OFFICIAL Harley Davidson Sportster service manual.
Remove the two screws that hold the primary chain inspection cover on.
But it also states that when changing oil, you do not need to drain the case, just the oil tank. I hope this helps you learn to do this yourself. Engine Oil Change, Oil Specs, Aftermarkets and Comparisons.