Has an NBA game ever ended 86-80?
It has. 86-80 has been a NBA final 26 times in 77,318 games. The first was New York Knicks beat Boston Celtics on December 19, 1950; the latest was Charlotte Bobcats beat Cleveland Cavaliers on November 15, 2013.
That makes 86-80 the 846th most common final score out of 3,189 that have ever occurred in NBA. One point away, 87-80 has happened 38 times and 86-81 has happened 32 times. Nearly all of its occurrences fall between 1980 and 2009.