These docs are for an old release.
View the v7 docs
defaultEventMinutes 1.4
Determines the length (in minutes) an event appears to be when it has an unspecified end date.
Integer, default: 120
By default, if an Event Object as no end, it will appear to be 2 hours.
This option only affects events that appear in the agenda slots, meaning they have allDay set to true.