To use only the buddypress profile cover image please follow these steps :
1. Deactivate the bp profile cover plugin .
2. Now please goto appearance -> theme -> editor -> select modern theme to edit .
3. find the init.php file to edit and then find the ” #buddypress .course_header div#item-header ”
then remove the “!important” as shown in screenshot : http://prntscr.com/a56bw1