I adjust the speed as well. Generally, slower speed is better for ABS. Especially, if you are having initial layer adhesion issues
3D Printer Settings for ABS
Extruder ~ 250C
Print bed ~ 100C
I am using 1mm nozzle and depending on the actual quality of the ABS, I adjust the speed as well. Generally, slower speed is better for ABS. Especially, if you are having initial layer adhesion issues