Quote Originally Posted by Chadd View Post
Unless I am mistaken this is the home feedrates from the config file.

#define HOMING_FEEDRATE {50*60, 50*60, 4*60, 0}

that is the X, Y, Z, extruder rates, in that order.

There are at least a few threads on the reprap.org forums about this.
What is the origin of that config file? Is it a stock Marlin configuration.h from the Zalm repository, or the configuration.h that the manufacturer (MakerFarm) provides to be used?

It is correct that the Z motors on the i3v printers can't be reliably driven to 4mm/sec. I found even 3 to be borderline in my testing.