Figured it out.
You can set the firmware max speed with an M code.
Thrue experimenting I found the TAZ can handle these max speeds without stalling the motors:
X axis: 11,500 mm/min (192 mm/sec)
Y axis: 12,500 mm/min (208 mm/sec)
Z axis: 250 mm/min (4 mm/sec)
Then just send the following command to the firmware:
M203 X192 Y208 Z4
and now the machine will never move faster than those settings, even if the g-code or printer host software commands it to. Now it appears these settings do not store in permanent memory, even after trying M500 to store the settings, when it was powered down and back up, the settings were not there.
So, I have put that M203 command in the “custom G-code” area of slicer so that it always sets the max speed…now i should be able to turn up the max speed in slicer, and it should be able to move very fast in non-print moves, without stalling any of the axis’s.
More explanations here: https://forum.lulzbot.com/t/left-z-axis-motor-spins-the-down-at-the-beginning-of-a-print/115/9