so ive been dealing with this for like two weeks now and its driving me crazy. my rear left motor on my 5inch freestyle build starts twitching whenever i push throttle past maybe 40-50%. doesnt do it at lower throttle, doesnt do it on any other motor, just that one. ive already swapped the prop thinking it was a bent blade or something and that didnt change anything.

the motor itself spins fine when i test it in betaflight motor tab, like i can run it up slowly and it sounds smooth. but the moment its under actual load in the air it starts this weird oscillation and the quad wants to roll left. ive reflashed the ESC firmware thinking maybe it was a desync but honestly not sure thats the issue either because it doesnt cutout, just twitches.

motors are T-Motor F40 pro III, running a 45amp 4in1 ESC. anyone seen this before?

check your motor screws first, sounds dumb but a loose mount will do exactly that under load. had basically the same thing on a build last year and spent days reflashing stuff before i noticed one screw had vibrated half out. also worth checking if the motor bell is wobbling at all, grab it and see if theres any play. if the magnets are coming loose inside youll feel it.

if its none of that id actually look at your ESC signal wire connection for that motor output. a bad solder joint on the signal pad can cause intermittent timing issues that show up as twitching under load but test fine at low speed in the motor tab.

could also just be a bad motor phase wire connection, i had a similar thing and one of my phase wires had a hairline crack in the solder at the ESC pad. worked fine at low throttle but once current draw went up it basically lost a phase and freaked out. you can sometimes see it with a continuity check but honestly reflowing all three phase solder joints for that motor is worth doing anyway if youve already tried everything else