so ive been dealing with this for about two weeks now and its driving me insane. one of my rear motors on my 5inch freestyle build starts twitching/stuttering when i punch the throttle past maybe 40%. like it doesnt desync exactly, it just kind of hesitates and then catches up. the other three motors are totally smooth.

ive already tried reflashing the ESC (its a 4in1 aikon AK32 35A), recalibrated, checked the motor screws, even swapped props thinking maybe a blade was nicked. same behavior. i also checked for any obvious cold solder joints on the motor pads but everything looks clean to me. the motor itself is a T-Motor F40 Pro IV 2306 and it was running fine for like 6 months before this started.

at this point im wondering if the motor windings are just starting to go or if its more likely the ESC channel is dying. has anyone had a specific channel on a 4in1 just start flaking out like this? i dont really want to replace the whole ESC if its actually the motor.

had almost the exact same thing on a hobbywing xrotor 4in1 a while back. swapped the motor to a known good one first before anything else ? if the twitching follows the motor to a different ESC pad then yeah its the motor, if it stays on that pad its the ESC channel. takes like 20 mins to rule it out and saves you a lot of guessing. in my case it was the ESC channel slowly dying, probably heat related over time.

also worth checking if there's any play in the motor shaft. sometimes bearings start to go and it causes weird behavior under load that doesnt always show up on a bench test.

might be worth running motor debug in betaflight and looking at the RPM telemetry if your ESC supports bidirectional dshot. you can sometimes see exactly when and how bad the dropout is. not saying it'll fix it but at least you'd know for sure which component is lying to you lol