this has been bugging me for weeks now. one of my motors ? front right on a 3.5inch toothpick build ? will just cut out for a split second during hover or slow flight. not a full stop, more like a stutter or a hiccup. the quad dips slightly then recovers. happens maybe once every few minutes, not consistent, totally random.

ive already ruled out the obvious stuff. props are balanced and secure, tried two different sets. soldering on the ESC looked fine under magnification but i reflowed it anyway just in case. motor screws tight. the motor itself spins freely by hand, no grinding, no cogging that i can feel.

ran motor tests in betaflight and it looks fine on the bench, smooth ramp up and down. but in the air it does the thing. im starting to wonder if its a signal issue or maybe the motor is actually going and it just doesnt show up on the bench test. anyone seen this before

check your motor wire connections right at the motor bell where they exit. on smaller builds especially those tiny wire leads can have a partial break in the insulation or a strand thats almost but not quite broken, looks totally fine visually and passes bench tests but under vibration in flight the connection intermittently opens. wiggle the wires while running a motor test in betaflight and see if you can reproduce it. if the motor stutters when you flex the wires thats your answer.

had something weirdly similar on a 2.5inch cinewhoop a while back. turned out to be a cold solder joint on the ESC pad that wasnt visible just looking at it. only found it because i poked around with a probe while it was running on the bench and found the joint flexing. not saying thats definitely your issue but reflowing and actually looking isnt the same as load testing, bench test with the props on and let it run at like 20-30% throttle for a few minutes while watching the motor in the OSD if you have rpm logging enabled, might catch something that the static test misses.

also what ESC are you running, some of the cheaper all-in-ones have had issues with specific motor outputs being flaky under load. just curious