okay so this is probably a dumb question but ive been flying for about a year and this is the first time ive tried cleaning the motors on my freestyle build. used compressed air and a tiny bit of isopropyl on a cotton swab to get some dirt out of the bell housing. put everything back together and now motor 3 has this noticeable vibration at anything above like 30% throttle, sounds almost like a tiny rock is in there but its not, i checked.

betaflight blackbox is showing more noise on that motor channel too compared to before. the prop is balanced and ive swapped it with another one i know is fine, same thing. im wondering if maybe i got moisture in the windings somehow even though i let it dry for like an hour, or if i somehow knocked one of the magnets loose which i didnt think was possible. its a 2306 2450kv motor if that matters, pretty generic brand.

could be a bent shaft honestly. super easy to do when youre handling the motor, even just setting it down wrong on a hard surface. pull the prop off and just spin the bell by hand slowly, if you feel any grinding or the shaft looks even slightly off center when its spinning thats probably your answer. generic 2306 motors are like $12-15 so might just be replacement time depending on how beat up it already is.

yeah seconding the bent shaft thing, ive done this more times than i want to admit. also though ? when you put the bell back on did you make sure the circlip or retaining pin seated properly? if the bell isnt fully seated itll wobble and create exactly that kind of vibration pattern. i had this for like two weeks before i figured it out, felt so stupid. just pop the bell off again and look at it carefully before assuming the worst.

also one hour might not be enough dry time if you used more than a tiny bit of iso, some people say overnight to be safe but ive never actually had moisture cause this kind of symptom so idk, probably not that.