ok so this has been driving me insane for the past two days. crashed last week, replaced motor 2 (front right on my build), everything looked fine on the bench ? motor spins, no grinding, all four show up in the motor test tab. but every single time i try to arm and take off it just violently flips to the right and crashes immediately. i've already reflashed betaflight thinking maybe something corrupted but same thing.

the replacement motor is the same model as the others, or at least i thought it was ? grabbed it from my parts bin and it looked identical. running 4in1 esc if that matters. starting to think maybe i got the motor direction wrong but i did reverse it in betaflight when i set it up? honestly not sure anymore i might have confused myself

yeah this is almost certainly the motor direction. when you reverse a motor in betaflight that only changes the direction it spins in the software, it doesn't change the physical rotation of the bell. the way props work you need the physical spin direction AND the prop pitch matched up correctly or you get zero thrust and the quad flips toward that corner. check which way motor 2 is supposed to spin on your specific prop layout (most standard x frames have front right as CCW) and then check which way it's actually spinning, not what betaflight thinks. easiest way is just tape a tiny piece of tape to the bell and run a short motor test to see which direction it physically goes.

also double check you actually have the right prop on that motor. i know it sounds dumb but ive absolutley put a CW prop on a CCW motor after a repair and wondered why the thing wouldnt fly straight. the little R/no-R marking on the props is easy to miss when youre rushing to get back in the air