so i rebuilt my quad after an arm snapped on a tree strike last month. swapped the frame, re-used the motors since they all spun fine by hand and passed the usual checks. reflashed the FC, recalibrated ESCs, redid all the betaflight settings more or less from memory with a few changes. flew it yesterday and the rear motors are running noticeably hotter than the front two after just 2 or 3 packs. like uncomfortable to touch hot, the front ones are barely warm.

its not a specific motor thats the problem, its both rears consistently. which makes me think its either something in the pid tune or maybe how i routed the wires is causing some kind of interference, or maybe i messed up the motor direction? i dont know. filters are on defaults right now because i havent tuned it yet. anything obvious im missing before i start pulling things apart again

check your motor directions first thing. if one or two are spinning wrong and betaflight is compensating through the mixer it'll hammer those motors trying to correct. easy to get mixed up after a rebuild especially if you flashed and re-did things from memory. just go into the motors tab and verify each one visually before anything else.

also rpm filter ? if you're on defaults without properly configuring it for your motor/prop combo it can actually make things worse in some builds. might be worth looking at your blackbox data if you have it to see if those rear motors are just working a lot harder for some reason.

had something similar after a rebuild and it turned out one of my solder joints on the ESC pad had a cold joint so the resistance was higher on that phase wire. motor was working harder because of it basically. worth reflowing all four connections on the affected motors and seeing if that changes anything, took me way too long to figure that out