Issues with a mobula7

Hello. I recently purchased a used mobula7. It came in, everything looked great, but I decided to take it and remove the battery connectors and replace it with an xt30 connector for 2s batteries (the mobula 7 being a 2s frame I thought it would benefit from the switch as my tinyhawk 2 Freestyle did).

After a soldering and setting it up on a new 75mm frame. I tested with a quick hover, yaw left, yaw right and a bit on my pitch and roll. With that working great I moved outside.

This is where my trouble began. I took it outside, went into a hover, pitched forward a bit and moved out from in front of my house. I positioned it to the street and did a quick punch forward to test a bit of the speed.

The quad dropped. A propeller fell off. I took it inside and decided to changed all the propellers. Everything looked good. I went for another test, the back left motor was much slower than the rest.

Not really sure what to do.

Swap the back left motor with another one and see if it’s still the back left motor that is slow. If so then the esc might be on the way out. Otherwise its the motor.