I have stuttering motor, its as if it not getting enough power. Iv tested it with a meter and all seems fine and on a visual inspection there seems nothing wrong with it ??.
Is there any other test I could do ??, its a xing 1404 5500kv.
It’s either the motor, esc, fc or a loose connection.
Best bet is by elimination. Firstly:
Swap the motor with the one next to it and see what happens. Does the fault stay where it is? Or does it move with the motor.
1 Like
job for tomorrow 
Could be the firmware on the esc. There is a problem with the latest BLHELI firmware causing motors to stutter and esc’s burn up when Bidirectional Dshot is activated. Try deactivating Bidirectional Dshot to see if it makes a difference
1 Like
It’s not affecting all esc’s but it is affecting my SpeedyBee V2. That’s how I heard about it
Iv had an idea of setting up my old AIO board as a test rig. Would that be possible or would I need a vista as to connect to the controller…
. But analogue still
If I’m testing via Betaflight motor tab I wouldn’t need the visa 
Good idea. That Darwin fpv aio board with a single dead esc now has a purpose.
I’m just preempting that I may have to replace the motor, and was thinking of changing them all for a different make…
I have 1404 5500Kv and was looking at some like these as this isn’t the first time iv had to replace a Xing motor on my whoops…
But is a 4500Kv going to make much difference opposed to my 5500Kv…?
I’m sure you have 4200kv Nick
Is it stuttering throughout the whole throttle range, or just when idling?
If it’s throughout the whole throttle range then this is indicative of one of the three phases feeding the motor has failed. This can be due to:
A broken wire from the ESC to the motor.
A poor solder connection, again between the ESC and the motor.
One of the three outputs of the ESC have failed. This would most likely be due to a blown FET, and can be visually confirmed by looking for a crack or small hole in the casing of the FET.
If it’s stuttering at idle this indicates the PWM value feeding the ESC is too low. Usually calibrating the ESC’s will fix this.
This is on my whoop not the Apex
You know what they say about assumption 
lol Sorry mate my bad 
Bloody hell I hope not its a new AIO, its been flying great, had a couple of bumps while Bandoing but nothing significant.
Idid have to extend one of the wires on it as it broke but was fine after.
With it being a whoop they dont really take that much impact due to the hoop and how slow it goes… But what they do sometimes do is get sucked to the wall ceiling (if that make sense?) but its just a case of cutting the power asap…
I had to do this with my Tyro129 build as the motor wires were not long enough. However the motor wires were lacquered and I’d failed to scrape it off fully on one of the wires. This resulted in a very poor solder joint and a subsequent stuttering motor.
Well good news is its not the motor, so my Im going to re install it and see if it was a dodgy connection ?
Hope its not the AIO as ill be well pissed if it is 
Iv not long fitted it…
Dare I say, go into BLheli suite and check timing value, drop it down one level and see if that helps 
Well soldered it all back in and still the same problem, Im now starting to think its the board as when it starts up it makes the 2 tone noise.
If you turn up the volume you can hear it, Iv yet tried another motor in the that position and I do have that spare one from my build 
So think that is going to be the next port of call…
Just a thought, the spare motor I have is a lot bigger that the damaged 1 will this matter if Im only testing ???