Motor stuttering

Akivaa

New member
Hello, I recently bought a speed build kit for the mighty mini, tiny trainer, along with the power pack a. I built the plane just fine and I have all of the servos hooked up correct but the main motor seems to be having an issue. When the prop is not on the motor, the motor spins fine mostly but stutters some. When the prop is on the motor it always stutters. I’m not really sure what do do about this. Is the ESC bad or something? The connection from the motor to the ESC is fine so I know it isn’t a break in the connection. This is my first plane and I don’t have much RC car experience at all so it would be great if you could help.
 

Headbang

Master member
It is motor or esc, I am leaning to the motor tho. Check to make sure no mounting screws are possibly touching the windings inside the motor. Other then that not a lot to do without a spare esc or motor to test. Of course someone else may come up with something I am just not thinking of.
 

Merv

Site Moderator
Staff member
Could be a bad solder joint, try giving all of the bullet connector a slight tug. Could also be a timing issue with the ESC. Look at the documentation for the ESC to change the timing.
 

BS projects inc.

Elite member
Chances are it's the threads on the motor. If you used the long screws you screwed into the motor threads and the motor will stutter now with any sort of load on it. Simply put it's the wiring on the motors in my opinion. Idk though, like merv mentioned it could also be the esc timing, I don't have too much knowledge on that subject so ask around.
 

Akivaa

New member
It is motor or esc, I am leaning to the motor tho. Check to make sure no mounting screws are possibly touching the windings inside the motor. Other then that not a lot to do without a spare esc or motor to test. Of course someone else may come up with something I am just not thinking of.
I switched to the smallest screws to hold the motor in place but I haven’t seen any improvements.
 

Akivaa

New member
Could be a bad solder joint, try giving all of the bullet connector a slight tug. Could also be a timing issue with the ESC. Look at the documentation for the ESC to change the timing.
The bullet connectors are not soldered in place for the motor the the ESC. I’m not entirely sure what you mean by changing the ESC timing but I try to look more into that. Thanks
 

FDS

Elite member
How is the motor connected to the ESC? Pictures might help people see what’s wrong. Did you solder the connectors or were they already fixed to the motor and ESC when you got them? Make sure no metal is visible on the bullet connectors when plugged in, as if they touch and short out they will destroy the ESC.
If the powerpack came from the FT store contact their Customer Services as well.
 

Akivaa

New member

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Brianna81

Active member

Looks like the connector on the right is not fully pushed in. A loose bullet connector can cause a bad connection and not pass current through it properly. Might double check and really push them in to make sure they're fully seated. You don't solder the bullet connectors together though, they just push in and should be tight. You shouldn't be able to very easily pull the connectors apart. I've had some I thought I was going to tear the wire out of the motor, despite being careful not to put any pressure on the motor side, before I would get the bullet connector apart.
 

Akivaa

New member
Looks like the connector on the right is not fully pushed in. A loose bullet connector can cause a bad connection and not pass current through it properly. Might double check and really push them in to make sure they're fully seated. You don't solder the bullet connectors together though, they just push in and should be tight. You shouldn't be able to very easily pull the connectors apart. I've had some I thought I was going to tear the wire out of the motor, despite being careful not to put any pressure on the motor side, before I would get the bullet connector apart.
Ok, thanks. I’ll try pushing them in more, although I’m pretty sure that is as far as they will go for me.
 

Brianna81

Active member
Ok, thanks. I’ll try pushing them in more, although I’m pretty sure that is as far as they will go for me.
From my experience, when a bullet connector is fully seated, there shouldn't be any "shiny" showing. If there is, as close as the wires are to each other, they could touch causing a short to occur. So this could be part of your issue as well. Hopefully there wasn't a short created that damaged something, that now can't be fixed. Though since that is a power pack from FT, they should be setup correctly so that the bullet connectors are fully covered, and shouldn't show the shiny part as mentioned above when connected properly
 
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Akivaa

New member
From my experience, when a bullet connector is fully seated, there shouldn't be any "shiny" showing. If there is, as close as the wires are to each other, they could touch causing a short to occur. So this could be part of your issue as well. Hopefully there wasn't a short created that damaged something, that now can't be fixed. Though since that is a power pack from FT, they should be setup correctly so that the bullet connectors are fully covered, and shouldn't show the shiny part as mentioned above when connected properly
Ok, I’m not at home right now so I’ll try pushing them in when I get home. After that if problems still occur what would you recommend?
 

Merv

Site Moderator
Staff member
The bullet connectors are not soldered in place for the motor the the ESC. I’m not entirely sure what you mean by changing the ESC timing but I try to look more into that. Thanks
It looks like the bullet connectors are solder to the wires. Give then a tug to see if you have a bad solder joint. Any break in any of the 3 wires could cause stuttering..
Some ESC allow you to change the timing, no idea if your is one of them.
 

FDS

Elite member
Wrap some Etape over the shiny bits of connector, that will stop them shorting. You should calibrate the ESC as well, have you done that?
Again, if it’s from the FT store or a reputable retailer, contact their CS.
 

Akivaa

New member
Wrap some Etape over the shiny bits of connector, that will stop them shorting. You should calibrate the ESC as well, have you done that?
Again, if it’s from the FT store or a reputable retailer, contact their CS.
Ok, thanks. I have already calibrated the ESC and I sent a email to FT about it and they said they would get back to me. I’ll try wrapping the wire with electrical tape, haven’t done that yet.
 

cranialrectosis

Faster than a speeding face plant!
Mentor
Most often stuttery motors are caused by a loose connection between the ESC and the motor.

Poor (cold) solder joints or bullets that can short out by touching another bullet or wire are prime suspects.

Too long of mounting screws are also common.

NEVER push a stuttery motor. Throttle down and check the connections.

If you are running really high power 2205 motors you may need to adjust the timing on your ESCs, but this is FAR more rare.

9 out of 10 times stuttery motors are caused by a loose solder joint between the motor and the ESC. I would focus your attentions there and test with a smokestopper.

 
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Bricks

Master member
I have had bad ESC`s do this exact same thing with no prop on motor runs great put prop on motors stutters and will not run. If you can try a different ESC is the easiest test.
 

Wildthing

Legendary member
If you have an extra esc and even motor you can swap and do the process of elimination to find the culprit.

I have had where cold solders even though not loose were just bad , stripped the shrink wrap off and re soldered the connectors and then worked perfect.
 

Akivaa

New member
If you have an extra esc and even motor you can swap and do the process of elimination to find the culprit.

I have had where cold solders even though not loose were just bad , stripped the shrink wrap off and re soldered the connectors and then worked perfect.
Ok, I don’t have an extra ESC but I’ll look at the solder joints to make sure that they are connected.