Brand New Builder - Prop spinning strangely


New member
Hi, I am a brand new RC plane builder and trying to put together the FT Tiny Trainer with the Graupner mz-10 transmitter and Graupner GR-12L receiver. It all came in the FT Tiny Trainer kit that I purchased from

Here is a video of my issue:

I am very aware that I could have plugged in something incorrectly but I haven't been able to find documentation that shows how to do it properly with this setup. I have the motor plugged into channel 1 on the receiver and it looks like the wireless connection is good. What's weird is when I push the throttle instead of getting a smooth prop spin I get strange jerking motions from the prop that doesn't look normal. I've tried many different combinations but no luck. I've combed through the forums looking for any insight on this but I haven't found anything yet. My apologies if there's an obvious answer that I missed while looking.


Construire Voler S'écraser Répéter
Make sure the bullet connectors between the motor and ESC are plugged in well and there aren't any gaps to allow arching between the wires.


What is this motor doing? Video may help!

Ok I shot a quick video showing what might be happening, hope it helps you out.



Got Lobstah?
Site Moderator
Good video ViperTech. You beat me to it. I actually have my wing which is stuttering and I was going to video the troubleshooting process. I still might since there is an actual problem and I can show how to discover where (which phase) it is.


New member
Whoa, thank you so much!

Wow, that's super helpful! Sorry for the late reply! I've tried replacing the ESC with a new one and the same thing happens. I'll be trying your suggestion of checking the connectors on the motor. Thank you!

Hill Top Flyer

New member
Stuttering problem

Try plugging the ESC three-wire control lead (with the JR type plug) in to the receiver's throttle channel. The ESC will power the receiver from that channel and the throttle signal will run the ESC for motor control. Hope this helps.

I have 'cooked' a few ESC's from crashing and they will stutter (lost phase) when damaged, too.


New member
Bad Motor?

I checked the connections on the motor leads and they looked soldered properly. I ended up buying a new ESC and motor to determine if either of the parts are bad and the new motor works great. I guess I had a bad motor? Hoping that Flite Test will be able to send a replacement so I can repurpose it into a future setup.

Thank you everybody for your help!