Hi y'all!  Well I've come up with a bit of a head scratcher.  I'm in the process of converting an old Ace Aerocommander Shrike to electric and while the build went fairly smooth, I've run into a configuration issue when it comes to running the twin motors.  Both motors ( Aerowind 2210/25), ESCs (Aerowind 18A), and batteries (1100mah, 3C) came from Brodak.  Individually each functions as designed however when the ESC's are coupled together via a "Y' cable to the receiver the problem arises.

When I plug the “Y” cable into the throttle port for the receiver both motors will spin up but at slightly different speeds (especially noticeable at lowest throttle settings).  As a check, I can unplug one battery and both motors will still run but again at noticeably different speeds.  Whichever motor attached to the ESC with the battery appears to be the dominant motor through out the throttle range.  Both motors seem to run at comparable speeds when the other motor and ESC are removed from the “Y” cable.  My problem is ensuring both motors run at the same speeds throughout the throttle range, max thru low to off and that is not what I’m seeing at the moment.

I would certainly appreciate any insights or suggestions  .

Hi Jim,

That sounds strange. Did you calibrate the throttle range for each esc? This is done by sticking the throttle stick to full throttle and plugging in the battery. You get 2 quick beeps and then you bring back the throttle stick to low throttle. That should help. If you have a tach then see what the difference is and post it here please. Hope this helps!

Keith R

Assuming your speed controls have built in BEC circuits, try disabling one BEC by removing the positive pin from one of the ESC connectors. Use the tip of an Xacto knife to lift up the little plastic retaining clip, and pull out the pin. The positive is in the middle. Cover the exposed pin with heat shrink so it doesn't short to anything. Alternately, you could remove (or even cut) the positive wire on one leg of the Y harness where one of the ESC's plug in. Having potentially slightly different BEC voltages both feeding into the Y-harness can make the ESC's unhappy, in my experience.


Just out of curiosity, are you simply plugging one lipo into each ESC, or are you paralleling the packs and feeding both ESC's the same power?

Hi Bill!  Thanks for your response.  Honestly, I'm a bit hesitant to do this modification.  I'm really a bit uncomfortable, although I don't doubt it may work.  As for the configuration, yes the ESC's have their own BEC built in.  There is one motor and one battery per ESC and the ESC's control cables are connected via "Y" cable to the throttle input of the receiver.  Actually, I thought it was the simplest configuration possible.

It is a simple and reversible procedure as long as you don't cut any wires. Something else you could try, assuming your radio is sophisticated enough, is plug one of the two ESC's into an aux. channel, and mix throttle to aux. on the transmitter. This would isolate the two speed controls by putting them on two separate channels in the RX.

Okay!  Kool!  I can do this as I'm using a Spektrum Dx-7.