Motors My Madness, Need Some Help

[stevelewendon]

hey guys, just a bit of background, been off work and stuck at home sue to covid 19 and ll that, decided to see if i could maybe build a beast of some sorts, iv taken a old touring car and mounted a motor in the front to drive the front wheels and a motor at the rear to drive the rear wheels, not after watching a you tube video from rc help.com of how to wire up twin motors and esc with either one or two battery's i thought how hard could this be so did what i needed to do used some cheap motors sensorless motors and cheap esc, i did not want to kill my good stuff, both motors and esc are the same, came out my two boys off road buggys, wired it all up set up receiver and transmitter, switched it all on and sort of worked, i cant understand why it wont work that way i picture it, so we have two battery, two esc two motors, the only common thing is the receiver, the motors and esc have own power source and on paper it should work but what is happening is i accelerate and i get hesitation and no speed at ti,es if a feather the throttle i can get both to work but there is no real throttle response unless i do it very slowly, thrash it on the acceleration and nothing happens, what is going on any one got any ideas, maybe a second receiver, can that be done will it fix the issue WHAT CANI DO TO MAKE THIS WORK. cheers guys

 

[Tony]

You can only use one Rx for this setup. Two Rx's will cause way more issues than it will solve.

One thing to remember in a setup like this, the motors need to be spinning exactly the same RPM otherwise you will get under/overdrive on the axles. When I made that video, I was thinking airplanes where a slight variation in speed is not that big of a deal. You can trim that out.

So start with the following.

You only need one BEC. If you are using the BEC from both of the ESC's, then pull and secure one of the red wires going from the ESC into the Rx. There could be a voltage battle going on which can burn stuff up.

Next, calibrate both motors/esc's at the same time. Since they are sensorless, close is about the best you can do with this setup.

Make sure your throttle curve in your Tx is setup correctly. Linear is where I would start.

And finally, make sure your batteries are both at the same voltage (full charge). This is yet another variation that is going to damage gears on the car and may cause instability when driving it.