I was using a new line of servo called Align 620 digital ultra speed....the servo works fine...the reciever works fine...the Tekin esc works great now...but put them all together an u have cogging...i changed it out for a hitec high torque..car works fine now!!! if u have cogging check out the servo..it might work just fine but it sends a signal to the motor an reciever that makes the problem....at lease was my problem..
