I have a ROC412 1800KV and an RX8 gen1 ESC. At low throttle it is really smooth. At about 20% throttle I start to get intermittent ratcheting. It will rev up to full speed but you can still hear the ratcheting a little. It is the same with the sensor wire plugged in or unplugged. I'm running it on 4S and the timing on the ESC is set to #1. I just pulled the ESC out of my Tekno to put in another car. The ESC was working great in the Tekno so I'm 90% sure the problem I'm having is with the ROC. The ROC motor is out of an old SCX10 and was working good when I last used it but the rig has been sitting for the last 3 years.
I looked at the lights on the ESC for the sensor checker. They are really hard to see but I think only two are lighting up. I was going to order a new PCB from Tower but they don't carry the TT2613. They only have the TT2513 for the Pro4 motors. Will that work?