Make sure your throttle and brake epa's are 100 percent when setting up your radio to your esc. LRP speedo's dont like the epa's to be above 100 percent, why the mfg's make a percentage to go to 150, i dont know the reasoning there. Possibly a bad motor sensor or the tiny sensor wire pins are not pushed in all the way. I use a scribe and carefully push the tiny pins in untill they seat all the way.