Need help, shculze 18.97/lehner cogging...

[T-Bro]

I had to put my shculze 18.97 in my tc3 buggy (lehner 4200, external bec) since I shipped my mgm for updates, and it does some serious cogging before it will start to move. Once it decided to finally start moving it performs like you wouldn't believe. It didn't do this running my Bigmaxximum at all. I hit the gas and it moved! The only difference with the setup is I used a receiver pack plugged into my receiver instead of an external bec. What do you think is the problem?