Potatocarl What Tricopter are you building? I have a handful of them myself. Have built and flown a TriFecta in the past, currently have two flying RCExplorer Baby Tricopters, am building a RCExplorer Mini Tri and rebuilding a recently aquired used HobbyKing Y-3.
If you provide details for what are you using for the PDB/BEC, frame, servo, etc... we can certainly try to help you out. I'm not using a Seppuku on any of my tricopters, but have them on several quads.