We all know the issues that these cup starters can give and I used to avoid messing with them for that reason. I built a Utility for my grandson a while back because I had a full crank with a G4 carb on it. All good but then the cup starter went into the usual "I am not going to grab" mode. I pulled the cup off and with a 14 inch half round bastard file, flat face facing my left, I filed a series of slots in the cup about every 10mm. These slots are not deep more like deep scratches, probably 1/2mm deep at the most, problem solved works like a dream, catching every time now
