When I did my build , I put a fast clutch kit and bill it basket in. Mine drags when I pull the clutch in, especially if it's been sitting a long time. I also have a out 10hours on the build, so the clutch still isn't broken in yet I'd assume.
That being said, is start with said above. It's either jetting and or the clutch is sticking. When you did the build did you pull the clutch? Check the basket for grooves?