If you just put in a new clutch and it doesn't work properly, I'd tend to want to blame the clutch. It is likely just mis-adjusted and won't disengage all the way while the bike is running.
Have you adjusted it properly? As in, does the arrow on the cluch arm match up with the mark on the engine case when the clutch just starts to grab? If not, you'll need to pull the clutch cover off and adjust it internally.