I guessing its the belt i haven't torn in to it yet to see if it's something else. What would be wrong with the sheave. I put an machined one on it about 500 miles ago along with a heavier spring and the slider upgrade from unleashed. The only upgrades done to it besides the clutch is an MSD, Two Brothers Duals, intake, bored TB, and 14" wheels with 26" terracrosses. I was going to throw the cam and piston I have for it on this week but now the thing has troubles movin.
Two Btothers Duals
26" Terra Crosses on 14"