I took the engine out earlier to check things over and the clutch is trashed. The Bell has a nice groove in it and the shoes are worn. Not sure why sometimes it would stall and sometimes it would not. I figured if the clutch was bad it will stall all the time but it did seem to get worse. I think maybe It was a combination of plug being too cold and clutch wear. It ran great last weekend with no problems at all then this weekend the stalling came up.