It got much worse as the temperature of the engine bay increased. It ended up being an air pocket in the clutch lines. As the lines heat up, the air expands and raises the clutch engagement point. It will eventually cause a slight clutch engagement resulting in slippage. I bled the clutch a bunch and it didnt change. I finally got a vacuum pump and bled it from both bleed points. Only took 15 minutes with the pump. Bingo, now its perfect. Search this site for clutch bleeding. It can cause a myriad of problems, and is fairly common. Make sure that it's fully bled , then adjust the freeplay on the clutch rod. Keep in mind that the adjustment in the clutch rod is primarily intended for freeplay, and not to set the clutch engagement point. Hope this helps.
