I think not. It's a neat win, though.
There are a couple of kinds of clean, and yours doesn't quite fit any of them.
-If you make the goal and the red piece and all the construction pieces fall off the edge, I call that 'Clean'. Your red piece doesn't go too, so it's not regular clean. I think it would if it weren't for that bump on the left side.
-If you make the goal and all the construction pieces fall off the edge, and the red piece stays in the goal, I call that a 'Clean Champion'. (Based on other terminology on the forum. You could also have Clean & Green, Clean Boomerangs, Clean & Green Boomerang Champions...) DaCoTa seemed to want Clean Champions when he opened this thread. Your red piece doesn't stay in the box, so it's not a champion. Since there seems to be no friction on this piece, it just goes to the bump and maybe comes back all the way to the right. (I'm guessing- yours is the slowest one I've seen, and I've only run it an hour. Maybe it stays at the bump.)
-Then there are those who want it really clean. sccooks http://FantasticContraption.com/?designId=262204
from this thread is Super Clean, and my http://fantasticcontraption.com/?designId=265147
based on that is a Super Clean Champion. You still left a boulder in the goal. Mine http://FantasticContraption.com/?designId=281581
gets four of the seven boulders, but still isn't technically clean or a clean champ.