Not a very good idea if you want that motor to survive.. Would be no problem on a decent path, but if you are humping a motor through dense brush, you won't get very far...
Mike and I did a horrible portage a few years ago, I humped that little 4 stroke of his by the handle like carrying a suit case.. Not the best, but if I had to drop it, it was only going 1-2ft as most.
The Sportspal was even more fun!! But the 10lb+ walleyes we caught were well worth it!