Apparently, there is a 2007 documentary short with this name that appears to be lost. There is not much information online about this movie other than on the film's two IMDb pages:
The description also sounds like a Joe Mama joke in the making:
Joe Ma Ma, a former outlaw biker, revisits the tough relationship he had with his own father, jail time, and the death of his two older sons, as he prepares for, and attends, a pumpkin race with his youngest boy.
There are pictures and a clip of the movie on the director's website, so we know it's a real movie, but we don't know where you can find the whole thing.