Pour the beans onto a plate, and pick-over looking for bad beans, or stones. Place beans in bowl, cover with water by at least 2 inches, and soak overnight.
Preheat oven to 250 degrees F.
Drain beans and place in 4-quart bean pot. Add onion, dry mustard, pepper, salt, and maple syrup. Add water to cover. Cut salt pork into 1-inch pieces and place on top of beans. Bake covered, approximately 8 hours. Check each hour to see if water needs to be added. You can add more maple syrup in place of water for flavor, if desired.
Serve the beans with brown bread, franks, or ham. For breakfast, serve with eggs, bacon, and home-fries.