In a large bowl combine eggs, flour, onion, salt, and pepper, stirring to blend.
Using your hands, squeeze out as much liquid as you can from the potatoes.
Add the shredded potatoes to the egg mixture, mixing well.
In a large, heavy skillet, heat some of the oil over medium-high heat. Spoon the batter by quarter-cupfuls onto the hot skillet, flattening them with the back of the spoon.
Fry until the bottom of the pancakes are nicely browned - between 3-5 minutes. Flip the pancakes and cook for about 3 minutes longer.
Repeat for the remaining pancakes, adding oil to the skillet as needed. Drain on paper towels and serve immediately. Makes about 12 four-inch pancakes.