on a 50-mi ride? bananers. PB&J sandwiches. home-made trail mix. Honestly, whatever sounds good that you can work with. If you're bonking, then the nutrition is (more?) important earlier in the ride. Good preride meals that work for me include oatmeal with a little almond milk, walnuts, honey, and blueberries (that combo is off the top of my head, you can make it however you'd like). What are you eating pre-ride now?