Even at 80 km races, you will still need to get in a lot of miles during the week to build your endurance. When I raced, I would eat all the carbs I could get in basically all day long, and still had BF in the single digits the entire time. Pastas, rice, potatoes, oats, milk, bananas, you name it. Avoiding all grains will be difficult if you want to get in the calories you need to sustain that level of training. You will need simple carbs to take with you on your rides - maltodextrin-type blends, and if you can tolerate eating solid food, fig newtons work suprisingly well and are inexpensive.