I'm paleo also and have no issue with energy levels during rides. Get a copy of Friel's book, Paleo Diet for Athletes. Yes, all you high carb folks, Friel believes in Paleo eating for cyclists and runners. Also, do a google search for "train low, race high" which entails training low carb and then racing high carb. There are a lot of serious endurance athletes that eat paleo without issues that use that formula for training and racing. It just takes a while for your body to adapt to burn fat and not carbs, so stick with it and it will get better. Expect at least a month to get acclimated - that is with cycling, not just eating paleo.