40-50miles? wow. How fast do you go?
re: eating. This is a motivation thing, not an energy thing, right? If you're low on energy and can't push yourself any faster, then maybe your body doesn't have enough fuel. What distances are you riding? If you're riding for more than a couple of hours at a time, you *should* eat something during the ride. If you're talking about shorter rides (for me, under 40-50 miles is usually ok), then there really isn't much need to eat during the ride, but you should make sure you've eaten enough before you go out.