a 2 hour 18 mph bike ride is about how many calories burned anyway? 7-800?
true though, the better food is for you, generally lets you eat a lot more of it!
if you are having a problem eating enough calories, you need to densify your calories. some dietitians recommendations are for up to 20-30 percent of your diet from fat. I think upping your healthy, moderate cheesburger intake can easily remedy the calorie shortage you are facing.
I've been on winter expeditions where we required and rationed out 5,000 calories per person per day. To force down that many calories, we were forced to gnaw on sticks of frozen butter. Literally, we ate frozen butter off the stick.