Might I suggest you go to Whiteblaze.net and talk to them about it. The backpackers will talk your ears off about it. You will need to tell specific temp ranges you are considering. Time of year? do you sleep cold or warm? male or female? Elevation of camp sites? Type of tent? feeding and hydration habits. Many of them know a lot. Friendly non-judgement folks. They might try to get you to sell your bicycle and buy trail shoes and a good pack.