Its worth reading up on the philosophy and technique of ultra-light camping at
http://www.monmouth.com/~mconnick/

For cyclists, its important to consider your repair kit, which can get heavy. You need enough to get you out of trouble, but does every rider in your group need a headset spanner?
On a longer ride, you have to face the possibility of an on-the-road divorce from your travelling partners, so you need more self-reliance, but for a weeks tour, it pays to combine your kit.