Originally posted by Clicker You could invest in a wide zoom and hyper-focus?
If you use a lens in the 18 - 14 mm range, you can just set it up on your chest and press the remote whenever you feel like taking a shot. While in a family reunion recently, I did just that at 16mm, (walking, not riding, but the principle is the same). After a few attempts, I am sure you could get the framing down quite well.
If you get a remote, you could even trigger the camera without taking your hands of the handlebars.