Oben BD-0 Mini Ball Head and Manfrotto 386B Nano Clamp + 1/4″ – 3/8″ work well together. They do need a male 1/4″ To 3/8″ Adapter Stud to be attached but this makes a versatile low-weight way to mount a compact camera, or Drift HD action camera, just about anywhere on a bike. And at about any angle one could want. GoPro sucks with their limited, proprietary, plastic mounting system. I might tour with a small camera next time.
Cost for the set up: about $50
Weight: 5.9oz (169g)