This Adjustable Handlebar Mount is designed to be clamped onto any round material (or semi-round) pipe, tube or bar. It is easily moved and is perfect for your ActionCamera and great also for any full-sized camcorder. It comes in two sizes, 1) For tube diameters from 2cm to 2.75cm and 2) For tube diameters from 3cm to 5cm.
As this is a purpose built mount it is acceptable for trackdays. The 8mm thread will fit into any camera with the standard thread on the bottom of the camera which means that you can use a standard camera with this also.