Multiple cameras, multiple mounts and multiple shoots. I would discourage shooting anything that requires your hand to operate your camera while riding, as it will reduce your ability to control your bike and risk your own security.
I currently own two cameras, but can check out GoPros from the schools where I teach. Check to see if your camera has a helmet mount accessory, for the top, side or front/jaw of our helmet. My favorite mount is a suction cup mount as it allows me to place the camera(s) on the windshield facing the rider, or outward aimed down the road. I can also place it on side panels and the front fairing as well for low angle, frontal and rear shots. Chest and wrist mounts are also possible. I once placed my suction mount on my helmet visor (I wouldn't encourage it as I was practically riding blind).
I've shot the same route a few times, at the same time of day with a different camera angle for good B-roll coverage. Recently I got my second camera and placed a mounting adhesive on my right mirror for a good 3/4 shots of the rider (me), over my dashboard shots, down the road shots, or shots facing the right side of my bike.
My next vlog will include a set of four camera angles while I'm riding interspersed with drone and time-lapse footage of the city I'm riding in. The real trick with more than one camera (if they're different brands) is to match the exposure and color quality, or keeping the continuity consistent if the footage was shot on different days, or under different traffic and weather conditions.
- Wuf