Incorporating the bike computer into the longboard – first thoughts

Ignoring the fact that the wheel mounted magnet flew of during the speed test, the actual proof in principle distance/speed measurement was a success. It’s therefore time to make the bike computer a practical and robust solution for a skateboard. At the moment everything is held on by blu-tack. But that’s not the problem since everything can be attached using glue and cable ties.

The real problem is the total height of the bike computer. The bike computer height alone is 10mm and has a further protrusion sticking out which is 5mm. This protrusion holds the battery and serves as the rail guide for sliding into the cradle. When the bike computer is docked in its cradle it sticks out approximately 20mm from the longboard top surface. There is therefore a high risk that it gets knocked off when I am carrying the longboard on the train or I may even kick it off accidentally  when jumping off the skateboard. 

The cradle part is provided by the manufacturer as a feature for the cyclist. The cyclist detaches the bike computer from the cradle when the bike is parked so it doesn't get nicked. This isn't needed on a skateboard. So ideally I can use the bike computer without the cradle. However, it’s not that simple because the cradle has two contact points that mate onto two contact points of the bike computer itself. The contact points on the cradle feed into the cable that connects the magnet sensor.

So the next step is to take apart the bike computer to see if I can bypass the cradle. My thinking is to solder wires from the magnet sensor directly onto the PCB of the bike computer. Likewise, a consideration is to remove the battery from inside the bike computer case and connect it remotely. In an ideal world all the parts could be embedded into a specially made hole on my longboard.