This is the unit I use on all of our bikes (trike)
https://www.planetbike.com/store/pro...-computer.html
I have one mounted on my Catrike Expedition, wired to a sensor on the front left wheel. Works flawlessly and it is guaranteed for life. Very easy to set up. I change the battery every year; just record the odometer reading before you remove the battery, and during set-up enter the odometer reading and start again. Hope this helps. Mike