So I have a bunch of old smart phones ( androids mostly) and I was seeing guys use them as gps and speedos. Though it was pretty cool so I did some research and found out it was dam easy. Old stuff but here’s a link: https://www.instructables.com/id/Ultimate-Bike-Computer-From-an-Old-Smartphone/
It’s kinda lacks at acceleration but once up to speed your good. Looks cool too
If anyone knows how to set a temp guage or rpm gauge on the phone, please share!
Will sell smartphones if interested* lol