I have a TPMS for sale. FOBO Bike uses tire pressure sensors mounted on the valve stems and using Bluetooth, sends the data to your smartphone. I’ve used it on my Harley Street Glide for three years and has saved me several times when I lost pressure in my tire. It’s very accurate and you can set up warnings in the app to notify in case of low or high tire pressure. It also monitors temperatures of the tires. You must have metal valve stems installed. I learned the hard way after having mine break because of the weight and centrifugal force.