Review on 🚗 Allied Powersports 502100 BLU TPMS Bluetooth External Set: Excellent for Monitoring Tire Pressure (100psi, 2pc) by Anatoly Yorgason

First you have to drive over 20 km/h for them to work. One way destroys the pressure in the tires before driving. If your tires are under-inflated, you should go home and fill them up. Second, your phone must be mounted on the handlebars to see what's going on, or have Bluetooth through the speakers on the bike to hear alerts. I had tires fitted at a bike shop and they told me they would charge 42 pounds each. When I installed TPMS the same day (and finally got them working) they showed 38 pounds. My electronic pressure gauge read 39. Yes I know - only 1lb but I think they are causing an air leak and that is not exact. I "guess" you'll have to hold the valve core down to keep watching. That leads me to believe there is some kind of leak. You return to the store.