TYRE MONITOR

A tire monitor includes a sensor device arranged to detect an operating parameter of a tire and a protective housing for the device, the device being retained on a ring having spaced end portions , the ring being resiliently radially biased. The provision of a retaining ring facilitates installation of the tire monitor within a tire assembly, so that the sensor device can directly monitor the operating parameter of the tire. The protective housing protects the sensor device from impact, vibration and temperature extremes.