The MyChron Wheel Speed Proximity Sensor (also known as the "Car" or "Phonic" sensor) is designed to be mounted to the spindle or hub carrier. A trigger wheel (not included) is required on the wheel, wheel hub, or brake rotor to pass in front of the sensor as the wheel rotates (see note on trigger wheel dimensions below).
This sensor has the 712 (four-pin metal screw-in type) connector to connect directly to the MyChron3 XG-Log data logger. All other loggers and dashes should use the AiM Wheel Speed Sensor with 719 Lead (Part No. MC-217). The front of the sensor has M10 threads for easy mounting in a bracket you supply. Cable length is 78 inches (2 meters).
Trigger wheel minimum dimensions: The teeth on the trigger wheel must be at least 5.06mm (0.19 inch) deep, 2.54mm (0.1 inch) wide, 6.35mm (0.25 inch) long, and 10.16mm (0.4 inch) apart. There are no limits on the number of teeth or the wheel diameter, but the triggers must be made of ferrous metal such as steel or cast iron. If your hub has steel wheel studs or other steel bolts that protrude from the back of the hub face, they can be used to trigger the sensor if the critical dimensions are met. The back of the sensor now features an LED which will light if the trigger is positioned appropriately.