Echo J7: Cycle Computer Manual |link|

Place the wireless transmitter on the front fork. For best signal strength, keep it within 1 to 2 feet (60cm) of the head unit.

Includes a backlight for low-light visibility, an alarm, a stopwatch, and a scan mode that cycles through metrics automatically. echo j7 cycle computer manual

Find your tire size (e.g., 700x23C) on the sidewall and look up the corresponding four-digit circumference code (e.g., 2096) in the standard tire size chart . Place the wireless transmitter on the front fork