AiM MyChron3 Basic - Manual (Page 16)

16
Installing the RPM clip
The RPM sensor clips directly on the spark plug wire. While running the RPM
cable along the chassis between the MyChron 3 display unit and the spark plug
wire, the RPM cable should be positioned as far as possible from the
thermocouple wire, to prevent interference.
It is suggested to use cable ties to securely attach the RPM cable along the
chassis to prevent damage.