Transitioning to electric tachometer

[Guest]

Hey guys. So my gauges have had some problems for a while and I'm either going to repair them or replace them. I've been looking at tachometers like this one http://www.amazon.com/Vktech-Univers...cle+tachometer or this one http://www.ebay.com/itm/12000RPM-LCD...4ba76b&vxp=mtr

I once installed a Trail Tech Vapor on one of my bikes and I loved it. You could just wrap a wire around one of the spark plug wires and it'd produce a signal that the vapor could read. Does anyone know if the same approach could be used with any tachometer that was expecting a square wave or am I going to have to go with the Vapor if I chose to replace my cluster?

[posplayr]

RPM pickup can be a bit tricky, with some devices being better than others. There is a recent thread here where JohnKat installed a Koso and had issues going from coil primary and the factory suggested using an electronic IGN pickup.

http://www.thegsresources.com/_forum/showthread.php?228128-Koso-Tachometer-speedometer-on-GS-1000&highlight=

The more traditional way to condition the coil(-) wire is using a zener diode with resistor for current limiting.