Tachometer installation question

[TheImp]

If my bike has single fire ignition coils and I install a tach without a special adapter that collects both signals, would I simply see half of the actual rpms on the tach or none at all?

I got my tach delivered but it doesn't work whatsoever and I've checked that I've attached and crimped everything properly. Perhaps I'll need the adapter.

Also if anyone knows, do I have a single or dual fire ignition coil on the vulcan 500?

Thanks.

[TheImp]

Well, I got the tach working tonight, woohoo!

Turns out my chassis ground wasn't so great and I was having a difficult time finding a good one at 11pm at night in the dark with a flashlight so I spliced in some 14 gauge to the negative terminal and voila, the tach lit up and the needle worked when I fired it up.

Its so awesome having a tach with this bike. I don't know why all cruisers don't come with them from the factory, particularly this one since it has a sportbike engine and I often need to know where I'm revving to get to the meat of my powerband. I'll edit the thread and post pics with the tach, it looks nice to me.