Hooking tachometer up on 2007 1100 spirit

[Jim C]

I have a wiring diagram but I can't tell for sure what colors the wires are supposed to be on the coil. My diagram is clear enough to follow the wires but the wire markings are not clear enough for me to be positive what the actual markings are. I am wanting to hook up a tachometer that I got for X-mas. It has the single fire adapter and it says to hook up one wire to the negative side of each coil. I just want to make sure which wires that would be so I don't ruin the tach. I have tried to search for the answer without much luck.

Thank you,
Jim C

[rocksolid]

You should be Dual Fire. Here is a tutorial on tach installation. It may help you. (If you wire both coils, it will read double.)
http://www.eurekaboy.com/shadow/tach.htm

[Jim C]

Thank you for the link and help.

Jim C

[rocksolid]

The bike is SINGLE FIRE. I mistakenly said earlier that the bike is dual fire. Sorry about that.

We have a Dual Plug - Single Fire System. Both plugs in the cylinder under compression fire together. Only one cylinder fires at a time.

http://www.mpsracing.com/products/Dyna/ig01aj.htm
What is the difference between Single Fire and Dual Fire? What are the benefits?

A. Dual fire ignition systems fire both spark plugs from a single coil at the same time. The majority of the spark energy goes to the cylinder under compression while a small portion goes to the cylinder on the exhaust stroke causing a small wasted spark. Single fire ignitions separate the firing pulses, only firing the cylinder under compression. The main advantage of dual fire systems is simplicity and low cost. The advantage of single fire systems are smoother engine operation and the elimination of the popping that sometimes occurs when long duration camshafts are used. There is no horsepower advantage with single fire ignition systems.

The power connections (one is usually red) go to a circuit that is hot with the key on. I used power from the running lights in the headlight bucket. Black is to ground. The green signal wire goes to the cold side of the coil (with the key on) I believe it is a blue wire with a yellow stripe. I made up the y-connector as shown in the tutorial, for this connection. That should be it.

My hardest part was mounting the tach. on the bar.
I used a rubber mount to minimize effects of vibration.

[Jim C]

I just wanted to update my status. I hooked up the tach with the single fire adapter and that didn't work very good. So I hooked it up to just one coil like you did and it works great. Thanks for all the good advice and the documentation with pictures to follow along. The only change I made was to buy a spade fitting from Radio Shack that has a female fitting with two male fittings so I could hook up both wires right off the coil. I got a package of eight for $1.99, catalog number 64-3064. The tach I have is supposed to be for a dual fire so that is why I tried the the adapter.
I also put a 12V power point in that is hooked up to the battery directly. I have an inline 10 amp fuse that I put under the side cover by the battery for easy access. The power point is mounted in the plate between the tank and forks like someone else had done.

Jim C