This is my first Instructable. It will teach you to how to install a secret interrupter in your motorcycle and prevent the engine to start without your knowledge.
It can be useful to prevent theft to steal your motorcycle. It works as an additional lock system.
Here in Brazil, it's very useful.
The principle is simple: The Engine need the Ignition coil work to make the Spark Plug to Work and make possible the engine to run... All we will do is to create a way to disable the Ignition coil and, by consequence, disable all the Engine.
NOTE: This instructable is available in Brazilian Portuguese in my Blog.
Step 1: Materials and Tools
You will need:
- Some Tools (The tools that come with the motorcycle can do the service well)
- 1~2 meters of double wire
- An Small Interrupter (black or other Dark color if possible)
- A Cutting Tool
- Electric Tape
Most motorcycles come with basic tools, that can be very helpful in an emergency situation. These tools can handle this job, but if you have better tools to work, use them.
The wires will be connected to the interrupter and to the Ignition coil of the Motorcycle.
The Cutting tool is necessary to cut the wires and the Electric tape to isolate them.
Step 2: Locate the Ignition Coil
The ignition coil is a part of the engine that generate electric pulses to the spark plugs. The Spark Plugs are the parts located on the engine cylinder head. They receives the electric pulse and make a little spark, and this spark makes the ignition of the engine (the explosion of the combustion into the cylinder head).
In most cases, the ignition coil is located under the fuel tank. If don't, just follow the spark plug's wire, it starts on the ignition coil. If you have doubts about the location of the ignition coil, please head the Service Manual of your motorcycle.
So, we need to remove the fuel tank and all parts that depends it. Normally you just need to remove the seat and if your motorcycle have a body kit, the body kit too.
Now you have a full view of the motorcycle engine. If it is 1 cylinder, you have only one Spark Plug... 2 Cylinder, 2 Spark Plugs, and so on... If you still have doubts about the Ignition Coil location, just follow the wire from the Spark Plug... it will end on the Ignition Coil.
Step 3: The Ignition Coil
The ignition coil is the part responsible to receive the energy from the battery and/or the engine movement, and convert it into a high voltage electric pulse, and send this pulse to the Spark Plug. This pulse is controlled by an another device, normally the CDI, but in some cases, the ECU. This control is done by a low-voltage wire, that transfer a very small pulse to the Ignition coil.
If you cut this little wire, the ignition coil will not generate the pulses to the spark plug... And it is what we want. We will put the interrupter in the wire, to close and open this circuit.
Step 4: Place the Interrupter
Now the most important step of this instructable: The Secret.
You need to find some place on your motorcycle to hide the interrupter. This place can be any place you imagine... Under the fuel tank, under the air box filter, in back of the headlight, hide in the bodykit... Any place. You must decide it carefully, because it is all the security of this system: the secret. If anyone can find this interrupter, anyone is able to start the engine, and it is very bad.
Once you decided the place, use double-faced glue tape to fix temporarily the interrupter in the place you want, and try to use the wires to reach from this place to the Ignition coil's place.
It's possible? Ok! Fine! Let's go to the next step.
It's not possible? Fine... try to think in another place to put the interrupter.
Step 5: Soldering the Wire
Now you need to soldering the wire on the interrupter and on the ignition coil.
The wire (double wire), must be soldered to the interrupter.
Now, cut the little wire of the ignition coil (make sure you have space to do a soldering in each piece of wire of the ignition coil), and solder one wire to the one wire from the ignition coil, and do the same to the other wire. You'll get some like this:
Step 6: Testing
Now the electrical installation is completed.
Turn the interrupter to the ON position and try to start the motorcycle (do now worry about the fuel tank... the motorcycle have fuel enough to run for a minute in the carburetor).
If the motorcycle starts, the installation is correct. Now turn the interrupter OFF. The motorcycle engine must stop and you will can't start if again until turn ON the interrupter again. This is the behavior we want.
If the motorcycle doesn't starts, try to change the position of the interrupter (maybe ON is OFF and OFF is ON). If it still doesn't starts, double-check the installation and all soldering points... And finally if you can't determine the problem... simply remove everything and solder the wire you just cutted. And look for someone more technically capable. :o)