If you own a Harley Davidson, you know how important it is to keep your bike in good condition. One of the crucial components that you should never overlook is your ignition system. This system requires regular maintenance to ensure that it functions correctly. One aspect of this system that many Harley owners struggle with is the wiring of the single fire coil. In this article, we will explore the Harley single fire coil wiring diagram, explain how it works, and provide some helpful tips to make the wiring process a breeze.
What is a Single Fire Coil?
A single fire coil is an ignition system component that is designed to fire each spark plug independently. This means that each spark plug will only ignite when it is supposed to, preventing overlapping or misfiring. The single fire coil is found on Harley Davidson motorcycles that were built after 1984. It replaced the dual fire coil, which fired both spark plugs at the same time, and was less efficient.
How Does a Single Fire Coil Work?
The Harley single fire coil works by firing a spark plug at the precise moment it is needed. This is accomplished through a series of electrical signals sent to the coil from the ignition system. When the coil receives a signal, it generates a high-voltage spark that ignites the fuel in the cylinder. Unlike the dual fire coil, which fires both spark plugs at the same time, the single fire coil only fires one spark plug at a time, ensuring the correct timing and preventing misfires.
Why is Proper Wiring Important?
Proper wiring of the single fire coil is essential to ensure that it functions correctly. Incorrect wiring can cause issues such as misfiring, poor ignition timing, and even damage to the coil. Some Harley owners may be hesitant to tackle this task on their own, as it can be intimidating. However, with the right information and some basic tools, wiring the single fire coil is a manageable task that any Harley owner can do.
Wiring the Single Fire Coil
To properly wire the single fire coil on your Harley, you will need a few tools and some basic knowledge of how the ignition system works. Here is a step-by-step guide to help you through the process:
Step 1: Disconnect the Battery
Before you begin working on your ignition system, it is essential to disconnect the battery to prevent any electrical shock or damage to your motorcycle’s electrical system. Make sure to remove the negative cable from the battery before proceeding.
Step 2: Remove the Old Coil
Once the battery is disconnected, you can remove the old coil from your Harley. To do this, you will need to locate the coil, which is typically found near the front of the engine, and remove any mounting screws or bolts. Once the coil is loose, you can disconnect any wires that are attached to it.
Step 3: Mount the New Coil
Once you have removed the old coil, you can mount the new single fire coil in its place. Make sure to align the mounting holes and use the same screws or bolts that were used to secure the old coil. Tighten the screws or bolts snugly, but be sure not to overtighten them, as this can damage the new coil.
Step 4: Connect the Wires
The most critical part of wiring the single fire coil is connecting the wires correctly. Be sure to follow the wiring diagram provided by the manufacturer carefully. The wires should be connected as follows:
| Wire | Connection Point |
|---|---|
| Red Wire | Positive Terminal of the Battery |
| Green Wire | Ignition Control Module |
| Black Wire | Ground |
Step 5: Test the System
After you have connected the wires, it is essential to test the ignition system to ensure that it is working correctly. To do this, reconnect the battery and turn the key to the “on” position. You should hear a humming sound from the coil, indicating that it is receiving power. If you don’t hear anything, or if you hear a clicking sound, there may be an issue with the wiring.
FAQ
Q: What is the difference between a single fire coil and a dual fire coil?
A: A single fire coil fires each spark plug independently, while a dual fire coil fires both spark plugs at the same time. The single fire coil is more efficient and provides better ignition timing.
Q: Can I install a single fire coil on an older Harley that came with a dual fire coil?
A: Yes, you can install a single fire coil on an older Harley that originally came with a dual fire coil. However, you may need to modify the wiring to ensure that it is set up correctly.
Q: How often should I replace my ignition system components?
A: It is recommended that you replace your ignition system components, including the coil, spark plugs, and wires, every 10,000 to 20,000 miles.
Q: What are the signs of a failing ignition coil?
A: The signs of a failing ignition coil include misfiring, difficulty starting the engine, and a loss of power or acceleration.
Q: Can I wire the single fire coil myself, or should I take it to a mechanic?
A: With the right information and some basic tools, wiring the single fire coil is a manageable task that any Harley owner can do. However, if you are unsure or uncomfortable with performing this task, it is always best to consult a professional mechanic.
