The 1981 Harley Davidson Sportster is a classic motorcycle that is still cherished by many riders. However, over time, the wiring of this bike can become a bit complex, making it difficult to troubleshoot any electrical issues that may arise. This guide will provide you with a detailed wiring diagram that will help you to diagnose and repair any electrical problems that you may encounter with your 1981 Harley Davidson Sportster.
Understanding the Wiring Diagram
Before we get into the details of the wiring diagram, it’s important to understand what it is and how it works. The wiring diagram is a visual representation of the electrical system of your bike. It shows the various components and how they are connected to each other. Each wire is labeled with a color and a number, making it easy to identify them.
The wiring diagram also shows the different circuits in the electrical system, including the charging circuit, ignition circuit, lighting circuit, and accessories circuit. Understanding the wiring diagram is crucial to troubleshooting any electrical issues that you may encounter with your 1981 Harley Davidson Sportster.
To make it easier for you to read and understand the wiring diagram, we’ve broken it down into different sections, each with its own subheading.
Charging Circuit
The charging circuit is responsible for keeping the battery charged while the motorcycle is running. It consists of the alternator, regulator, battery, and associated wiring. The wiring diagram for the charging circuit is as follows:
| Wire Color | Wire Number | Component Connected To |
|---|---|---|
| Yellow | 1 | Alternator Output |
| Red | 2 | Battery Positive |
| Black | 3 | Regulator Ground |
| Green | 4 | Regulator Output |
| Orange | 5 | Ignition Switch |
If you have any issues with the charging circuit, it’s likely that one of these components is faulty. The most common issue is a bad regulator, which can cause the battery to overcharge or undercharge, leading to a dead battery.
Ignition Circuit
The ignition circuit is responsible for starting the motorcycle and keeping it running. It consists of the ignition switch, coil, spark plug, and associated wiring. The wiring diagram for the ignition circuit is as follows:
| Wire Color | Wire Number | Component Connected To |
|---|---|---|
| Black | 6 | Ignition Coil |
| White | 7 | Ignition Coil |
| Orange | 8 | Ignition Switch |
| Blue | 9 | Ignition Switch |
If you’re having trouble starting your motorcycle or it’s stalling out while you’re riding, it’s likely an issue with the ignition circuit. The most common issue is a bad coil or spark plug, which can cause a weak or no spark, leading to difficulty in starting or stalling.
Lighting Circuit
The lighting circuit is responsible for illuminating the various lights on your motorcycle, including the headlight, taillight, and turn signals. It consists of the battery, lighting switch, bulbs, and associated wiring. The wiring diagram for the lighting circuit is as follows:
| Wire Color | Wire Number | Component Connected To |
|---|---|---|
| Brown | 10 | Headlight |
| Blue | 11 | Turn Signals |
| Green | 12 | Taillight |
| Red | 13 | Lighting Switch |
| Orange | 14 | Lighting Switch |
If you’re having issues with any of the lights on your motorcycle, it’s likely an issue with the lighting circuit. The most common issue is a blown bulb, which can cause a lack of illumination or a flickering light.
Accessories Circuit
The accessories circuit is responsible for powering any additional accessories that you may have on your motorcycle, such as a GPS or heated grips. It consists of the battery, accessories switch, accessories, and associated wiring. The wiring diagram for the accessories circuit is as follows:
| Wire Color | Wire Number | Component Connected To |
|---|---|---|
| Brown | 15 | Accessory |
| Purple | 16 | Accessory Switch |
| Red | 17 | Battery Positive |
If you’re having issues with any of the accessories on your motorcycle, it’s likely an issue with the accessories circuit. The most common issue is a blown fuse or a faulty switch, which can cause a lack of power to the accessory.
Frequently Asked Questions
What is the most common issue with the wiring on a 1981 Harley Davidson Sportster?
The most common issue with the wiring on a 1981 Harley Davidson Sportster is a faulty regulator, which can cause the battery to overcharge or undercharge, leading to a dead battery.
How can I troubleshoot an electrical issue on my 1981 Harley Davidson Sportster?
The first step in troubleshooting an electrical issue on your 1981 Harley Davidson Sportster is to check the wiring diagram and identify the circuit that’s causing the problem. Once you know which circuit it is, you can check the various components in that circuit to see if they’re working properly.
Can I replace the wiring on my 1981 Harley Davidson Sportster myself?
While it’s possible to replace the wiring on your 1981 Harley Davidson Sportster yourself, it’s a complex task that requires some knowledge of electrical systems. If you’re not confident in your ability to do it yourself, it’s best to take your motorcycle to a professional mechanic.
How often should I check the wiring on my 1981 Harley Davidson Sportster?
It’s a good idea to check the wiring on your 1981 Harley Davidson Sportster at least once a year. This will help you to identify any potential issues and address them before they become major problems.
Is it safe to ride my 1981 Harley Davidson Sportster if there’s an issue with the wiring?
It’s not safe to ride your 1981 Harley Davidson Sportster if there’s an issue with the wiring. Electrical issues can cause the motorcycle to stall, leaving you stranded or causing an accident. If you’re experiencing any electrical issues with your bike, it’s best to address them before riding.
Conclusion
The 1981 Harley Davidson Sportster is a classic motorcycle that’s still loved by many riders. Understanding the wiring diagram is crucial to troubleshooting any electrical issues that you may encounter with your bike. By following the guide and carefully examining the wiring diagram, you can identify and repair any issues with the charging circuit, ignition circuit, lighting circuit, or accessories circuit. Don’t hesitate to seek professional help if you’re not confident in your ability to troubleshoot or repair the wiring yourself.
