Hello, im planning to work on replacing my turn signals to another type (not the stock bullet).
whats the proper step on how tneedo do it? read somewhere about removing the main fuse to be safe and put it back after finish. BUT heard that theres a needed process to remove the main fuse other than just unplugged it straight up.

Whats the correct way to remove the main fuse?

*2024 street bob

TIA

 

If you have a security "Siren", the process is to have the FOB close by, turn ignition switch on, pull fuse, turn switch off.

If you don`t have a security "Siren", you don`t have to mess with the ignition switch, leave it off and just grab ahold of the fuse and yank it out...

 

ahhh so it is safe for me to just yeet the fuse out?

thank you so much

 

1. Read your owner's manual first, it will have the proper procedure like Dan said.
2. If you do not already have one, get a HD Service Manual (not owner's manual) for your bike.
3. Your bike has a CAN Bus system, be careful when installing anything non-OEM as it may not work correctly unless certified plug and play.
4. More reading on CAN Bus below.


Communications System: HDLAN

In this article we will try to explain in a simple way the latest Harley-Davidson communication system, the HDLAN.
This new technology will allow the entire H-D range to have ABS brakes, less wiring and the elimination of the ignition key, among other improvements.

Internet inside your motorcycle
One of the first questions you may ask yourself when hearing about the communications system is, why does a motorcycle need this? The answer must be found in the technological evolution to which automotive brands have been forced in recent years in order to reduce emissions and comply with increasingly demanding regulations and at the same time improve safety standards and driving quality .
With the adoption of electronic injection, it is necessary for the different sensors and actuators to communicate with the ECM or control unit of the vehicle.
This communication occurs in digital language, that is, with “zeros and ones”, just like our personal computer or a tablet does.

Let's give a simple example:
-The pilot operates the left turn signal switch.
-The handlebar button module sends the message "flashing button activated" to the network.
-The BCM (electric controller) reads this message and energizes the indicators on the indicated side, it also searches for the speedometer signal and also that of the inclination sensor, thus determining how long the indicator will remain on.
-At the same time, the speedometer also reads the message and turns on the dashboard indicator light.
All these messages are sent through a cable, called the “Data Bus”, which is a kind of Internet inside the motorcycle, which allows the modules to communicate with each other.

HDLAN
Until 2011 the communications protocol used 1 cable and was based on the J1850 standard. As of this year, a faster protocol, with 2 communication cables, the HDLAN, based on the CAN BUS automotive standard, was used in the Softail models and later in the Dyna family.

In order not to get lost in technical details, imagine that J1850 is like Internet based on the RTB telephone line, old and very slow. On the other hand, CAN BUS would be like ADSL, faster and more modern.

Using the HDLAN (Harley-Davidson Local Area Network) communication system has several advantages:
-Higher data speed
-More security against data loss
-Reduction to the minimum expression of the wiring, relays and fuses on the motorcycle

-More compact and unified modules
-Improved diagnostic ability



The heart of the system is the BCM, a module that receives power directly from the battery.

In previous models of this system, if we pressed the horn button for example, what we did was connect the battery power with the horn so that it would sound. Electricity went from the battery to the button on the handlebar running through the entire bike and then back down from the button to the horn.
With HDLAN, when we press this button, what happens is that it is “published on the Internet of the motorcycle” that we want the horn to sound, so the BCM reads the message and sends electricity directly to the horn to make it sound.

There is no more electricity going up and down the handlebars to activate it, just a message. This applied to the entire electrical system of the motorcycle means that all the modules (Speedometer, ABS, BCM, ECM or control unit, Radio ...) can communicate with each other, obtaining superior performance and reliability.

Improvements such as those that have appeared in the Sportster models such as the possibility of knowing the revolutions or the gear at which we circulate on the odometer, the introduction of ABS, the disappearance of the ignition key and the optimization of the battery compartment are possible thanks to this technology.

Conclusion
It is evident that the owners of Custom models are not the biggest fans of technological sophistication, but knowing that it will inevitably involve our lives (and our motorcycle), it is at least comfortable to know that in some cases it is used to simplify complex systems, making them at the same time safer and more reliable. This magical mixture of Old School & New Technologies is produced, which will keep us rolling free and better communicated.



It seems everything has become increasingly computerized in the past decade or so. We have everything from network-connected refrigerators to pet feeders you can monitor from across the globe and cars that drive themselves (until they don’t).

Naturally, our motorcycles have followed suit. Gone are the days of cleaning your ignition points and your pilot jets to keep your ol’ BSA going.

Thanks to decades of engineering iteration, vehicles are more complex than ever. Instead of one or two computers, most modern vehicles are equipped with an array of control units that are individually responsible for systems such as engine management, anti-lock braking, traction control, and chassis systems.

These computer modules work in unison to conduct a symphony of ones and zeros, transferring information between each other to keep things running as intended.

It’s All About Communication

With some vehicles having more than 100 individual control units, manufacturers needed an efficient system for them to communicate with each other. Enter the CAN bus standard.

All these control modules utilize a standardized networking communication protocol called controller area network (CAN) bus to transmit and receive data in real time. The CAN system is able to link each of a vehicle’s computers over a network of just two wires.

Think of it as the central nervous system of the machine.

A motorcycle’s electronic components, like the engine control unit (ECU), ABS module, and display unit, can communicate with each other by sending and receiving messages through the CAN bus. Messages can range from simple status updates (such as speed or throttle position) to more complex things, like detailed error messages or specific control commands from one module to another.

For example, let’s picture a scenario where the traction control module detects wheel slip. It immediately sends a dispatch to the ECU to cut power to the rear wheel until traction is regained, at which point power output returns to normal.

All this happens seamlessly in mere fractions of a second, often with the high-horsepower machine’s pilot oblivious to the life-saving intervention—save for the TC light blinking away on the dash.

Shiny Sides Up

The main advantage of the CAN bus system is, as I mentioned above, real-time communication. This is what makes features such as sophisticated, lean-sensitive ABS or traction control that require high-speed communication and feedback between components possible.

Another advantage, believe it or not, is reduced complexity. The two-wire system replaces the multitude of individual cables that would be required to connect each computer individually, thus cutting weight and saving space.

Finally, in diagnostics and troubleshooting, mechanics often have a much easier time when they can connect diagnostic tools to the CAN system to read error codes, monitor sensor data, and identify potential issues within the motorcycle's systems quickly and accurately.

Rubber Sides Down

But can the CAN have disadvantages? Well, although it often benefits mechanics with the proprietary diagnostics software, it’s obviously not as easy as popping your float bowl off your carburetor and blowing it out with some carb cleaner to get you back on the road when something does go wrong.

Another problem—as many riders are likely already aware—is the CAN bus system’s extreme sensitivity to change. Trying to power a GPS or phone charger from the wrong wire or even installing turn signals with significantly different power requirements to the factory ones can cause problems with the CAN system, including mysterious error codes or disabling the bike altogether in extreme cases.

This is because CAN works on a very narrow and specific voltage range and utilizes changes in voltage to carry messages between components. Changing power draw in either direction can adversely affect these messages and suddenly they’re all Greek to the CAN system, generating error codes.

Next time you want to install auxiliary lights or a louder horn, you’ll have to do your homework to see if your bike uses CAN bus. Some machines even monitor the status of your turn signals and something as simple as upgrading your indicators could cause a CAN bus fault.

Many motorcycles come equipped with accessory circuits specifically to avoid these situations. If you don’t have that option, some other workarounds include CAN-friendly accessories that are designed with your bike in mind or separate control modules that work with a CAN system and will not interfere with its operation.

Unfortunately, aftermarket manufacturers are not always clear about whether their products will play nicely with CAN, so some digging may be required. Often, if you have an issue, the computer will point you in the correct direction via the display. That’s not guaranteed, though, and a trip to your dealer may be in your future if you get really stuck.

If you’re electrically accessorizing something like a new BMW R 1300 GS, I’d suggest doing one thing at a time if you’re not 100% sure of compatibility. That way you can easily go back and remedy the issue if one does present itself.

We CAN’t Have it All

Overall, the advantages of CAN bus make it a reliable and efficient communication protocol for managing the complex electronic systems in modern motorcycles. It contributes to better performance, safety, and user experience.

While it is true that our bikes have become more complex and often can’t be serviced without at least some help from the dealer, on the whole, systems like CAN bus make for a better overall user experience.

The high-speed and data-dense communication make sophisticated systems such as dynamic suspension control, high-performance ABS, lean-sensitive traction control systems, and stability control systems possible. Without CAN bus technology, we wouldn’t have the spectacular machines we have come to love from today’s motorcycle market.

So, for now, CAN bus is an automotive industry standard that’s here to stay—at least until someone comes up with the next, better standard.





NOTE:
The above information, while credible, is worth what you paid for it and should not be considered gospel.
Do due diligence, research and have a H-D Field Service Manual before working on your bike.
You will probably have many opinions and suggestions presented; make sure you research the person providing the helpful information as there are some who provide good information that is useful and some who speak out of other orifices with gibberish. You will figure out this quickly.