Tech review of the Harley Davidson charging system. Here’s an easy way to make sure your battery is charging. Everyone is at your house and ready to ride. You saddle up and CLICK, your Harley-Davidson does not start. Bob and Mark review an easy way to check your battery and make sure it’s staying charged.
and for Dyna riders:
Dyna Battery Removal and Replacement
Next Service:
Drain Fluids Softail
Drain Fluids Dyna
More on Electrical Troubleshooting
In this quick demonstration of the Harley Sportster battery removal, you’ll learn how to remove your bike’s seat and side cover so you can check on the condition of your battery and its operating components. It is strongly recommended that you remove the negative cable of the battery first and replace it last when servicing your bike. If you remove the positive cable first, you risk causing a dangerous spark if the battery comes in contact with your bike’s frame. Bob has been dealing with these batteries for years and removes the neg from the battery. If this is your first time, we highly suggest removing neg from ground stud on the crankcase boss(see images)with wobble extension.
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Now that you’ve fully serviced your Harley Sportster, you can take the opportunity to check all of the safety features on the bike. Make sure the lights are working properly, the horn makes noise, turn signals are operational, and all grommets are in place. Then you should check the throttle, add oil and fill the tires to the correct level. Once your finished with the service, get out and ride!
*****The service manual states you should follow your negation cable down from battery and remove nut that secures the connector to ground stud on the crankcase boss behind the starter motor assembly. You will need to do the reverse during installation.
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Harley tools are not only specialty tools like JIMS and Kent Moore but many that you have in your garage already. Bob LaRosa gives us a great overview on some of the basic tools we need to service our Harley-Davidson from oil-change to custom part install. Bob shows us that tools are only part of…
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Bob takes you through the step-by-step process for throttle cable service and adjustment, and air cleaner service or replacement. He discusses the different parts in the throttle system, their specific roles and how to clean and take care of them, then teaches you about the elements of the air cleaner.
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I have a 02 Harley Buell Blast 500 and I hooked up battery backwards and my wires smoked up white. I quickly switched battery around and connected correctly and again all my wires went up in again in white smoke so I unhooked battery and put on trickle charge. Is my electrical system going to be okay.
Dear Brian,
Thank you for your patience. In response to your question-
Unfortunately, there is a possibility that this may cost more to repair than the bike is worth. Especially if you can not complete the repair yourself.
It depends on the extent of harness damage and whether or not your ECM was damaged.
You may not be able to determine if the ECM or any other electrical components are damaged until the harness is repaired or replaced.
Suggest replacing or repairing the damaged harness. Then, test for all electrical functions.
https://www.fixmyhog.com/video/simplifying-electricity-002170/
https://www.fixmyhog.com/product/overview-of-electrical-systems-part-1-download/
https://www.fixmyhog.com/video/welcome-to-fix-my-hog-electrical-002169/
https://www.fixmyhog.com/video/watts-law-002179/
Sincerely,
Mark
Fix My Hog
I have an 08 Electra Glide Ultra Classic and the voltage dropped down while riding and the headlights dimmed. I revved the bike a few times and it came back up and brightened the headlights. No issues starting the bike, tho. What could cause this?
Hi Chad. It can be a failing charging system. Make sure that battery cables are clean and secure. Perform a charging system test.
CHARGING SYSTEM
https://www.fixmyhog.com/video/charging-system-diagnosis-002187/
Mark
Fix My Hog
Thank you. I’ll take a look.
I have a 2026 Harley Davidson Softail Slim S, the battery went bad 2 weeks after I got it, I replaced the battery and everything seemed fine, then I noticed that If I did not ride or turn on my bike the battery would lose its charge. I did not ride for one day and the bike did not turn on, tested the battery and it was at 20% I put it on a charger, got it up to 50 % and got the bike to start. Kept the charger on and saw that the battery charged right up to a 100% I am wondering what could be causing this? A bad voltage regulator maybe?
Hello Kristopher,
Yes, the issue can be a bad regulator. We suggest that you perform a full charging system test.
CHARGING SYSTEM
https://www.fixmyhog.com/video/charging-system-diagnosis-002187/
Mark
FMH Expert