Voltage Regulator Failure
Seasoned HDF Member
Joined: Jun 2006
Posts: 30,875
Likes: 32,915
From: King George, VA
I found out the expensive way that the instructions in the sticky on the Electrical/Lighting/alarm forum are not correct.
The sticky says if there is continuity from the DC output of the regulator to the AC input of the regulator, the regulator is bad. The new regulators don't check like that.
I followed those instructions when I was having a charging issue. I went through two regulators that according to the sticky, where bad. Before installing the third regulator I did a complete inspection of all the wires on the bike. I found the DC line from the regulator to the battery had rubbed against the frame to the bare wire. The wire is zip tied to the bottom right side frame member and hard to inspect unless ya cut the zip tie.
I mentioned this to my local indy and he went and checked several Harleys in his shop and found the regulators all had continuity from output to input.
Now, before ya go off and start asking if I had the ignition on or was the bike running, think about this. The only way to check for continuity from the regulator output to the regulator input is to have ALL wires disconnected. As if it were sitting on the bench, 20 feet away from the bike.
The sticky says if there is continuity from the DC output of the regulator to the AC input of the regulator, the regulator is bad. The new regulators don't check like that.
I followed those instructions when I was having a charging issue. I went through two regulators that according to the sticky, where bad. Before installing the third regulator I did a complete inspection of all the wires on the bike. I found the DC line from the regulator to the battery had rubbed against the frame to the bare wire. The wire is zip tied to the bottom right side frame member and hard to inspect unless ya cut the zip tie.
I mentioned this to my local indy and he went and checked several Harleys in his shop and found the regulators all had continuity from output to input.
Now, before ya go off and start asking if I had the ignition on or was the bike running, think about this. The only way to check for continuity from the regulator output to the regulator input is to have ALL wires disconnected. As if it were sitting on the bench, 20 feet away from the bike.
4th Gear
Joined: Jun 2016
Posts: 8
Likes: 2
From: arkansas
Glad I found this thread. I was having some electrical issues(stranded).
Did all the tests and found I was getting AC from the engine, but the battery voltage didn't increase while running or when revving.
Not sure what the problem could be at this point. I have AC power and replaced my regulator with a cycle electric model. I am going to double check my connections tomorrow. Hopefully that's it.
Possible I got a defective part??
Did all the tests and found I was getting AC from the engine, but the battery voltage didn't increase while running or when revving.
Not sure what the problem could be at this point. I have AC power and replaced my regulator with a cycle electric model. I am going to double check my connections tomorrow. Hopefully that's it.
Possible I got a defective part??
Cruiser
Joined: Aug 2013
Posts: 101
Likes: 2
From: bay area calif
i have 14.93 volts going to my battery from my regulator when i rev it up wony go above that 14.93 no matter how high i rev it up. ive read 14.7 and 14.8 .is this the max is my reading acceptable ? i dont want to fry a new battery
Banned
Joined: Jul 2009
Posts: 7,406
Likes: 834
From: Straight Jacket Memories and Sedative Highs
14.7 is considered the highest. Is your meter good enough? Does that make a difference?
I dunno. If you have a light bulb blow, then I would probably change it out, but if not wait and see. I'd be little concerned, but it is close, and regs cost money.
Be nice if you could check your meter on another bike, to see if it reads the same. I am using a $250 fluke meter to read .10s
I dunno. If you have a light bulb blow, then I would probably change it out, but if not wait and see. I'd be little concerned, but it is close, and regs cost money.
Be nice if you could check your meter on another bike, to see if it reads the same. I am using a $250 fluke meter to read .10s
Supporter
Joined: Jan 2007
Posts: 15,788
Likes: 5,621
From: along the shore of Mishigami
Install a correct size battery and install the correct regulator from Cycle Electric for your bike. The HD charging will take itself out when one component fails, because it's trying to compensate for what else failed. Cycle Electric makes a great product.
HD Forum Stories
The Best of Harley-Davidson for Lifelong Riders
7 Surprising Harley-Davidson Products that Are Not Motorcycles
Verdad Gallardo
8 Best Harley-Davidson Motorcycles Ever
Pouria Savadkouei
10 Worst Harley-Davidson Motorcycles Ever
Pouria Savadkouei
Killer Custom's Jail Break Is The Breakout That Refused to Blend In
Verdad Gallardo
Crazy Bunderbike Build Looks Amazing, But Is It Impossible to Ride?
Verdad Gallardo
Harley-Davidson Reveals Super Cool Cafe Racer Concept
Verdad Gallardo
Engraved Rebellion: Inside Bundnerbike's Glam Rock II
Verdad Gallardo
10 Motorcycles You Should Never Buy
Joe Kucinski
