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Discussion Starter · #1 ·
EDIT: SKIP TO THIS POST (CLICKS) FOR NEW ISSUE, DISREGARD THE REST OF THIS POST.



Just as I was pulling up to a stop sign after a nice long ride, all of a sudden my bike stalled. Starter button did nothing. Lights were off. Pulled over, and the main fuse was blown. Put in my spare, and started the bike up. The lights were all flickering/flashing and I realized that the blade in the fuse was slowly melting. When it finally melted and did its "pop" of course the bike shut down and everything turned off.



I have an ignitech and I have an aftermarket ignition switch wired to give power directly to the ignitech when switched to "accessory" and then to everything else at "on." I switched it to ignition only and watched the fuse intently. Nothing changed. Turned the bike on, started it again. Same as the 20A fuse, stayed on for a bit, but the fuse slowly broke and the lights were flickering as this all happened.



The only noticeable issue I've had lately is my starter...it's been acting up for a few months, and I should've worked on it sooner...actually, I was on my way to my uncle's house to take it off and work on it when my reg/rec blew >,>. When hitting the starter button it'll click and turn over a bit and stop, and then if I keep holding the button or if I let go of the button and push it again, then it'll turn the engine over normally. I also have a neutral light that doesn't always come on, but even when it doesn't come on, the bike will still start without the clutch if the bike is in neutral, and a few seconds after the bike starts the light will come on.



Anyhow, I was very fortunate to have some friends that I knew in High School come driving by in their pickup truck. They expected to be able to help fix the bike, but when I told them that I was only a mile from my destination, they happily loaded it up using their "Polk County Edition Tailgate" aka, two pieces of spray painted plywood, as one of them sat on the bike while they drove over to my uncle's place.



Horribad image as I was trying to help and take a pic at the same time







My uncle told me that since the lights were flickering when the bike ran for a bit, he suspects the reg/rec. First we tested continuity from the wire that would go to the battery through the fuse and to the frame. With the key set to ignition only, there was no continuity to ground. When set to "on" there was continuity to ground.



I looked at my manual to test the reg/rec and it said to check continuity between one of the three yellow wires and a red and white wire...and then with a green wire I believe (We did what the book said, I just can't remember the colors off of the top of my head).



It said that one way there will be continuity, the other way there will not be continuity. We tested everything it said to test, and there was no continuity at all. Then we tested continuity between what I think was the green and red/white...I think that they're only supposed to have continuity one direction, but they had continuity both directions.



So, looks like it's the reg/rec, but I've never heard of the reg/rec blowing the main fuse. My uncle told me that "since it's bad it was flickering the lights, and that's probably what blew the fuse."



So, this means that I'll either have to get one from the salvage yard, or find one locally...or I'll be stuck at home until Tuesday waiting for something to ship overnight. Which means no work or class. Lovely.



I own a 1973 Honda CB500 as well...does anyone know if they might be compatible? Numbers don't match, but they look similar. But I don't want to blow something else up on my bike just to have it going for a few days while I wait for the correct part.
 

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It could be the regulator/rectifier but I suspect it's not as they are very reliable.



Here's a simple test. Simply unplug the regulator/rectifier and see if the fuse still blows. It won't hurt anything to unplug it - the charging system simply won't work.



If the fuse still blows, the R/R is not the problem. Then it would be appropriate to remove the main fuse and install a 12V test light in its place. With a short in the electrical system the test light will glow brightly. Then start wiggling wires and unplugging things until the short is gone.
 

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Discussion Starter · #3 ·
It could be the regulator/rectifier but I suspect it's not as they are very reliable.



Here's a simple test. Simply unplug the regulator/rectifier and see if the fuse still blows. It won't hurt anything to unplug it - the charging system simply won't work.



If the fuse still blows, the R/R is not the problem. Then it would be appropriate to remove the main fuse and install a 12V test light in its place. With a short in the electrical system the test light will glow brightly. Then start wiggling wires and unplugging things until the short is gone.


Good call. I didn't realize that the R/R wasn't necessary. Rather than spend money on another, I'll do this tomorrow with a box of extra fuses on hand. Glad that there's a more surefire way to test it than the continuity test.



There also was some corrosion in the connector block for the R/R as well, so that'll be nicely cleaned and coated with some dielectric grease.



If it turns out that it's not the R/R, is it possible at all that my starter issues for the past few weeks could be related to what's blowing the fuse? If so, that's where I want to look first, since it's been acting up. Same with that neutral indicator.



Another thing I realized was that one of the wires in the harness was pinched in the steering stops...it was a ground wire, but it seemed to look okay. Maybe it's possible that without it, something is shorting out, causing the fuse to blow?



Sorry, electronics aren't my strongpoint....ugh, just as I was getting into some engine work on the thing another electrical issue pops up.
 

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I doubt that your starter issues are the cause of the fuse blowing. They are generally out of the system once the bike has started.



I would do some more checking on that pinched wire. Re-confirm that it is a ground, and then splice it back and reroute it out of the way. After you do Allan's stator unplug, do his suggestion of using a test light in lieu of the fuse. You will have to take out the fuse for any lights that are on with the key on (headlight, running, tail), and unhook the ignitech. If the light is on with these unhooked, you have a short to ground somewhere in the harness.
 

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I would do some more checking on that pinched wire. Re-confirm that it is a ground, and then splice it back and reroute it out of the way. After you do Allan's stator unplug, do his suggestion of using a test light in lieu of the fuse.


Blue Fox,,I know I am usually the one telling people to unplug the stator,,but this time it wasn't me.




Cramer,,on most Hondas the power wires are black,,so if it was a black wire that was pinched it would not be a ground.
 

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Discussion Starter · #6 ·
I spent a lot of time studying the wiring on this bike when I changed to the aftermarket ignition switch. It's the same switch that works with the '82 model, I just couldn't find a non-used switch that was meant for the 78-81 CX's, and already had changed the wiring so it'd work with a thumb switch as I waited for the good switch to show up.



It was a green wire that was pinched, so I know for sure that it was a ground. I checked all of the other wires and none of them had any insides showing, but that doesn't mean that there can't be a shorted wire somewhere else.



As for the switch, just to rule it out, all I did was cap off the ground wire that went into the old switch, as well as the wire that connects to the killswitch (so turning the key off wouldn't kill the engine when I still had the CDI, it will now with the ignitech). I then spliced the brown wire with the brown and white wire, aka the lights wire with the tail light wire. This eliminated the parking light option from my switch, but one of my original problems that clued me in to my ignition switch going bad (which I stupidly ignored) was the tail light not always coming on. So with tying it directly to the brown, it's always on when the key is on, and always off when it's not set to on.



Then I hooked the power from the battery (red) in and then power out to the bike (black) and then power to my ignitech (another red one, I think I put stripes on it though). Off-no connections to anything. Acc- Battery to ignitech. On- Battery to ignitech and to black wire, thus everything else on the bike. Park- I think it either gives power to ignitech, or doesn't give power to anything...I forgot. I know it doesn't blow the fuse though, I tested it when I first tried the switch.



I've had it on for like 2000 miles now I think, probably more. No issues with any electronics until now.
 

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Just FYI but I had a wiring issued that showed up when the handle bars were turned all the way to the right. Check the wiring on the right side of the frame and turn the bars all the way and notice how they are being pulled. Good luck.
 

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Discussion Starter · #8 ·
SKIP TO BOLD TEXT FOR NEW ISSUE.



So, I installed one of those inline blade fuses and got rid of the glass fuse. Started the bike up without the R/R, and it started fine. Then I thought...well, I have all of these extra fuses, why not do some trial and error. Plugged the R/R back in, and the fuse was fine. No flashing lights. Did a test on the battery....13.3 volts. Revved the engine to 5-6k RPM, and it only went up to about 13.7 ish. I don't think that that's good....it may not have even really gone up at all, the multimeter has a bit of a margin of error.



My uncle told me that maybe when it heats up it starts to blow the fuse. Interesting.



Then it dawned on me. I was turning left when the fuse blew. The lights would flash at the same rate my blinker flashed. So after my uncle says "Ok, I have stuff to do, you can probably get it home like that, just unplug the R/R if you blow a fuse again to get it the rest of the way home" I immediately hit my left blinker, and instead of it blinking, my lights flashed like they did before, and the fuse blew. "I really really hate you." Hehehe.



So instead of troubleshooting the electrical connection, I just rode around for the rest of the day using hand signals.



I thought that it was because I installed Silverstar 1157 bulbs, so I bought new ones, but opening the left cover showed nothing out of the ordinary. Hmm. Then it dawned on me again...a few weeks ago the signal stalk broke off (idiot PO welded it on to the headlight ears) so we had to make a bracket and screwed it in with self tapping screws. Well, one of those screws grazed one of the wires just enough so that the vibrations would work the insulation off slowly, and the bracket isn't perfect so the stalk likes to move around a bit too. I moved the stalk up a bit, and then all of a sudden I would get a working blinker with no blown fuse. I then maneuvered it around, and got all of my lights to flash again, and the fuse to blow.



Wrapped it in electrical tape, and now I'm good as new.



Ok, this isn't really a "new" issue, but it came up when looking into the fuse



It's a good thing that this happened or I wouldn't have noticed my battery not charging past like 13.7 something, unless that's an ok place for it to be at 5500 RPMs. I remember reading somewhere it should be in the 15s or something, but maybe that's a different test. So either it's the R/R or the stator going out, though it had nothing to do with this issue.



We also, as mentioned before, tested continuity between the red wire and the green wire on the R/R and the yellow wires, and there was NO continuity no matter what direction we did it (book says it should have continuity going in one direction or the other). Then we checked between green and red. We thought that it also should only have continuity going one way (though the book only gave a diagram for those) but they had continuity both ways.



So, should I be worried about the R/R or Stator? We only checked because we thought that those were my initial issue, but it turned out to be a pinched wire from a rushed job. Oopsy. Didn't notice voltage rising much at all from idle to 5000 RPMs, though it stayed about 13. The only thing I'm running that draws more electricity is my ignitech.
 
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