I noticed it while riding my 79 RS at night which I don't usually do. It is very dim yet visible. When using the signals the gen light becomes brighter, but not noticeable in daylight. The battery doesn't seem to be affected by this as it's stable with a 12.24 charge most of the time. Any ideas what would cause this? I've just returned from an 800 mile trip with no consequences. But I don't know how long this has been going on. It could be very recent.
Generally, the dim generator light indicates a poor connection - somewhere. That could be in the ignition switch, the starter relay connections, wiring between the alternator and diode board, corroded voltage regulator contacts, or a poor ground to the diode board. I had a similar problem and found that after replacing the wiring between the alternator stator and diode board the light extinguished completely. A night ride was the only time I could see the dim glow. Good luck!
Is it possible one of the instrument illumination lights is showing through? And when you turn on your turn signal, is the indicator also lighting the lens for your charging light? It would make sense that get lighter when the turn signal was on. I would guess the best way to test that would be to run your engine at night with the lights off to see if the charge light comes on, that is, if you have a bike that you can turn the lights off.
I'd also check the brushes in the alternator. I've heard it said that if they are more than half gone, the spring tension on them lessens enough to affect output without totally stopping charging. Someone else will have to chime in on what their length should be either new or at the service limit.
I recently replaced brushes that were about 1/3 worn. It fixed the gen light getting brighter with higher revs, but the light still glowed slightly. I noticed a failed solder joint on the diode board, so I replaced it, but still had a dull glow. Finally replaced the VERY crusty wiring between the diode board and alternator; glow was gone!
I have seen diode boards cause dimly lit charge lights, quite a few bad rotors, and ground wires shorting out on the diode board. Brushes seem to be a very common cause of issues here on the net. In real life? I see them lasting and working perfectly for 100,000 miles + ALL the time. The brushes seem to be the floats of the charging system? My point is why replace them when they last for almost ever and work perfectly the whole time? The brushes can be very short and there is still plenty of spring tension on them if the springs are installed correctly. The only trouble with brushes I have ever seen wasn't really the brushes at all but . . . . Twice I have seen aftermarket rotors with the slip rings turned off center. The bouncing brushes caused lower charge rates. No glowing light, just a volt lower charge rate than what it should have been.
Mine was a rotator. I could only see mine at night and I kept seeing 14v. I checked grounds, redid every connection I could touch and it improved, but never went away. Then I took a road trip. On my way home, as the sun went down, my voltage started to drop. I made it home with very little battery power left. I charged the battery and rode to work the next day, and everything was fine. Coming home in the dark, the light started to glow again. I tested the diode board, rotor, stator and voltage regulator. Everything tested OK. It took me about week of testing to figure out I needed to heat the rotor. Once I did that, the resistence would climb showing I had a broken wire. I replaced my system with an Enduralast permenant magnet system and all is well. I don't know if you have a rotor going, but I thought you might find this helpful if everything else checks out.
Hi everyone, I have the same issue. I bought a 1984 r100 RT and kind of had to charge the battery every 5 days ( not doing long distance journeys, mainly city rides). Then I decided to make a cafe racer out of the bike, I removed all indicators as it is not required for bike older than 85' in NY state, and changed the stop and tail light for some LED red lights bought at Autozone. Everything worked fine for a bit, except for the other day, while I was riding, the GEN light came on ( even over 3/4/5K RPM) and it seems to be draining the battery very quickly. I had a quick look at the outside of the bike, and I found, connecting to the STARTER RELAY, that one of the red wire that splits, was completely burnt. The plastic around the copper is completely burnt off. That specific wire is either : 1/the one going to the #30 on the board in the head light bucket, 2/the one splitting again toward the ignition light switch 3/the one going toward the clock... Now my concern is that, I dont think any of these 3 option could cause an issue with the charging system, AND I havent opened the front of the engine just yet. And would love not to have to open it... Could anyone maybe indicates me which way would be the simpliest and less costy solution? And if I do have to open up the front cover of the engine, what exactly should I be looking for that could be causing the GEN light to be on AND the battery not charging ( which I repeat was already a bit of an issue when I acquired the bike). Thank you very much in advance for any help!
You probably now have TWO faults. 1) Alternator not charging. 2) Short somewhere that has caused the melting insulation. As this can cause a fire and set your bike up in flames .. i recommend you do this first. Trace by sight and feel along the wires going away from the battery from the melted wire - you are looking for any nicks or ware that goes through the insulation. If you find any of that then ... repair the damage, and prevent it occurring again. Then replace the meted insulation by replacing the wire/s. 1a) What is so hard about removing the front engine cover? Two screws and your done. Other than disconnecting the battery at the negative terminal .. it is much easier than say an oil change. If you have EXACTLY the same issue (and you say the battery is not charging .. headtubes was charging .. so here you have a different issue.. possibly 3 faults!) .. then follow the information given previously. If it is different .. start a new thread ...
Thanks for your quick reply and help! 2/ I am meant to change that cable. I have bought a wire with higher resistor, just in case it keeps on warming up, next time it wont be as warm. BTW, the wire went smoking when I was next to the bike, no key in ignition, just decided to smoke out that very second I was in front of it. I also didnt want to cut the insulation around the cable as it is all original and what I will be replacing it with will never be quite as good material. 1/ The only issue for the fornt covered isn t much for the work involved, it is just the location : the street. Living in Brooklyn isnt the best place to own a motorcycle as it has to sleep outside all the time. Now, once I remove that front cover, what exactly should I be looking for? I have read on many forums that the brushes might be worn out? or alternator to replace entirely? I do not have the manual and only try to find a trouble shooting list. Thanks again
2/ Replacing the wire ... MAY NOT FIX this problem! The replacement may simply burn up to. And, if yu are not lucky, this could set fire to the bike ... and it burns to the ground. Please read my previous post on what to do to find the problem for 2/. ------------------------------------------ Some have replaced main bearings under a tin roof many hundreds of miles from home. Removing and replacing the front cover can be done in less than 5 minutes. Fault finding the alternator will take a lot more time than that .. if you don't have that time available ... take the bike to a mechanic and pay for the repair. The alternator is the same principle as used on a car .. there are enough articles on how these things work on the web .. that they are easy to find. Look. A start can be made here http://www.ibmwr.org/r-tech/airheads/charge.shtml. The bike can be ridden with the front cover removed... I'd not do it in mud.
Replacing a burnt wire with a good wire before you have fixed the problem may cause more damage than you anticipate. The burnt wire is only a symptom of a problem somewhere else. The new wire will carry more current and could then be the ignition the fire needs to get started. I'm not up on wiring in an '84 bike but this idea is a basic principle. Do you have a wiring diagram? They are in all the modern Airhead manuals. Find out what that wire goes to.
I think it is just time for me to accept that I need to put the bike away for winter so I can have a proper look at it and fix it! I do have a wiring diagram, I will have a look at all that this week end and will let you guys know what I find. Thanks a lot for your help!
