Hey all.
I have a 78 R100RS that I acquired (bought) from my step father back in 2018. Cosmetically, it needed help, but over all the engine was taken care of and was started every few months, and was stored correctly. I keep it at my in-laws house and work on it when I can so my updates and upgrades are usually spaced out about 3 months, but when something goes wrong, I sometimes have to wait until the next time I visit to try and fix it. This also gives me a fair amount of time to research on the subject. Luckily when we visit, we do for 2-3 weeks so we can get some serious miles on the bikes, as well as some serious wrenching. And with the current state of the world, especially 2020 and 2021 and having the luxury of working remotely, I have been able to make significant strides on the bike and get it to about 90% to where I want it to be. Bikes runs, nothing smokes, all electric works. Its almost damn near perfect.
On that note, why am I here and what is my problem.
This problem has been plaguing me for quite some time now.
I have upgraded all lights to LED back in 2020.
Katdash LED dash
LED bulbs in voltmeter and clock
LED front parking light
Cyclops LED headlight
LED rear tail/brake light
Left and Right LED turn signal bulbs (with FL3 flasher relay)
Ok, so now the problem.
There is a light leak happening on the left side turn signals when the bike's kill switch is in the 'run' position. This includes when the bike is running and not running. All the electronic components I listed up above work fine, just when the turn signals are not activated, we have a light leak.
- When the bike's kill switch is on the 'off' position, all of the electronic components I listed up above work fine, noting that the dash is not illuminated (assuming thats normal), the light leak on the left side turn signals is gone, but when the left side turn signals are activated (both front and back) I get a clicking sound (imagine snapple freshness/safety seal bottle top) from a little place just south of the starter relay (behind the left side panel: there is a small rubber round thing. No idea what that is (see the attached diagram for what 'i think' it might be.
So does anyone know what this is or how this works? I'm not as electrically inclined to fully understand these things, so by all means, please speak layman to me.
I am at my in-laws now and have 5 days here to figure out this problem, otherwise I won't be working on it until maybe July? Any and all help would be swell.
This is the attached diagram I referred to.
Could be a bad/corroded ground connection. As mentioned many times here, a dioxide paste will do wonders on all electrical connections. Just a dab. It's a good practice when working on any electrical to apply when assembling
First thing I’ll offer; my 78 RS had a piezo beeper audible turn signal indicator that lived under one of the battery covers. I eliminated it umpteen years ago. There is also, nearby I believe, a relay associated with the beeper. I would ditch both those items. As far as I recall, both the beeper and the relay can be unplugged without detriment. See what happens then.
I missed the part about the clicking. Dave is correct about that. It should beep w ýour turn signals but yours is old and frozen up. No harm in disconnecting
Question; when you say you have no dash lights when the kill switch is off, are you saying the oil/gen/neutral lights are inoperable? Are the instrument illumination lights still on? I think that is what your chart says.
I'm sitting here looking at a schematic, and the kill switch interrupts 12v+ to the ignition coils, that is all. It affects nothing else. So your scenario is very perplexing.
I’d check your frame ground at the left coil. Make it’s clean and tight.
Point of interest - I converted mine to all LED lighting also, exactly as you have done (including the Cyclops headlight). I purchased the turn signal flasher from KatDash. Did you as well? LED’s seem to be very sensitive to electrical issues. I immediately had a problem with my oil pressure light. The problem did not show with the old bulb. I replaced my pressure switch and it functions perfectly.
Just saw something in your initial post. “Somewhere south of the starter relay under the left cover”. That’s not the starter relay. The starter relay is under the tank. That’s the relay for the beeper. Unplug that relay and the beeper.
My dash lights go off when the kill switch is turned off w the key on
I wish I could test that on my bike, but I also jumped out the kill switch in the headlight shell years ago, so it is not operative.
@4949 "piezo beeper audible turn signal indicator"... Is this that round rubber piece under the battery cover? Under the side panel just south of another relay?
@4949 "when you say you have no dash lights when the kill switch is off, are you saying the oil/gen/neutral lights are inoperable? Are the instrument illumination lights still on?"
This is correct. oil/gen/neutral lights are off, but the instruments are still illuminated.
"I converted mine to all LED lighting also, exactly as you have done (including the Cyclops headlight). I purchased the turn signal flasher from KatDash. Did you as well?"
sí, señor. Turn signal flasher came from KatDash.
@4949 "Just saw something in your initial post. “Somewhere south of the starter relay under the left cover”. That’s not the starter relay. The starter relay is under the tank. That’s the relay for the beeper. Unplug that relay and the beeper. "
And the winner is....David Elkow (@4949). I read your post last night, went out to the garage, unplugged that relay and what do you know... NO MORE LIGHT LEAK! NO MORE CLICKING SOUND! I just took that relay plug out and thats it. 2 year old problem fixed. As that little rubber circle piece that made the clicking sound that you ID'd as the "piezo beeper audible turn signal indicator", its ok to just leave that there plugged in? no harm no foul?
This was such a simple suggestions, I wish I had asked this on the forum before I spent all of Saturday taking apart all of the lights and removing the tank to check the grounds, then aimlessly staring at the bike, asking the gods what can possibly be wrong!
Thank you to all of the Airhead community that piped in with suggestions. I absolutely love learning about this bike and challenging myself. I knew I could find the answers here.
yup
I guess leaving the beeper plugged in is ok, as long as everything is working fine. Sure glad it has been healed!
I have to admit though, that I don’t understand the effect of your kill switch - turning off the dash indicator lights. The schematic I have doesn’t jive with that. Of course, like I said, I can’t test my bike. Maybe some of the wiring changed, or schematic I have ain’t so good.
My dash lights go off when the kill switch is turned off w the key on
Correct. On those year models, the handlebar "kill switch" turns off much more than simply the power to the ignition.
Owning an old Airhead is easy.
Keeping an old Airhead running great is the true test.
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