Installing aftermarket signal lights - question

I finally decided to put some signal lights on my Mark III. It didn't have them installed when I bought the bike a couple of years back and I have been using arm signals and hoping that Mr. Policeman doesn't stop me.

So far so good, but I've decided to go legit.

Here's my installation question: The signals I bought are nice and compact, but unlike the original Lucas models, have two wire leads instead of just one.

I put Lucas bullet connectors on one lead and assumed I would just ground the other wire.

That set up works fine while I'm holding the lights in the air next to the bike to test (flash perfectly), but as soon as I touch the stem of the signal light housing to the bike, the light goes out completely.

I guess that I am ending up grounding the light twice - once with the ground lead, and the second time by grounding the body of the light assembly itself.

When I try to just ground the body however, leaving the spare wire free, the light is on but doesn't blink.

Any suggestions on how to connect the lights? (Other than trying to rubber mount the bulb inside the signal light housing, or rubber mount the signal light to the bike).

PS - the flasher is new and works. I don't have the original Lucas style signal lights. However, I do have an old big clunky light that looks like it came off a Honda - it's a single lead and works fine (it's bulb is rubber mounted inside the housing).

pkeithkelly said:

The signals I bought are nice and compact,

Click to expand...

Are they LED or standard type bulbs?

pkeithkelly said:

That set up works fine while I'm holding the lights in the air next to the bike to test (flash perfectly), but as soon as I touch the stem of the signal light housing to the bike, the light goes out completely.

Click to expand...

Have you tried connecting the two wires the other way around?

If you have any fitting instructions it is likely that they will only describe how to wire up the signals to a negative ground system?

More info:

- standard bulb - not LED
- yes, tried the wires the other way around
- no, no instructions with the signal lights (EMGO brand)

and tried to ground to an existing ground wire connector in the headlight (works fine, till the flasher stem touches the headlight for mounting)

I have tried every combination possible, and hope there is another option to rubber mounting the signal lights, and thus insulating the housing from the extra grounding effect

anybody solved this problem before ?

I've seen plenty of Commandos with these compact signal lights installed, so I know its doable.

help ...... and thanks

It sounds as though the body of the turn signal is in contact with the wires somewhere inside, since you already have an earth wire this is neither necessary nor desirable, why not use an ohm metre to see whether either of the wires is connected to the body of the signal and then dismantle and insulate the wires inside.

Have you tried taping off (insulating from ground) those "spare" wires?

It seems somehow you're bypassing the flasher - just sending straight current to the lights without running it through the flasher unit that will heat up/cool down and in so doing break/reestablish the power connection thus causing the lights to flash.

I guess that's obvious, and I can't offhand think of how to remedy it.

Good luck. Please let us know if/how you solve the problem. You've got me wondering.

Dave's on to something with that voltmeter.

Turn on the continuity meter and check for continuity between the power input wire and the body of the signal - ideally the threads where it screws into the frame. Continuity? You've got an internal short (or you're checking the ground wire instead of the power input - try the other one).

Have you tried this with all of the lamps, or just one? If just one, try the others - sounds like maybe one of them is shorted internally. Hard to believe they all would be, though.

Still trying to come up with a solution to putting these signal lights on.

Recap -
- flasher works fine
- signal lights (all 4 do the same thing), flash fine when one lead is connected to connector for prev. Lucas light, and other lead is grounded locally - but only if the signal light housing is not touching the bike
- but as soon as the signal light housing touches the bike, the light stops flashing and the bulb goes out, though the flasher continues its "click, click" sound

As you can see from the photos, the signal light socket is touching the housing itself. If I isolate the bulb from touching the metal of its surrounding housing, all works fine.

But is this the only solution? Or am I missing something??

Somebody out there must know the answer. It's not driving me nuts yet, but is getting annoying..... help!

Just to confirm, have you tried installing with the "ground wire" taped up to insulate it so you're not "double-grounding"? Have you checked for continuity between the power input wire and the threads that attach the lamp to the frame?

pkeithkelly said:

As you can see from the photos, the signal light socket is touching the housing itself. If I isolate the bulb from touching the metal of its surrounding housing, all works fine.

Click to expand...

It does seem as if the feed wire could be connected to the ground side of the bulb, which is why it stops working when you ground the stem.

Which suggests to me that the polarity in the signal circuit is reversed?

Are the flasher relay terminals marked?

Oops.....

stupidity is such an embarrassing quality.

I could have sworn I had switched the leads on the lights at least two or three times to test whether they were polarity sensitive, but .....

just did it again, and poof - everything works perfectly.

Sorry for the bother guys. Thanks for the help.

keith

Well, I haven't done anything stupid like that....










...today.


But then, the day is young...!

Glad you figured it out. It's always the simple stuff that kills ya!

pkeithkelly said:

Oops.....

stupidity is such an embarrassing quality.

I could have sworn I had switched the leads on the lights at least two or three times to test whether they were polarity sensitive, but .....

just did it again, and poof - everything works perfectly.

Sorry for the bother guys. Thanks for the help.

keith

Click to expand...

It's not a bother.

What Dave said.

Kinda fun troubleshooting somebody ELSE's problems once in a while. Amazing how much easier it is to think straight when you're not covered in grease and sweat, aggro'd to beat the band, and just dying to apply the BFH to the offending parts...