Fitting a DRL headlight, Help!

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I have a DRL headlight i would like to fit to my negative earth Commando. Im sure people will say this cant be done but im sure it can. I have got everything working individually but cant figure out how to get it wired correctly. Can anyone help with a wiring diagram before i pull all the hair i have left out? Many thanks.
 
Sorry i dont know how to put a picture here but it is a full replacement headlight with Large LEDs and a DRL ring round the outside. It comes with a plug which will fit straight into the Norton headlight fitting but clearly wont work wired as it is. Basically which whire goes where to get it working as it should?
 
Sorry i dont know how to put a picture here but it is a full replacement headlight with Large LEDs and a DRL ring round the outside. It comes with a plug which will fit straight into the Norton headlight fitting but clearly wont work wired as it is. Basically which whire goes where to get it working as it should?
A tutorial written by one of our members on posting images. And welcome to the club.
Fitting a DRL headlight, Help!
 
Can you give us a link perhaps to the light that you have? And what year Norton are you mounting it to?
 
Its going on a 1973 MK2A The Headlight is E bay number 133542724820 if i am allowed to do this. Sorry im a bit of a Luddite with computers.
 
It looks like connecting your bike's pilot light (brown/green) wire in the headlight shell to the blue wire on the new headlight would work. That'll make the halo ring your DRL.

edit: This assumes however that that light works with positive earth.
 
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@maylar the OP states that his bike is wired negative earth, so he should be good to go!


If you want the DRL to come on with the pilot light, just wire the red cable of your new lamp to the brown/green of the pilot light/speedo/tacho backlight

Alternatively, if you want it to come on when the ignition is hot (so to work independently of the rest of the lights), just wire the red cable of your new lamp to the white that goes to the ignition warning light
 
EEEK i just realised i put negative earth. The Bike is Positive earth, this is the problem. Sorry for the confusion folks, i told you i was no good with computers :)
 
That light isn't gonna work with positive earth. Sorry bud.
 
Maylar, this is what i feared. Just how much work is involved converting to Neg Earth and is there a rundown of whats needed and involved on this site? Or i could fit it to my BMW Rnine T.......
 
EEEK i just realised i put negative earth. The Bike is Positive earth, this is the problem. Sorry for the confusion folks, i told you i was no good with computers :)
Very easy to convert bike to Negative Earth and you don't need a computer to do it:D
 
How difficult it is depends on what your configuration is.
What kind of charging system do you have (voltage regulator)?
What kind of ignition?
 
I have converted negative ground components to positive ground using relays. This only works it the item does not have a chassis ground. My combo voltmeter/thermometer/clock is wired that way as an example.

I would argue that converting an existing running bike to negative ground is not a straight forward job. I have looked at doing it a few times, and it just has never been worth the headache.... at least to me...

If I was rebuilding a relatively stock bike from the frame up, that would be a different story....
 
Thanks Olympus, could you elaborate on that. Details? Thanks.
I'm surprised that there isn't a tutorial (or I haven't found one) that details converting to negative earth. I've done it myself, but I'm very electrically capable, so depending on your electrical skill set it might be more difficult for you. However, basically these are the things that need to change:

1) Your charging system. With aftermarket rectifier/regulator that's just a matter of swapping 2 wires. With the stock bridge rectifier / zener diode setup it means swapping the +/- terminals on the rectifier and installing a new zener diode that is polarized for negative earth. Fortunately negative ground is the "standard" zener polarity (case is negative) and the zeners are available from electronics suppliers like Mouser and DigiKey. The part number would be 1N3313B which is a 14 volt 5% 50 watt stud rectifier. You'd have to solder a 16 ga. wire with a 1/4" male spade to the cathode terminal, and the nut will be 1/4-28 NF instead of the 1/4-26 cycle thread on the Lucas zener.

https://www.newark.com/solid-state/1n3313b/zener-diode-50w-14v-do-5/dp/56J9299?ost=1n3313b

2) Your electronic ignition. You said in a PM that you have a Pazon. That and the ignition coils need to be rewired. I'm sure the installation instructions would cover that.
3) The battery. The +/- need to be swapped. That's the last step.

The only downside to this procedure is that you have to remember that all the red wires in your harness are now NEGATIVE.

I did it on my own bike some 10 years ago to take advantage of standard automotive LED's in the blinkers and tail light. That was before non-polarized LED's were available. No regrets.
 
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