positive earth???? what the???

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Dec 5, 2007
Just reading up the installaiton manual of my new Pazon electornicignition. it says positive earth is standard and to earth to the positive terminal??/is this correct? how can you have a positive earth? i charge the battery by putting the red on the positive and the black on the negitive so what is that? i always assume negative was ground .i.e frame ,chassis, is this a misprint or am i about to learn something
The standard polarity of the Commando electrical system, and indeed a lot of British bikes is Positive Earth so the battery Positive (+) side is wired to the frame (Earth or Ground).

Many modern vehicle electrical systems are Negative Earth, where the battery Negative side is wired to Earth.

So trace where the battery + & - wires go?

If the battery Positive side wire does go to the frame then follow the Pazon instructions for Positive Earth connection.
For a real edumacation consider what needs to take place to carry off a jump from another vehicular. Without blown up battery's.
All of the older British motorcycles and cars that I have come across are Positive Earth. This is the reverse to North American vehicles and is done in order to allow the electrons to flow the proper way such that driving on the wrong (left hand) side of the road is possible.

Seriously, it's no big deal provided you take note of the polarity and make yourself think in reverse with all things electrical on the bike.
I switched one of my Vincents from it's original positive earth setup to negative earth so that I could use a new negative earth only charging system. It was no big deal, I just hooked the battery up the other way round.
Can't comment on switching the Norton, mine is still positive earth and there may be some aspects of the standard electrical (zener diodes, starting capacitor?) which need to remain positive earth. Unless you have some major piece of electrical equipment to install and this equipment is negative earth only, there is no need to change to negative earth.
In addition to being able to drive on the left-hand side of the road, positive ground (earth) DC circuits are less susceptible to corrosion.
I'm thinking of changing to a L.E.D. tailight. This would require a negative ground, as far as I know. Some of the guys have mentioned running L.E.Ds for intrumentation lighting. I don't know if they have + or - ground. I do know diodes are polarity sensitive.

As for charging a battery, it cares not which terminal is grounded, just that the + to + and - to - connections are made. Also, when I use a Battery Tender©, I disconnect the zener diode. The charger never goes into float mode with the zener connected.

Wasn't positive earth for better right hand cornering? Hence the negative earth for the U.S. flat trackers
Yes, counter clockwise racing, especially on dirt tracks, required positive ground and a right-hand shifter. AND corrosion resistance - those were the drivers for the positive ground electrical systems.
Jim - Commonly available LED bulbs are normally negative earth as this is the way automotive electrical systems are now. There are some specialists who manufacture +ve kits for brit bikes and I have one on mine to give the old Lucas charging system an easier life in winter. It works well. You can see the one I've got here: http://www.norbsa02.freeuk.com/goffyleds.htm
They turn up on eBay from time to time too. Cheers, Nick
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