Coils wired backwards

[Bdogginit]

Hi all,
I noticed that the orange wires that have 12 V are connected to the negative terminals on my coils, while the signal wires from the igniter are attached to positive terminals. The bike runs like this, but if its incorrect then I’d like to get it right. If it is backwards will it damage something and/ or affect the performance. Any advice would be appreciated.

[wymple]

If I recall correctly, the coil doesn't really care about the polarity, but the plugs do. Wiring them backwards requires about 25-30% ? more energy to fire the coils. Not good. This may be an over simplification, but it's the best I can remember.

[Steve]

It does not really matter. wymple suggests that it matters to the plugs, but you have to realize that the coil is in the middle of the high-voltage circuit. That means that on one of the two plugs, the spark will go from the center tip to the extended tang, but the other plug will have the spark go from the tang to the center tip. If you change the polarity of the coil, you will only change which plug fires which way, but one plug will always be opposite the other.

.

[wymple]

Should there not be a reason, then for labeling the pos-neg terminals? Something about large & small windings, or whatever.

[chuck hahn]

Why not just switch them around since youve determined they are backwards? Doesnt really require much debate.

[Brendan W]

Reversed polarity will make a difference but isn't that about the entire machine being positive ground?

[bwringer]

Makes no difference. The terminals on aftermarket coils aren't even marked.

[Gorminrider]

The coils on my four cylinder suzukis are not the same as the coils on my two-cylinder suzukis....

I don't feel like reading a whole lot so I'm going to make all this up: excepting one note I have that says the difference of "wrong" spark polarity is 15%. This might be the most important thing to investigate because it might be "saying" that a four cylinder suzuki has two plugs 15% "below" the other two. How interesting.

The coils on the two-cylinder suzukis are very similar to the standard car coils and on these, ground is shared directly between primary and secondary coils. On these, the spark from the tip is the same polarity. (ground could be + or - if you have an ancient MC ...but that's a digression)

On four cylinder suzukis, the secondary has no connection to ground except through the two plugs each coil fires. On these, the tips have different polarities as the "voltage charge" essentially sparks "upward" through one plug and "downward" through the other. Polarity of the primary makes no difference to this secondary unless there's a steel core with a vestigial magnetism. (That is just something I remember from somewhere)

Sooo, per that vestigial magnetism,oOn second hand coils, changing the polarity has a consequence. Given the steel core is magnetized, changing the polarity, is a bad idea. Again, I dimly recall there's a way to test but somebody who really cares can look it up as fact or fiction.

[Gorminrider]

Sooo, I looked it up. NGK has it that in the "double-ended" or "dual spark" system of the 4 cylinder, one plug will wear cathode, the other the anode. So, buy their fanciest plugs. No suprise there. But I suppose swapping plugs equalizes wear too.

As to "15%" or more "power", applicable to spark polarity this seems to be important to owners of a single-ended coil... that the one way runs better (as in OEM) and that the plug should be designed for the polarity depending if your vehicle is + or - ground....
but Four cylinder double-ended coil owners will have to make do with, "naah, T'ain't true" or , an interesting theory of particle density in the compression cylinder getting the greater spark versus the wasted one!

[metalfab]

Coils from an electronic tech point of view are among the simplest electrical devices, it doesn't care how you feed it power. It just creates a magnetic field that collapses across the secondary coil windings to produce the spark. Which direction the spark is generated from is a pretty mute point. Just to blow your mind a little more electrons flow from negative to positive, the opposite is generally excepted as how it works. In a DC circuit where power jumps a gap the positive side takes more abuse than the negative side. So the positive side is getting showered with electrons, and the negative side is the launch pad. Sort of like with lightening the cloud and ground thing on a lightening strike, the ground fares a little worse because it is being blasted. That might not be a good example, with a lightening strike containing about a billion Joules of energy. A better example might be a TIG welder, if you set the TIG welder to make tungsten electrode positive it overheats, and melts the electrode too easy. If you set the TIG welder to electrode negative and that doesn't happen. That TIG welder example is with significant amperage sometimes hundreds of amps. The plugs are so so over engineered for the amperage flowing through them that it really makes it a non issue.