TOPIC:

This 4 ohm coil should function okay.

www.z1enterprises.com/ItemDetails.aspx?i...zuki&item=EM24-72451

Note 90mm mount spacing.

If in doubt, could give the folks at Z1E a call.

Good Fortune!

loudhvx wrote: The positive, primary terminal should be on the north side of the bike (negative terminal - south).

The positive, secondary wire should go to the plug that fires first (negative wire - second).

This was meant for Patton. Guess it wasn't funny.

Am having difficulty in understanding:

The concept of one plug firing before the other in a dual output coil, because of thinking -- at least until now -- that both plugs in the secondary loop fire simultaneously;

How polarity of the primary winding (when grounded) influences its interrelationship with the secondary winding in creating the magnetic field that collapses upon un-grounding of the primary winding and causes high tension voltage throughout the secondary loop;

The reasons why polarities of primary and secondary windings are prescribed in some dual output coil models, but not in others.


In the diagram, the polarities of the primary winding and secondary winding appear to be reversed, with the primary positive being on top and the positive plug wire being on bottom.


Good Fortune!

loudhvx wrote:

loudhvx wrote: The positive, primary terminal should be on the north side of the bike (negative terminal - south).

The positive, secondary wire should go to the plug that fires first (negative wire - second).

This was meant for Patton. Guess it wasn't funny.

It is now. Got me!

Good Fortune!

Kidding aside, I don't really see a reason for any polarity markings on our Kz ignition coils.

The coil is just basically a transformer, and transformers are often marked with polarity, but not for voltage polarity, since they are often running on pure AC there is no voltage polarity, but the marks are for phase polarity so that if you apply a positive signal to one side, you will then get a positive signal out of the other side. So maybe the manufacturer also makes other generic transformers and they are in the habit of marking phase polarity, so added the marks to the ignition coil for consistency?

The plugs do exhibit differences depending on which way the spark is travelling (from insulated tip to the ground electrode, or reverese). One may have more metal wearing away from the tip, and the other may be wearing away more at the ground electrode. But with waste spark, one plug will be firing forward, and the other reverse, and they both seem to fire the cylinder equally well, so it apparently doesn't matter much.

loudhvx wrote: Kidding aside, I don't really see a reason for any polarity markings on our Kz ignition coils..

Could it be that the polarity matters when using the Kawasaki Electrotester?
Or maybe it just simplifies the testing procedure for the Kaw mechanics?

From the 81 KZ650 Kawasaki factory service manual.

Ahh, never seen that before. But yes, if the tester is injecting some sort of signal, polarity would matter a lot.

The FSMs for Z1-KZ900 and KZ1000 '77-'79 have similar illustrations advising Connect the coil to the tester according to the directions with the tester.

Neither illustration shows any polarity markings on the coil.

The test is supposed to confirm the coil's ability to produce at least a 7 mm spark.

Here are the illustrations from the FSMs:







Here's the page from '77-'79 KZ1000 FSM:



Good Fortune!

Patton wrote: This 4 ohm coil should function okay.

www.z1enterprises.com/ItemDetails.aspx?i...zuki&item=EM24-72451

Note 90mm mount spacing.

If in doubt, could give the folks at Z1E a call.

Good Fortune!

That coil has been out of stock for a year or more. I have not found it anywhere, I don't think it is sold anymore. Too bad, I am running one and it is a really good coil.

loudhvx wrote: Kidding aside, I don't really see a reason for any polarity markings on our Kz ignition coils.

The coil is just basically a transformer.

The only reason I could think of is if the physical layout inside is set up to put the "ground" side of the primary winding closer to the ground frame and the "pos" end of the winding that pops to about 400V when the points open is farther away to minimize danger of arcing. Probably doesn't matter.

Emgo --- KAWASAKI KZ400 Z1 KZ650 KZ750 KZ900 4 OHM IGNITION COIL W/ PLUG CAPS
$55 total w/ NGK caps. eebbaayy seller is georgefix. He also sells them in pairs for $105.

That's even stranger. It appears all of the test fixture connections are marked with polarity, but why mark the fixture with polarity if the device under test has no polarity markings?

One would then have to conclude that none of the polarity matters on either the coil or the test fixture, which means Kawasaki is just messing with people.