TOPIC:

After getting crappy measurements on the secondary of my coils, I decided to try the new Emgo Coils Z1 had on their website.

As you can see below, they are a drop-in replacement for the factory KZ650 coils, identical in shape and size!

New NGK spark plug caps, some cutting and screwing, and I had new coils, plug wires, and plug caps in about an hour!


TIP: Really check your old coils properly. My Factory Service Manual never said anything about removing the old plug caps to check the coils themselves.

Turns out my old coils are still good, with about 4.5ohms on the primary and 14.5kohm on the secondary. The ends of the plug wires were badly corroded, and a couple plug caps were too.

Fortunately/Unfortunately the plug wires had already been chopped before for a cap replacement, and I don't think I could have cut them again and had the wires reach the new plug caps.


Long story short - if your secondary readings are >30kohm up to infinity, check your plug caps and connections before replacing perfectly good coils. They are far more likely to fail than the coils themselves.

Haven't tried these plug wire splicers, but they are available from Z1E.

plug wire splicer

Also started getting inconsistent widely varying ohm readings on the old original plastic plug caps when tested on the bench while disconnected from the wires.

Smashed one apart for the fun of it to check what was inside and remember seeing a small chip similar to a little chunk of #2 pencil lead. Guessing it served as an in-line resistor.

Anyhow, was happy to avoid further issues with cap/wire connections, so installed new Dyna wire core plug wires which come with the caps already attached.

And couldn't care less about non-resistor wires/caps causing audio/radio antenna signal interference.

Thanks guys for the info, this could be very useful in the future.I think I would of bought new coils before thinking of this.

I agree with non-resistor interference. I don't have a radio anyway hahahah. My friend's Dad used to come out and yell at me for wiping out their TV (they didnt have cable). Anyway, I soldered a set of Accel wires onto my factory ones, cut them down to about 4 inches. Worked fine. If your wires are no good all the way to the coils (unlikely) then you would probably have no choice but to replace the whole thing. Either way those Emgo coils are plenty cheap enough and nice and brandy new so why not?? Now you can splice some new wires onto the old ones and keep them as spares. Could even carry one under the seat just in case.

Ron

Thise are nice looking coils for someone whio wants to look fairly stock. How much?

When you check secondary resistance, you should always remove the plug caps to do this. Many of the plug caps are resistor caps - they have a 5k resistor built in - so that alone will polute the readings.

With these older coils, the plug wires are indeed the source for many of the failures - not only the contact point with the plug cap, but all down the wire internally.

Sometimes all you need to do is trim 1/4" off the end of the plug wires to get back to good core. It's worth doing before buying.

I've disected a few wires on old coils and you get deteriation of the core and arcing in those area.

ok, not to sound like an idiot, but how do you test the coils?

boomboom45 wrote:

ok, not to sound like an idiot, but how do you test the coils?

LOL!!! Not an idiot! Someone asked a really smart man how he got to know so much. He answered that it was because he wasn't afraid to ask when he didn't know!
Here, bookmark this:
dansmc.com/MC_repaircourse.htm
scroll down to electrical/electrical testing, and towards the bottom of that page he'll tell you about checking a coil. I think your coil should have 3-4 ohms across the primary.

Do you have the part number for the EMGO coils? Are they a 4 olm coil?

Thanks!

Part # 24-72451
I called a dealer, not Emgo directly and they say these are for 1979 and up. Anyone know what changed in 1979?

Ignition Coil for Classic
Suzuki GS and
Kawasaki KZ/
For Suzuki
Fits:Early GS1000, 550, 750, 1000
Models with points ignition
Replaces OEM 33410-45012
Kawasaki
Fits: KZ400D, KZ400 Twins KZ750B/
Twins,
KZ 650 B1-B3, C1-C3,D1-D3, H1,
Z1/Z1A/Z1B,KZ900/KZ1000.
with points ignition models

Don't you mean 1979 and older?
The models you list are all 1979 and older.

Electronic ignition started in 1980, for the KZ1000 and they use different coils.

Post edited by: loudhvx, at: 2007/07/17 13:44

That makes more sense. The parts guy just said 1979 and up. He must have been mistaken. I'm am going to try a pair. I would say they are an OEM replacement which should work fine.

Post edited by: Spyder, at: 2007/07/18 13:41