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Registered
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16 Posts
Discussion Starter #1
Hi there,

So I current have a problem with my bike where the rear cylinder will not fire. I did a simple spark test and found that both plugs on the rear cylinder are not sparking though the front works fine. Additionally if the spark plugs are swapped and put on the wires from the front they work fine.

So I've done a fair bit of testing but am currently stuck so hopefully someone might have some advice fore me.

First of all this is what I've done.

-From my readings it seems like the problem must be either:
---A lose connector
---A pickup coil issue
---An ignition control unit issue
---Or a ignition coil issue

I've checked continuition on the plugs and the wireing seems to be fine so I've ruled out a lose connector or a broken wire

I've done the resistance test on the pickup coil and it is within spec according to the clymer manual

I've done the resistance test on the ignition control until and there maybe a bit of an issue here. What I am seeing so far is that the clymer manual specifies different resistances depending on the polarity of how you hook up the test probe and yet I get the same reading in both directions (though I'm not sure if this is because I don't have the kawasaki tester to do the tests with). Additionally, the readings I get are within spec for one of the possible polarities.

I've done the resistance test on the ignition coils and they are within spec.

Anyway if anyone whose run into an issue with the ignition system has any advice that would be great as I don't really know where go from here. I was thinking about just replacing the Ignition Control Unit, then if that doesn't work the ignition coil then if that fails replacing the pickup coils though I'd like to hear back before I start ordering up parts.

Regards,

Andre
 

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Old Truck Junkie
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4,133 Posts
From what you said, you have checked the wires that connect to the coil. I had a problem after washing the bike once. The wires had gotten wet and a bit of corrotion kept it from firing.
 

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Linkmeister Supreme
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7,960 Posts
Andre, your diagnosis procedure sounds pretty thorough to me.

One question for you. Does the rear ignition coil not fire either cold or warmed up to room temperature of 20*C (68*F)?
One member had a similar problem where his rear coil fired cold, but cut out as the engine warmed up and the resistance increased.

You might try swapping the position of the front and rear ignition coils to confirm or eliminate it as the problem.
If the front cylinder continues to fire, you know the coils themselves are not faulty.

Also try electronic spray cleaner on both male and female sides of the ignition control electrical connectors, and physically push them together and apart 2 or 3 times to dislodge any of the possible corrosion that niterider mentioned.

If that doesn`t clear up the non-firing issue, I think the next step is getting another ignition control unit.:hitanykey
 

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Registered
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16 Posts
Discussion Starter #4
Ya, that is a good point about swapping the coil packs. I'll give that a shot tonight. Unfortunately the electrical cleaner and reconnecting didn't fix it.
 

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Premium Member
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369 Posts
Perhaps easier than swapping the coils is to swap the green and black wires in the 6 pin connector of the IC igniter. The bike won't start, but you just need to check for spark in the front and rear cylinders.

If still spark in the front plugs but not the rear, the problem is somewhere between the IC igniter and the plugs (coil, plug wires, plug caps).

If there now is spark in the rear plugs but not the front, the problem is the rear pickup coil or the IC igniter itself.
 
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