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Running on 1 Cyl

965 Views 5 Replies 2 Participants Last post by  V-FORE
Bike was running very weak
so I have realized that the right cyl was not working(holding on to the exhaust told me that) I changed out the cdi box, since I had another one & no change. I am getting a very weak spark(holding on to the plug while cranking) when I checked the other side(much stronger spark) so I have changed the wires going into the coils with no change so I have come to the conclusion that I need a coil
If there is something I have left out let me know. Next question does anybody have some spares that they would like to sell??? I figure that I might as well change them as a set.

Thanks in advance

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Gary, when you swapped the coil wires, exactly what did you do? Just swapping the input wires would only work to see if there was any spark with the plugs out. The bike wouldn't run, with the spark 180 out of time. But if you also swapped the plug leads, and hooked them back up, then the left side wouldn't fire if the coil was bad.

Coils can and do go bad. They are usually cracked and allow moisture in. Especially in the great Northwest. Another culprit could be your plug caps. These will unscrew from the cable end and can be taken apart for cleaning and service. Make sure that the resistor is intact, and that the cap has no cracks in it. You should read approx 4-5000k ohms resistance thru the cap from the wire side to the plug side. Resistors can be eliminated using a short piece of brass or aluminum rod.

Coils should be available off E-bay used and you stand a good chance of getting usable ones as they seem to last fairly well. I think Shep on this forum has leads on new coils, and a few others have posted about getting new ones. You do need to get the coils for CDI ignition, rather than a TI for them to work properly.
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Glad to hear you are back in business, Gary. Do you think it was the bad connection that caused the problem? Or the second CDI droping out one side?
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