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Author Topic: 78 550k no spark / not firing on 1 & 4  (Read 1003 times)

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Offline clark gable

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78 550k no spark / not firing on 1 & 4
« on: February 20, 2012, 07:04:19 PM »
1 & 4 were not heating up. I checked the plugs, they were suspect and i had repalcements so I swapped them. Still nothing.

I placed the 1&4 plugs against a ground source to check for a visible spark when starting the bike, however there was no spark at all. I put 2&3 through the same test and they sparked well.

Any ideas? I doubt it's the carbs, everything seems in order there.

Thanks
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Offline cbr954

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Re: 78 550k no spark / not firing on 1 & 4
« Reply #1 on: February 20, 2012, 07:06:08 PM »
1 and 4 share same coil and points.  Swap coils and see if the problem follows the coil.
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Offline clark gable

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Re: 78 550k no spark / not firing on 1 & 4
« Reply #2 on: February 20, 2012, 07:25:58 PM »
Thanks. I will try that tomorrow hopefully. Could it also be that the 2/3 points arent meeting properly/sparking at the plate?
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Offline Bankerdanny

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Re: 78 550k no spark / not firing on 1 & 4
« Reply #3 on: February 21, 2012, 09:33:51 AM »
When my bike did this it was because the wire that runs from the condenser to the points had come loose. It's held in place by a very small nut. Tightened it up and never had another problem.
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Offline Deltarider

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Re: 78 550k no spark / not firing on 1 & 4
« Reply #4 on: February 21, 2012, 09:55:45 AM »
Quote
When my bike did this it was because the wire that runs from the condenser to the points had come loose. It's held in place by a very small nut. Tightened it up and never had another problem.
Yes, but make sure you do it correctly and avoid making ground to the baseplate! Sometimes this ground contact occurs intermittent which makes it harder to diagnose.
« Last Edit: February 21, 2012, 12:41:51 PM by Deltarider »
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Offline chrima

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Re: 78 550k no spark / not firing on 1 & 4
« Reply #5 on: February 21, 2012, 12:47:35 PM »
You can easily switch coils by unplugging the blue and yellow wires that run from the points. There should be a spot near the battery where they plug in to the harness. Just make sure you don't actually start the bike. Just rotate slowly with the kick starter.

I had this problem twice. First time it was the points, second time a loose wire connection at the coil.
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Offline clark gable

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Re: 78 550k no spark / not firing on 1 & 4
« Reply #6 on: February 26, 2012, 10:56:54 AM »
All it was is that the 1/4 points weren't making contact. Quick adjustment and she's good to go. Thanks fellas.
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