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the bike half around the block started to feel like it was running on three cylinders . so went home threw in 4 new plugs checked them,all had spark , same result. so i figured that its the fuel pump this would be the second one in 48.000 miles . granted i run it close to empty alot . maybe i'm just cooking them but a fuel pump is going cost 350.00 to guess that's it a valid gas but a guess. And on a another weird thing is number one cylinder plug wire i have to un-screw the top of the plug off to put the wire on and the other i leave the on, now that's weird. -----and no the top of number one is not stuck in the wire ----thanks for your help-pete
 

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Checking for a spark by earthing the plug against the motor may give a spark, but under load in a compression chamber is another matter all together.... If there is a short or weakness anywhere in the electrical system it will show up under load when the motor is running. Plug caps can fail, but still present a spark to the plug under a test situation as mentioned above, so a few bucks on some new caps might be money well spent. You could "borrow" some from another motor to check the theory. Also, look for any "arching" where the leads may be shorting out under load. This will present as distinctive marks on the engine casing where the plug leads sit.
I am sure many others way more experienced and knowledgeable than myself will offer their advice also....
 

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Check the resistance of your plug wires with an ohmmeter.
It should be between 6-7K, with the the shorter wires being the lesser value. Or, at least be within 500 Ohms of each other depending on the meter you use.
If one plug wire is much higher or lower, replace it.
Their not cheap at around $55.00 each. You cannot just change the cap or put in some plug wire you pick up from an auto supply store.
Since the K engine fires two plugs at once, Having reasonably matched plug wire resistance is critical to other parts of the electrical system. If there is much variance between plug wire resistance, the very thin internal coil wire that joins a pair of plug wires can burn out and now you have a coil to buy.

Dab some dialectric grease on a cotton swab and liberally put it on the rubber inside of the spark plug cap. This will ease pulling the cap off the spark plug.
 

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flyingkiwi said:
Checking for a spark by earthing the plug against the motor may give a spark, but under load in a compression chamber is another matter all together.... If there is a short or weakness anywhere in the electrical system it will show up under load when the motor is running. Plug caps can fail, but still present a spark to the plug under a test situation as mentioned above, so a few bucks on some new caps might be money well spent. You could "borrow" some from another motor to check the theory. Also, look for any "arching" where the leads may be shorting out under load. This will present as distinctive marks on the engine casing where the plug leads sit.
I am sure many others way more experienced and knowledgeable than myself will offer their advice also....

Mr Kiwi is right there, much different conditions under load, the old "points and condenser" systems were pretty bad for that, but same still applies on electronic systems.
Checking for arcing on plug wires is easier in the dark, and you could go as far as misting the wires/coil with water, any cracks in the wires should show as a spark between the wire and the closest metallic part.
But remember that if you are doing any spark tests with the plugs off the engine, all the wires should have a grounded plug on them, otherwise you may damage the ignition.
And a little here on diagnostics and testing the "Hall Effect Sensor" :thumb: http://www.ibmwr.org/ktech.shtml
 

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As I said Pete, Lots of parting knowledge from folk way more experienced than me....
 

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It the spark plugs that you took out that tell the story of what is happening in that cylinder.
Did you look at them ? was one or more fouled?

The old spark plugs tell you what is wrong.
 
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