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Discussion Starter · #1 ·
I'm having a little trouble tracing down my problem. All electrics on the bike work, it's a '74 CB450. Previous owner appears to have bypassed the kill switch. I'm not getting a spark at the plugs. I am getting power to the points, however. Bad coils?
 

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Sensei
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The points getting power means nothing if they aren't opening and closing, or making good contact when they do....Try shorting across the open point with a small screwdriver and then "unshort' and see if the plug fires....
 

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66 has you on the right track. Make sure the point wires are attached correctly as well and not grounding out befor it reaches the breaker.
 

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Sensei
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Ok... try this.... Remove the spark plug "boots' from the heavy wires (they unscrew)....Slide a paper clip down the center of the wire and wind it around the top of the plug... (clip off excess... ) If it now fires, you have bad boots...If not bad coils or plugs........
 

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Discussion Starter · #6 ·
well.. i shortened the wires by clipping about an inch off and then screwing the caps back on. Still nothing, even with known good plugs. I've also tried known good caps that I have from another honda. The only thing that I don't have that I can swap is a pair of 2 cylinder coils. Is is possible to use a single coil from a 4 cyl bike for testing?
 

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Sensei
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Yes and no...(they are internally wound/connected differently).. You can wire one of them to one set of points and check that one side, but the dual lead coils require both HT leads have access to a ground (through the plug gaps), so you'll have to rig an extra plug on the extra wire, sitting on/grounded to the head loosely....DO NOT hook it to the plug in the other cylinder......
 
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