Author Topic: Measuring ohms on sparkplug caps.  (Read 27733 times)

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Offline 1crustycb

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Re: Measuring ohms on sparkplug caps.
« Reply #25 on: February 08, 2021, 05:32:16 pm »
As I was checking this link out, I noticed that it was said that the original honda sparkplug wires were stranded copper, and that the carbon cored wires ( automotive style ) are not recommended. What about - and please don't laugh - furnace ignition wires? It can be bought in bulk, it is stranded copper wire ( 18-24 gauge ) the jacketing is high temp silicon ( 428 degrees fahrenheit  ) it is rated to carry 25kV dc. I do not have any in use at this time, but years ago we used some to make plug wires on Datsun 260Z. A radio was useless in the car for anything but listening to the ignition pop. I have no " real-world " measurements as to the resistance of the wires, but I would think that the resistance would be low in the lengths that would be used for plug wires on a motorcycle. This is just a question, and I am not offering this as a solution to plug wire issues. what do you think?

Offline HondaMan

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Re: Measuring ohms on sparkplug caps.
« Reply #26 on: February 12, 2021, 06:07:03 pm »
The OEM plug wires are molded into the coils, so they can't be changed. A few 3-ohm coils out there will let you install your own wires, but those coils will drain all the power these bikes can muster, so they are a bad choice for them. The 750 can just barely hold the battery charge up of driven mosotly on the hiway with those coils, but other than that, don't use those on these bikes, it won't go well.

I've seen a [silly] 'wire splicer' from some Japanese maker that lets you try to splice in new wires: these don't work well in humid climes, though. In desert areas they will work for a while.

Honda still sells the coils as a full unit, brackets and all, about $150 for the set. You can get some drop-in replacements by Sakura (PartsNmore #17-6823) If you don't mind mis-matching the wire colors, or else swapping the bullet connectors so they fit in correctly. The Dyna 5-ohm coils work well, if expensive, and seem to last a long time. Just use some resistor plug caps with any of these for best results.
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Offline Funkenstein

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Re: Measuring ohms on sparkplug caps.
« Reply #27 on: April 03, 2021, 12:59:12 pm »
Just used this page to diagnose my bike. Hopefully this fixes my rough running issues. Thanks, Hondaman!!!
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