C5 spark plug gap ?

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ekvh

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Curious what you guys with C5 gap your plugs at. C5 recommends a smaller gap for plugs. I had NGK dpr8ea plugs. They were showing signs of being a tad rich at lower rpm. I decided to go with dpr7ea plugs and left them at around 0.030". They were still sooty at idle. Today I decided to close this gap to 0.025". What a difference in idle quality!

Now mine probably has more compression than some and needs to bridge the gap. It was too cool and too late to ride it tonight, but I look forward to getting out again on it.

Love to hear what others have found works for theirs.
 
C5 can use the stock gap very effectively and a bit larger if chosen. Coils are more than potent enough to bridge some very large gaps. If I recall my conversations with Paul correctly.
 
I like to keep them at the lower end of the recommended gap. When it was in the 1100, I had them set at .025. Now that I have it in the 1200 I have them gapped at .032.
 
We recommend 0.28-0.32" to start with. On high compression engines we often drop the gap to 0.020" or on LP (propane) we run 0.015-0.018" gap.

If you wish to run a larger gap on high compression but have fouling issues I suggest making small adjustments to the saturation map if you have access to a programmer. With the new MC2 coils this is a bit dangerous to play with and I would appreciate a call first to discuss.

Changing heat ranges might help but first you should inspect the heat line on the ground strap to verify temperature.
If the color line is correct I would not change plug heat ranges.
 

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Mine is put away for the winter, but I did have a few chances to ride and one day was almost 70f. The electrode's heat line was in the middle, but running it harder than usual for ten miles pushed the line towards the base more than the end. So my conclusion is that 7's might be okay with cooler temps, it's probably too much for summer temps. I last had them set right at 0.028 and it seemed to be able to pull without a miss to 9k+. Hoping to pick up a cable to change the curves some next year.
 
[url=https://www.classicgoldwings.com/forum/viewtopic.php?p=184157#p184157:1ij3i0zk said:
ekvh » Thu Nov 24, 2016 5:37 pm[/url]":1ij3i0zk]
Mine is put away for the winter, but I did have a few chances to ride and one day was almost 70f. The electrode's heat line was in the middle, but running it harder than usual for ten miles pushed the line towards the base more than the end. So my conclusion is that 7's might be okay with cooler temps, it's probably too much for summer temps. I last had them set right at 0.028 and it seemed to be able to pull without a miss to 9k+. Hoping to pick up a cable to change the curves some next year.

I'm in Western Wisconsin and Iowa all the time. We could always meet and change maps. It only takes a few minutes.
 
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