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Everywhere I look online I see the same 8 photos of sample sparkplugs, apparently from NGK if I am not mistaken, and none of them look like my plugs, which both look completely different but somewhat healthy, I think.
The bike is a '94 with high-comps and FCR41's. Stock jetting, EMR needles on the middle clip. So far as I can tell, stock timing with a touch of detonation under heaviest loads on the hottest days, but none otherwise. It does have an oil consumption issue, about 1 qt every 1k miles. Compression looks good, both cylinders in the 210 range and within a few points of each other.
My Kokusan igniters popped a few years ago and I replaced them with some Electrosport modules. Using these the front cylinder looked black, sooty and wet and the rear cylinder looked chalky. I assumed that the front was my problem cylinder, but I consistently still had issues with the bike. I recall Brad Black, in several instances, blaming the Electrosport igniters for fouling plugs and running lousy.
Recently I came across a pair of DP igniters, the 7.900 version, and swapped them out, with good results. Much better running, better starting, and cleaner less fouled plugs. Now the front looks good I think, and the back looks like the problem cylinder, but I'm no expert and open to some opinions.
These are the same plugs I had been using, pulled and cleaned with a wire brush some 200 miles ago. This is all from the DP igniters. Plugs are photographed in front of their respective cylinders.
Thank you all in advance for your input.
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The bike is a '94 with high-comps and FCR41's. Stock jetting, EMR needles on the middle clip. So far as I can tell, stock timing with a touch of detonation under heaviest loads on the hottest days, but none otherwise. It does have an oil consumption issue, about 1 qt every 1k miles. Compression looks good, both cylinders in the 210 range and within a few points of each other.
My Kokusan igniters popped a few years ago and I replaced them with some Electrosport modules. Using these the front cylinder looked black, sooty and wet and the rear cylinder looked chalky. I assumed that the front was my problem cylinder, but I consistently still had issues with the bike. I recall Brad Black, in several instances, blaming the Electrosport igniters for fouling plugs and running lousy.
Recently I came across a pair of DP igniters, the 7.900 version, and swapped them out, with good results. Much better running, better starting, and cleaner less fouled plugs. Now the front looks good I think, and the back looks like the problem cylinder, but I'm no expert and open to some opinions.
These are the same plugs I had been using, pulled and cleaned with a wire brush some 200 miles ago. This is all from the DP igniters. Plugs are photographed in front of their respective cylinders.
Thank you all in advance for your input.
