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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.
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.

