plug fouling problem unsolved

EIX are easier to foul than ES plugs.
The fouling is crud building up on the tip stopping a useful spark from jumping the gap, an EIX has a very narrow tip, an ES has a fat tip, ES are harder to foul comparatively, but EIX give a stronger more consistent spark.
 
Fouling is a leakage current path across the surface of the insulator to the plug body, bypassing the gap. Spark occurs at the point of least resistance, a very small area of the electrode, usually on a sharp edge. A high grade plug with a platinum fine wire electrode would be more resistant to fouling for two reasons: Less area around the center electrode wire to form a parallel path, and a less resistance in the electrode wire itself. In practice this is probably not that big a difference. If the bike fouls one type it will likely foul the other. You can't fix that problem with a plug. I'm running the same basic cheapo BR8ES all year and its fine.
 
EIX is iridium not platinum, and even in cars iridium plugs foul up much easier than regular plugs. A fine tip non iridium plug is an -EG plug, which I havent fouled ever:p
 
Irridium, platinum, doesn't matter. I used platinum as an example but the point was the only difference is electrical resistance and resistance to errosion at high temps. The failure mode of a fouled plug is a short or decreased resistance, not insulation or increased resistance of the gap. If there is a current path around the electrodes, you won't get a spark no matter how large or small the area of the center electrode is. I never fouled ANY plug in a GasGas that was jetted decent, and I do a fair amount of technical trail riding plus riding with my kids, with a 36:1 mix. If you think the EIX plugs foul faster, perhaps the heat transfer is not exactly the same as a standard plug even for the same listed range (8, 9, etc). I don't think it makes much difference, and if your ignition is in good shape you should be able to run any plug with good results.

Cars? When was the last time you fouled a plug in a car?:confused: Platinum electrode plugs in cars here for the last ten years or so go 100K without a thought.
 
Yes I do but hey If no one wants to listen I don't care. Let them chase there tail been there done that. Everyone told me both times not the cdi and like an idoit i listened twice and hunted for answer but both times plugging in a new cdi fixed it. Both times to different bikes. Get a CDI.
 
I thought it was relevant to a thread about fouling plugs :confused:

As for cars, about 6 years ago, all 6 on our track car, $240 bye bye. Did them all on start up, replaced them with platinum and never a problem since. (Now I understand this is off topic, the other stuff wasn't really)
 
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Hey Silver,

I got an 2005 EC250 and I have changed a few jets and needles and still have the issue that you described as a rev limiter, it won't idle either. Where can I get a CDI from? I am in Australia.

Thanks
Tim
 
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