Don't read into what's not there....
Winterized my Sportster today. When I removed the plugs to spray lub in the cylinders, I noticed the plugs were a little fouled with a sooty carbonh deposit (pretty uniform over the entire plug end). The plug is fine otherwise (it is relatively new) - the electrode is perfectly intact with very little wear.
Searched this forum and didn't fine anything relevant on this, but there is of course tonnes of stuff on the net concerning two strokes and plug fouling (air filter problems, ignition problems, etc). Any advice or am I just looking for a problem that doesn't exist (boat runs fine).
I think you might be reading into something that's not really there. From your description, that's what I'm getting from it anyway.
In my signature below, you'll see a link to my research pages. I have a post on spark plugs you might find interesting. For our enignes, there is a fairly wide range on how our plugs may look. From what your describing, your plugs are fine. The plugs should be a slight brownish in color. Check out the link, there are pix too for you to judge.
Our spark plugs for the 787cc engine, the NGKBR8ES come from the auto parts store pre-gapped to about .031". We need to gap them down to about .021. So, never take for granted that when you get your plugs, they are set correctly. Use a gap gage to be sure.
Reading our plugs. In the language of the plug, the NGK, of course is the maker. The prefix for our plug is BR, which mean the thread diameter is 14 mm and is a resistor plug. The number 8 is our heat range. The lower the number, the hottler the plug. Our suffix, ES signifies the reach of 19mm and uses the standard center fire electrode.
I did some research on the Iridium plug, specifically the IX. These plugs are fairly new and from what I am reading, are a really good replacment for our OEM plugs. These plugs do not change the heat range but will allow a better, more complete burn of our fuel/air mix, which increases horsepower and fuel efficiency. When I say increases horsepower, I'm sure it's not like your gonna feel some kind of big difference. The following is an excerpt that I took from the NGK website on this plug. It's highlighted in bold.
Iridium IX Spark Plugs are the most technologically advanced high performance plugs available. Featuring a 0.6 mm iridium center electrode tip, they offer superior ignitability without sacrificing durability. The tapered ground electrode increases flame kernel expansion, while the superior heat range design is ideally suited to the demands of high performance environments. Specially designed to meet the needs of serious enthusiasts, Iridium IX Spark Plugs offer outstanding acceleration, high fuel efficiency and long life. When you demand the most from your engine, rely on the proven performance of NGK Iridium IX Spark Plugs.
As for the issue of fouling? This can be anything from your carbs not in good sync, a bad plug or gap, a simple carb adjustment or even a bit of oil coming from your rotatary seals.
Remember, we have two ways of reading plugs. One is to judge our plugs from WOT, which allows us to see the performance of the high speed jet and the other will be around idle. Running at idle speed for about 5 minutes then killing the engine, checking the plugs will allow you to see that you might need to open or close the low speed adjustment screw. If you run around 3 or 4K rpm, you'll be in transition. This is when you are drawing fuel from both jets.......
pascalb18, thanks for bringing up the Iridium plugs. I think I'm going to try a set of them this year in my boat. I'll probably continue to run the ES in my GTX and go with the IX in my boat to see if there is any significant change.
Thanks for bringing something new to the forum that might allow us to all get a bit more fuel efficiency out of our 2 stroke motors.........:cheers:
