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I ordered and installed 2 of these back in December....from Spark Plugs.com or ngk.com

NGK 95399 SILMAR9B9 Laser Iridium Plug - Item# NGK95399

I have ran those for about 1,000 miles or more now
any difference running these iridium plugs? would you recommend buying these instead of the stock ones?
 

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Can you elaborate on this?

You may or may not already know this. But some spark plugs come with a round head terminal nut that is screwed onto the threaded end and needs to be removed before install so the coil snaps onto it...

View attachment 5003
what spark plug wrench did you use? i don't know which one to buy because of the length.
 

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any difference running these iridium plugs? would you recommend buying these instead of the stock ones?
I’ll chime in on this one. I noticed no performance gain on the butt dyno. Where I did notice improvement is them holding up to my excessively rich fuel map without needing to be pulled and cleaned constantly. I don’t think anyone has pushed the limits of the ignition system where this is relevant yet, but there is also something to be said about using a higher reliability plug, even in daily driving conditions.
 

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any difference running these iridium plugs? would you recommend buying these instead of the stock ones?
yes I also second rkturbo's reply, as well as what he said, they should operate at peak performance for a much longer time than the standard plugs( so rather than 10k miles lasting 20k, 30k or however long...I know in your average street car they are 100k mile plugs, so I would probably say doubling the average plugs, so 20-25k seems right...could be longer)
 

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Note that the spark jumps from the sharp edge of the electrode. As the plugs are used, that edge breaks down and become more rounded, reducing their efficiency. Iridium is a stronger (and more expensive) metal, which does a better job of holding that sharp edge. Since it wears less, the electrode can be smaller, resulting in the spark being slightly more consistently located. That tiny improvement probably won't really be noticeable in daily usage though.

If you're not in a special situation where you need plugs that are stronger than stock (like the rich mapping described above), the real gains would come from being able to open up the plug gap to better ignite the mixture. Since the spark is a little more focused with the smaller iridium electrode, it can handle opening up a bit more. When I added CoPs to my 500, I switched to iridium plugs and increased the gap a bit (.024-.028" stock, I opened them up to .032"). I didn't really notice any gains, but as far as I could tell unscientifically, it still ran just as well with the larger gap (implying that I didn't hurt anything with the change). According to NGK's specs on the product pages, the 92222 LMAR9G is .031" and the 95399 SILMAR9B9 is .035" so you're getting a bit of that inherently, though you should still check/gap the plugs to match the application.

With only 2 plugs and the relatively small number of miles that get put on many bikes, this is probably an upgrade that's worth the extra few bucks over regular plugs. I wouldn't expect a whole lot from it, but it may run a tad smoother, and they should last longer if nothing else.
 

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I ordered and installed 2 of these back in December....from Spark Plugs.com or ngk.com

NGK 95399 SILMAR9B9 Laser Iridium Plug - Item# NGK95399

I have ran those for about 1,000 miles or more now
did you re gap these at all, or go with factory gapping?
 
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