Since you're enjoying this one with your popcorn, Todd, I figured I'd reply to you... For no other reason than for your enjoyment. What I'll post below isn't a response to you... It's a general response to several other people who have been "piling on".
1) Okay, so I found the cr9EHIX-9 "recommendation" in two other older threads on this forum. The riders using these plugs report the plugs look fine after many miles of riding. So, if that is the case, it SUGGESTS (doesn't prove) that these plugs will be fine and not lead to extra carbon buildup.
2) I am NOT an engine engineer, nor do I have any capability of running several different motors to run tests comparing spark plugs with one another, but from what I have been reading and from speaking with auto mechanics, it seems the case that spark plug inspection is a simple and fairly effective way to determine if one's engine is running lean, rich, or within the sweet spot range.
3) Whether my "pro" installed iridium plugs are counterfeit or not, they are the wrong fitment. I looked on NGK's site for codes, and the "H" (which I thought meant "Honda"), actually means "half thread". Hence, the extra "collar" in lieu of the full 19mm thread length. The member(s) who insist that the "pros" put in the right plug seem to continually avoid this point, and the fact that the plugs the "pros" installed are NOT even the correct code plugs. As DDuelin posted in a photo of the manual, the Honda specified plugs are clearly CR7EH-9 or CR8EH-9. The plugs the "pros" installed are CR7EIX. "IX" is the NGK code for iridium. There is no "H" present in the plugs the "pros" installed, which is clearly specified by Honda. The plugs, while having an acceptable heat value, have a different shape and fitment. Logically, this will have some effect on the performance of the plugs.
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4) Continuing from #3, both the specified NGK and Denso plugs do not have full 19mm length threads. They both have a "collar" - a thicker non-threaded portion of the "barrel" of the spark plug that protrudes below the sealing gasket. Logically, there is a damn good reason that Honda specifies these shaped plugs. Why...? I dunno... Perhaps the "collar" adds more contact with the engine casing, keeping the plug body warmer so that it can reach the proper minimum 500 degree Celcius carbon burning temperature.
5) Continuing from numbers 1 and 2 above, it is consistently reported that the smaller iridium tip produces a "more powerful" spark (for lack of better description). A more powerful spark will help with complete combustion. And this could logically follow then that even a slightly lower heat range iridium plug could still produce a very satisfactory ignition leading to complete combustion. Again, I am no engine engineer, and I cannot confirm or deny the "quality" of iridium sparks versus copper sparks.
6) At any rate, life is an exploration... Spark plugs, even iridium plugs, can be purchased for about the price of a tank of gas. And I can change them myself. I've ordered some Denso iridium plugs (heat value of 8) and am going to order another set of NGK's (heat value 8) that have the CRITICALLY important shortened threads and included "collar". My bike didn't blow up with the wrong-fitment cr7eix NGK's, although the plugs show definite signs of wet "tar" build-up. I will NOT use these plugs again, as per Larry's advice. (Actually, it was more like a directive, or an order, rather than advice... lol) I appreciate his kind help and his knowledge. I truly never intended to learn even half as much about ICE engines (I know, redundant redundancy - Internal Combustion Engine Engine - that's like Japanese place names translated to English - "Mount Fuji-san" = Mount Fuji Mountain, or Lake Hamanako = Lake Hamano Lake... rotfl), but as I'm learning more, I am becoming more competent with maintaining my wife's car, and my new-to-me 13 year old Toyota BB (Scion xB in North America).
Summary:
The "collar" is critical! Likely it allows more engine casing heat to permeate the body of the spark plug, keeping it at a high enough temperature to burn off the carbon (above 500C). (Refer to the 3 photos attached - 2x specified plugs, Denso and NGK, and 1x alternate iridium version of the NGK, and note they all have collars. While the Denso is slightly different shape than the NGK, it is clearly present. I'll measure the diameters and heights of the NGK vs Denso collars once they arrive and post for everyone's interest and popcorn eating fodder for thought...)
The "pros" installed plugs that do NOT have this collar, and hence are WRONG WRONG WRONG!!! And the proof is the wet black tar buildup. (Look at my photo in an early post in this thread.)
I think I'm done for now... The floor is open for piling on... But there's no need to repeat that the "pros" did not install wrong plugs. They DID install wrong plugs, and we're well past that point already...
Cheers mates!