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CB500/550 / Re: Plugs fouling at idle
« Last post by deltarider on Today at 02:14:47 PM »Compare the above to what they gave me as answer, after I took the effort to contact them.The fact that the L was a half grade came from the same reptat suggested d7ev to me, and that man knew how to read plugs
Thats noted on some published charts too .... the -L designation.
https://www.ngk.com/ngk-spark-plug-numbering-systems this lists that design element, although note that they have a statement of NOT being NGK USA official scource.
The listed data looks comprehensive though.
My question was:
Dear Cust,
Here's a question owners of motorcycles that had the NGK D8ES-L sparkplug prescribed, never had answered:
Is the D8EA plug, as far as heat range, the same as its predecessor D8ES-L?
In addition:
Is the D7EA plug just a renamed D7ES, or does the -A suffix ('Special Design') imply the D7ES was indeed modified?
Core of our uncertainty is, that we have no clue what the meaning of 'Special Design' is.
We realise it may be difficult for you to find the answer. You may have to consult older employees who can remember. Somebody must know.
The issue has been debated over and over in various fora around the world (Germany, Holland, France, UK and US) and no NGK chart ever solved the uncertainty. https://www.ngk.com/ngk-spark-plug-numbering-systems
And here the answer:
Hello,
Thank you for contacting us! D8EA had a heat range of 8 and D8ES-L heat range 8.5. The (L) stands for Half Heat Range.
As a Distributor for NGK the -A suffix ('Special Design') is still a mystery to us. You will have to contact NGK directly at 1-877-473-6767 ext #1 or www.ngksparkplugs.com they may have more details on this.
Personally I find it hard to believe that the D8ES-L has heat range 8.5.
Your comments please.