You'll know if the bike's anti-knock system is malfunctioning due to the aftermarket plugs... it will turn on the check engine light and throw a code in that case.

Having said that... why chance it? Buy the plug that is manufactured to operate in the ohm range the anti-knock system is looking for. That would be the OEM spark plug.

 

I just put champions in my 11 EGC. No check engine light. Had it dyno'd with the new cams. Runs great.

 

Never heard of that. Not anything in my service manual about it. Followed all the links to where this was supposed to be from and there's nothing there. Seems to be one of those "I read it on the internet so it must be true" things...

 

You've never heard of FuelMoto? Look at the second post on that link and you will see that it's not one of those "read it on the internet" things. My PowerVision even has a section to turn anti-knock on and off.

 

I just bought a set of NGK Iridium plugs and damn, they are nice! I've been using the regular NGK for a long time with no issues, but these iridium plugs are something else! Hardly any pings and the engine runs smoother too!

 

It is just FM being careful, nowhere do they say use of non-HD spark plugs will disable the ion-sensing feature. And the sepst and tts has the feature to disable, you tune with the feature off then after you are done tuning you turn it back on. At least that how I was told it should be done. You don't want the ecm to retard if you can help it.

 

I did so more searching and I stand corrected.

http://harleytechtalk.org/htt/index....c,41271.0.html

 

But did you see that the only verified bad plug for the ion sensing was an HD 6r12 plug?

 

I don't think it's a matter of them being careful. There are some plugs that do disable anti-knock. Don't know which off hand. There are so many brands of plugs that they can't research each and every one to be sure they have the resistance needed.

And it's one of those situations where..... plugs are cheap. Why save a buck or two, when you don't have to change them that often. It's like those guys who hunt for O rings from other vendors to save a few cents, rather than just grab a few at the dealer.

If they are so anti-dealer, and anti-Harley, maybe they would be happier with a metric, or a Polaris product.

 

There certainly could be spark plugs that could fall out of the range. There can be stock plugs that could be bad, I saw that in the above post. Also the gap effects the ability of the ecm to read the "knock" . The safe thing to do is recommend stock 6r12 plugs and use the recommended gap, if i was sending out maps to people Id tell them to use stockers(wires and plugs) so that way it takes much of the guesswork out of any trouble shooting incase there are knock problems. You do notice that fm has their own ion safe spark plug wires, so why can't other plugs and wires be ion safe too? Now I have a dyno tuner that checks all that stuff and I have brought my stock plug wires with me incase my non oem wires cause an issue and have talked with him at length about this ion sensing and if there was an issue with any plug I had in the head I would have been told. Not saying it couldn't happen, just that even with champions and or autolites and non stock plug wires I have not seen any disabling of the ion knock sensor ..................yet, LOL