Is anyone running the E3 spark plug?
Ultimate HDF Member
Joined: Dec 2008
Posts: 5,120
Likes: 17
From: Indiana
I was running them in all my vehicles, but then I heard they go bad and start to misfire because of the multiple points. Well shortly after I heard that I had 2 go bad in my SUV and one in my car. So I removed them from the SUV, car and bike. I run iridiums now and those have been the best for me. A lot smoother and the bike doesn't sound so rough at start up when the bike is cold like it did with the stockers. I tried going back to stock plugs on the bike, but it just seemed so rough. With stock plugs it would turn over a couple times before it would fire and when started the bike would sputter/cough till the bike was warmed up after a block or two. With the iridiums the bike fires right up and no sputtering. The iridiums have been great! I wouldn't go with the E3's again.
Last edited by JaronB; Feb 24, 2011 at 12:14 AM.
Road Captain
Joined: Jul 2009
Posts: 624
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From: NorthEast Ohio
I won't try because electricity will ONLY go to the nearest ground. So that three pointer is only going to spark across the nearest one point. The only advantage of the three points would be when the closest point burns away, the next closest point will then get the spark jump. But what usually happens is all the points will get a carbon build up on them and you won't get that great a spark anyway.
Road Master
Joined: Sep 2008
Posts: 1,240
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From: Milwaukee area
I gave up on multi-tipped spark plugs years ago, after trying the Splitfires when they first hit the market. Car always ran rough and eventually wouldn't start. Diagnosed it as a bad plug, so I replaced it. Still ran rough and again refused to start. Same problem, different plug. Yanked them all and put in some NGKs. Ran smoother and didn't develop starting issues.
I currently am using E3.36 and have enjoyed them thus far. Granted I only have a couple of hundred on them so only time will tell if I run into the issues mentioned previously, I will keep iridium in the back of my mind.
After installing them I was impressed with the immediate increase in performance, better response as well. The idle was a bit higher and had to be adjusted.
After installing them I was impressed with the immediate increase in performance, better response as well. The idle was a bit higher and had to be adjusted.
Road Warrior
Joined: Apr 2010
Posts: 1,739
Likes: 10
From: Suffolk, England
Same advice I always give to owners of late-models Harleys thinking of swapping out the plugs...
These bikes have an anti-knock system that relies on ion-sensing through the spark plug circuit. Swap to other plugs and the characteristics of this circuit change, which can mean either the the ECU can no longer work out if knock is happening and so can't adjust the timing or else, even worse, it thinks the engine is knocking all the time and adjusts the timing permanently.
There is absolutely nothing wrong with the stock plugs and I defy anyone to show any improvement with another brand unless you are swapping old knackered plugs for new. And, because of ion sensing, you risk making the bike run a lot worse and/or damaging the engine.
These bikes have an anti-knock system that relies on ion-sensing through the spark plug circuit. Swap to other plugs and the characteristics of this circuit change, which can mean either the the ECU can no longer work out if knock is happening and so can't adjust the timing or else, even worse, it thinks the engine is knocking all the time and adjusts the timing permanently.
There is absolutely nothing wrong with the stock plugs and I defy anyone to show any improvement with another brand unless you are swapping old knackered plugs for new. And, because of ion sensing, you risk making the bike run a lot worse and/or damaging the engine.
Ultimate HDF Member
Joined: May 2008
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From: Ogden, UT
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Ultimate HDF Member
Joined: Dec 2008
Posts: 5,120
Likes: 17
From: Indiana
Same advice I always give to owners of late-models Harleys thinking of swapping out the plugs...
These bikes have an anti-knock system that relies on ion-sensing through the spark plug circuit. Swap to other plugs and the characteristics of this circuit change, which can mean either the the ECU can no longer work out if knock is happening and so can't adjust the timing or else, even worse, it thinks the engine is knocking all the time and adjusts the timing permanently.
There is absolutely nothing wrong with the stock plugs and I defy anyone to show any improvement with another brand unless you are swapping old knackered plugs for new. And, because of ion sensing, you risk making the bike run a lot worse and/or damaging the engine.
These bikes have an anti-knock system that relies on ion-sensing through the spark plug circuit. Swap to other plugs and the characteristics of this circuit change, which can mean either the the ECU can no longer work out if knock is happening and so can't adjust the timing or else, even worse, it thinks the engine is knocking all the time and adjusts the timing permanently.
There is absolutely nothing wrong with the stock plugs and I defy anyone to show any improvement with another brand unless you are swapping old knackered plugs for new. And, because of ion sensing, you risk making the bike run a lot worse and/or damaging the engine.
Last edited by JaronB; Feb 24, 2011 at 06:05 PM.
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From what I've read in the past changing from stock to say NGK iridiums you aren't messing with circuit voltage. All you're doing is changing the output of the spark because of the center electrode, but basically the plugs are basically the same internally. Which means nothing should change. I went from stock to E3's, to stock and now iridiums and by far the bike is smoother, no knocking and acceleration especially cold is so much better with iridiums. I'm no pro at this stuff, that's just my experience.
Ultimate HDF Member
Joined: May 2008
Posts: 6,642
Likes: 48
From: Ogden, UT
I will be looking forward to the response, thanks.