NGK Plugs
Seasoned HDF Member
Joined: Jan 2008
Posts: 13,674
Likes: 11,463
From: State of Confusion
OM states every 2 years or 30,000 miles whichever comes first..been that way since the TC inception I believe..I used to change them about every 10K for the hell of it since there were only 2 and it was easy to get at, 5 minute job for the cost of a Starbucks Double Espresso Mocha Al Pacino...every 20K with my M8 is my new plan
OM states every 2 years or 30,000 miles whichever comes first..been that way since the TC inception I believe..I used to change them about every 10K for the hell of it since there were only 2 and it was easy to get at, 5 minute job for the cost of a Starbucks Double Espresso Mocha Al Pacino...every 20K with my M8 is my new plan
Extreme HDF Member
Joined: Dec 2007
Posts: 13,402
Likes: 941
From: Illinois
Iridiums do have some advantages. They ignite ethanol fuels better which helps mpg, are self cleaning which makes them last 100K miles. More power-no.
I use them in my bikes as there in no pure gas is this area of the corn belt.
However Toyota, GM and others have went to the more expensive iridiums to help them achieve EPA mpg standards. Car makers don't spend an extra penny on parts unless it works to their advantage.
I use them in my bikes as there in no pure gas is this area of the corn belt.
However Toyota, GM and others have went to the more expensive iridiums to help them achieve EPA mpg standards. Car makers don't spend an extra penny on parts unless it works to their advantage.
Last edited by lh4x4; Apr 20, 2018 at 11:43 PM.
Seasoned HDF Member
Joined: Sep 2009
Posts: 17,148
Likes: 6,171
From: SE Michigan
OM states every 2 years or 30,000 miles whichever comes first..been that way since the TC inception I believe..I used to change them about every 10K for the hell of it since there were only 2 and it was easy to get at, 5 minute job for the cost of a Starbucks Double Espresso Mocha Al Pacino...every 20K with my M8 is my new plan
Seriously, I'm at about 12K miles/year, and my new strategy is to trade every 2 years, never be out of warranty. w0oT.
Intermediate
Joined: Jan 2014
Posts: 38
Likes: 14
From: The wrong side of SD
2017 Ultra Limited with 13,000 miles and OEM plugs wasn't running right. Poor acceleration. Changed the plugs to NGK's and it ran noticeably better. Of the 4 plugs removed, one showed no wear ( looked good ), 2 showed some erosion of the center electrode, 1 had excessive erosion of the center electrode.
Didn't keep the old plugs or I would post pic's.
IMO OEM plugs are junk.
I've heard nothing but good comments on the E3 spark plugs but have never tried them.
Didn't keep the old plugs or I would post pic's.
IMO OEM plugs are junk.
I've heard nothing but good comments on the E3 spark plugs but have never tried them.
Seasoned HDF Member
Joined: Jan 2008
Posts: 13,674
Likes: 11,463
From: State of Confusion
2017 Ultra Limited with 13,000 miles and OEM plugs wasn't running right. Poor acceleration. Changed the plugs to NGK's and it ran noticeably better. Of the 4 plugs removed, one showed no wear ( looked good ), 2 showed some erosion of the center electrode, 1 had excessive erosion of the center electrode.
Didn't keep the old plugs or I would post pic's.
IMO OEM plugs are junk.
I've heard nothing but good comments on the E3 spark plugs but have never tried them.
Didn't keep the old plugs or I would post pic's.
IMO OEM plugs are junk.
I've heard nothing but good comments on the E3 spark plugs but have never tried them.
is your engine stock, SE or aftermarket tuned?
"IMO OEM plugs are junk"
that's an extremely rare statement and isolated opinion so thinking something else is at play here to cause your results
Intermediate
Joined: Jan 2014
Posts: 38
Likes: 14
From: The wrong side of SD
I thought at about 11,000 miles it wasn't pulling away from stops as well as it used to.
Completely stock bike.
The indy mechanic I used to change the plugs test rode the bike before and after. He didn't say anything to me about how it ran before and after until I reported back my impression. He also thought it ran much better.
If the OEM plugs are the best on the market, then why did they start failing so soon. Maybe the NGK's will crap out at 11K also.
I'm not here to tell anybody what to do, only relay my experience.
Completely stock bike.
The indy mechanic I used to change the plugs test rode the bike before and after. He didn't say anything to me about how it ran before and after until I reported back my impression. He also thought it ran much better.
If the OEM plugs are the best on the market, then why did they start failing so soon. Maybe the NGK's will crap out at 11K also.
I'm not here to tell anybody what to do, only relay my experience.
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Seasoned HDF Member
Joined: Jan 2008
Posts: 13,674
Likes: 11,463
From: State of Confusion
I understand..it's just been widely acknowledged and accepted over many many years that OEM are consistent and reliable performers...this and other forums discuss problems ad nauseam but spark plugs just hasn't been of them..and we all know if they were an issue it would be beaten to death
Seasoned HDF Member
Joined: Mar 2009
Posts: 24,732
Likes: 9,241
From: Snow Hill, NC
On my previous motor I had SE double platinum in for about 50000 miles and they were still fine, like I have said previously, it was absolutely not for performance, it was longevity...I just put a set in my transplanted 103HO with about 13000 miles.
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