Best Spark Plugs
Grand HDF Member
Joined: Aug 2008
Posts: 3,601
Likes: 9,915
From: Florida's gorgeous East coast
Yea, it is kinda like asking about oil....but since you asked...here goes:
First I need to let ya know that being down here in Florida, I ride my Evo to work most days. It's the SAME 100 mi (roundtrip) commute over the SAME roads at the SAME time everyday. Been doing it for 8 yrs. As a result, I have gotten to where I can pretty accurately predict how much gas she will take everytime I fill her up, and it will very much depend on how I rode her. It's sort of a game I play with myself and I can generally hit it to within a hundreth of a gallon or so. I know...I know...that's being waaayyyy too "****", but hey, I'm a scientist and I like to "know things".
Now that we have all that outta the way, we'll get to the answer:
NGK Iridium plugs are the only ones I've found to show a measurable improvement in mpg on my daily commute. It's a small difference to be sure, but I calculated the improvement (at today's ridiculous gas prices) paid for the difference in the cost of the plugs in the first 5,000 mi. I change'em out at 10,000 or so.
I don't Dyno my bike, so I have no idea what, if any effect they are having on horsepower or torque.
First I need to let ya know that being down here in Florida, I ride my Evo to work most days. It's the SAME 100 mi (roundtrip) commute over the SAME roads at the SAME time everyday. Been doing it for 8 yrs. As a result, I have gotten to where I can pretty accurately predict how much gas she will take everytime I fill her up, and it will very much depend on how I rode her. It's sort of a game I play with myself and I can generally hit it to within a hundreth of a gallon or so. I know...I know...that's being waaayyyy too "****", but hey, I'm a scientist and I like to "know things".
Now that we have all that outta the way, we'll get to the answer:
NGK Iridium plugs are the only ones I've found to show a measurable improvement in mpg on my daily commute. It's a small difference to be sure, but I calculated the improvement (at today's ridiculous gas prices) paid for the difference in the cost of the plugs in the first 5,000 mi. I change'em out at 10,000 or so.
I don't Dyno my bike, so I have no idea what, if any effect they are having on horsepower or torque.
Tourer
Joined: Feb 2006
Posts: 390
Likes: 1
From: Ozark, AL
Pulstars
I put them in my bike around 5k miles.
Never noticed a difference in anything.
around 10k I developed a miss. After chnging the fuel filter, I noticed the front plug
had carbon at the botom of the insulator. The whole thing would spin in the metal
body.
I took it back and had it replaced. when replacing the rear it felt like it was stripping the threads (I ALWAYS use Antii-siezeand a torque wrench with plug socket). I pulled it out and looked at all the threads....no problems found.
When re installing the plug the threads broke off in the head(*^&^)!
The thread broke off at the point where the gasket is attached.
I took both back and got NGKs.
Never noticed a difference in anything.
around 10k I developed a miss. After chnging the fuel filter, I noticed the front plug
had carbon at the botom of the insulator. The whole thing would spin in the metal
body.
I took it back and had it replaced. when replacing the rear it felt like it was stripping the threads (I ALWAYS use Antii-siezeand a torque wrench with plug socket). I pulled it out and looked at all the threads....no problems found.
When re installing the plug the threads broke off in the head(*^&^)!
The thread broke off at the point where the gasket is attached.
I took both back and got NGKs.
Moderator
Joined: Oct 2012
Posts: 107,687
Likes: 20,116
From: Ft. Worth, TX
I run NGK Iridium in just about everything. It has always been a great performing plug in my cars, trucks and every motorcycle I've ever had. They cost a little more but I've never had one foul or fail to deliver.
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