Best spark plugs
Outstanding HDF Member
Joined: Feb 2007
Posts: 2,976
Likes: 49
From: Northern California
Pulstars right now are what has been in my bike about 5-6k miles. Starts a little quicker and seems to run a little crisper. Never been on a dyno to compare.
Before you dinosaurs start flaming away remember it is not bash the spark plug question.
If all a bike needed was a spark in the chamber and new design plugs did not make an improvement then why are the big three using modern design plugs.
For me with the few different plugs I have tried in my post 2003 HD motors these Pulstars are the best of the bunch.
Ok I kicked the caveman cage, get ready for the screeching.
Before you dinosaurs start flaming away remember it is not bash the spark plug question.
If all a bike needed was a spark in the chamber and new design plugs did not make an improvement then why are the big three using modern design plugs.
For me with the few different plugs I have tried in my post 2003 HD motors these Pulstars are the best of the bunch.
Ok I kicked the caveman cage, get ready for the screeching.
Elite HDF Member
Joined: Mar 2014
Posts: 4,214
Likes: 661
From: Prior Lake, MN
If by the big three, you mean GM, Ford, and Chrysler- your logic is a bit flawed.
The reason that car makers use the plugs they do is to extend the spark plug change interval. It's a royal PITA to reach the plugs on some cars, especially transverse mounted V6- try reaching the back 3 plugs. No thanks.
My car has a 100K mile plug change schedule. They use expensive iridium (or whatever) plugs to reach that 100K mile lifespan. Not because they "spark" better, but because they last a long long time.
The service for my Limited calls for new plugs every other year- and they're very easy to change. And they're relatively inexpensive.
You like pulsars, or whatever, more power to you, it's your bike and your money.
Ride on.
Ultimate HDF Member
Joined: Jan 2008
Posts: 6,532
Likes: 132
From: SoCal
There are advantages to exposing the spark in a certain way. Index washers aren't made for looks. But the gains are very small in applications where they have exhausted every other path already to gain hp. With the kind of parasitic drag our bikes have it's likely you wouldn't see any gain.
Intermediate
Joined: Jul 2014
Posts: 48
Likes: 1
From: orillia
Yet another spark plug post
Was at my local Harley dealer yesterday and had a chat about plugs. Was picking up some for my 09 Electra. The service manager said they have found through servicing the bikes that there is no difference between Harley stock $5.49 (Canada) stock plugs and other other plugs in Harley bikes in performance or gas mileage, particularly the touring bikes. Revisited the point that it is a matter of maintaining the machine for optimum performance ie; regular filter, plug, oil changes in the 5000 km range. Said not to waste my money of the $24.95 SE plugs or any other expensive plugs.
I do business with this dealership on another basis so did not expect any B.S. stories about how great the more expensive plugs will make my bike run and did not get any. We sometimes convince ourselves that the bike, boat, car, sled etc is running much better because we have attached some expensive part to it when in fact if we dynoed it or actually calculated the mileage differences they will be non-existent or negligable at best.
I do business with this dealership on another basis so did not expect any B.S. stories about how great the more expensive plugs will make my bike run and did not get any. We sometimes convince ourselves that the bike, boat, car, sled etc is running much better because we have attached some expensive part to it when in fact if we dynoed it or actually calculated the mileage differences they will be non-existent or negligable at best.
Ultimate HDF Member
Joined: Jul 2014
Posts: 8,251
Likes: 3,990
From: Windwardside, Saba N.A.
Used to index plugs in the dual-plugged Shovelhead chop but newer chambers have improved swirl.
Road Captain
Joined: Jun 2011
Posts: 594
Likes: 10
From: Seminole County, FL
If you want to get more out of your plugs, give them more power!
I changed to Accel Super Coils last year and can't get over the improvement. I am currently using S.E. Plugs that I got to try to clear up the error codes for knock problem. Turned out I had a bad connection post on the coil.
One of the best mods I have ever done for what it's worth.
I changed to Accel Super Coils last year and can't get over the improvement. I am currently using S.E. Plugs that I got to try to clear up the error codes for knock problem. Turned out I had a bad connection post on the coil.
One of the best mods I have ever done for what it's worth.
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Extreme HDF Member
Joined: Dec 2007
Posts: 13,402
Likes: 941
From: Illinois
There are differences in plug performance. It simply is not that all are identical.
Do research on testing not submitting personal opinions.
The iridium plugs are now used in all Toyota, GM and other makers because of their advantages. If they did not do the job car manufacturers use the lowest cost product that they can and not the higher priced like iridium plugs.
In a lean burn engine the concentrated spark from the tiny iridium wire ignites the mixture faster which in return facilitates more of the charge to be burned during the power stroke.
What does that mean? First from 1 to 3 % more power, less fuel emissions and better miles to gallon. Now it is a very small gain but a gain never the less.
The ever increasing regulation to achieve higher mpg's and lower emmisions has lead the car companies to rely on all the strategies that they can. That is why the more costly iridium plugs are in their cars.
Now if you have a high compression built engine whether in a hot rod or bike with the proper AFR then there is no gain from iridium plugs. The old copper core is still the best in that use.
Now in a low compression lean burn (14.7 to 1) 103 at 70 hp there can be a gain of .7 of a hp up to about 2 hp. And don't you just love that your carbon foot print would be a small iota less? And the icing on the cake is about a mile per gallon more.
But and it is a big BUTT who has the same stock AFR that their bike came with?
And that gentlemen is the rest of the story.
Do research on testing not submitting personal opinions.
The iridium plugs are now used in all Toyota, GM and other makers because of their advantages. If they did not do the job car manufacturers use the lowest cost product that they can and not the higher priced like iridium plugs.
In a lean burn engine the concentrated spark from the tiny iridium wire ignites the mixture faster which in return facilitates more of the charge to be burned during the power stroke.
What does that mean? First from 1 to 3 % more power, less fuel emissions and better miles to gallon. Now it is a very small gain but a gain never the less.
The ever increasing regulation to achieve higher mpg's and lower emmisions has lead the car companies to rely on all the strategies that they can. That is why the more costly iridium plugs are in their cars.
Now if you have a high compression built engine whether in a hot rod or bike with the proper AFR then there is no gain from iridium plugs. The old copper core is still the best in that use.
Now in a low compression lean burn (14.7 to 1) 103 at 70 hp there can be a gain of .7 of a hp up to about 2 hp. And don't you just love that your carbon foot print would be a small iota less? And the icing on the cake is about a mile per gallon more.
But and it is a big BUTT who has the same stock AFR that their bike came with?
And that gentlemen is the rest of the story.