2nd the automate 4164 Spark Plugs. Orielly carries them too.

 

stock plugs. I don't see a need for anything else.
kroozeabout.

 

Somebody did a dyno on Plugs, And If I remember right Plain Autolite 4164 Plugs came out on top.


Talked with a MMI graduate of years ago that has a Indy shop he has had for years.
He also said Autolite in Harleys.

The dealer sells Champion plugs if I remember right..

 

Don't want to get a thread going like a Oil thread.
But there is a Bike builder that even quoted he only uses Autolite in his street bike and race bikes. And he builds some very fast bikes.

But run in your bike whatever you like. You will gain nothing with iridium or stock plugs.


http://harleytechtalk.org/htt/index.php?topic=47570.0

 

I use Autolite Iridium plugs for longer life. They have the same resistance as stock plugs so the knock system is functional.

Why? Because I can.

 

Ran across a problem getting a neighbors plugs out. He had head bolt bridges and the plug socket would not take them out. Hd plugs are 5/8" and these auto lite plugs were 11/16". Don't know if he had the wrong auto lite plugs or just thats what size they were.

Point being watch your plug size of you use bridges.

 

Yep!
Autolite plug is a different size.
put antiseize on the threads and put them in. When you tighten them you should hold the socket if you pull it to the side.
I never had a problem tighten them or taking them out.

But if you need a 11/16 Spark Plug Socket

http://www.ebay.com/itm/New-Snap-on-...-/271111533226

 

11/16" socket will not fit through the head bolt bridges is what I should have put

 

i use NGK in all the bike i ever owned and never had a problem harley plugs are made by champion nothing special about them

 

well this thread got me to thinkin about the plugs in my bike and I am trying to search for the champion part # for our bikes do you guys know what it is? The best I got so far is to cross the autolite # you all mentioned and it came up with Champion 810 RA8HC Spark Plug