Best spark plugs
Elite HDF Member
Joined: Nov 2006
Posts: 3,909
Likes: 6
From: Livingston, Texas
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..
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..
Elite HDF Member
Joined: Nov 2006
Posts: 3,909
Likes: 6
From: Livingston, Texas
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
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
Road Master
Joined: Jan 2008
Posts: 959
Likes: 5
From: Oswego, IL
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.
Point being watch your plug size of you use bridges.
Elite HDF Member
Joined: Nov 2006
Posts: 3,909
Likes: 6
From: Livingston, Texas
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.
Point being watch your plug size of you use bridges.
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
Road Master
Joined: Jan 2008
Posts: 959
Likes: 5
From: Oswego, IL
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Road Captain
Joined: Jun 2013
Posts: 669
Likes: 4
From: Rockwall,TX
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