What Spark Plug Do You Use?
Road Warrior
Joined: Feb 2009
Posts: 1,727
Likes: 11
From: TN
If you compare the Champion RA8HC with the Harley OEM 6R12 you will find that with the exception of the price, they are identical. If the writing on the white porcelain of the plug is worth another $3.50/plug, go for it.
Bwana
Autolite 4164s are also great plugs.
Bwana
Autolite 4164s are also great plugs.
Elite HDF Member
Joined: Jun 2006
Posts: 3,572
Likes: 5
From: Templeton California
I know from experience the plugs that come in the bike can go 6 years with no issues other than rust.When I finally got tired of looking at those I replaced them with Iridium just because.
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Seasoned HDF Member
Joined: Apr 2006
Posts: 10,675
Likes: 95
From: Billings,Mt.
I just installed some Champion RA8HC's which are suppose to be crossed with HD 6R12's.
I found the gap on the Champ's to be almost half of what the HD gap is out of the box.I did try to gap them to .035-.040 but the tip is at an angle.I will not use these anymore.
I found the gap on the Champ's to be almost half of what the HD gap is out of the box.I did try to gap them to .035-.040 but the tip is at an angle.I will not use these anymore.