Spark plugs
Grand HDF Member
Joined: Mar 2011
Posts: 4,816
Likes: 1,320
From: Good roads, cold beer
am on a few small engine forums and this has been brought up w/ NGKs. I use them in any small engine I have whenever possible.
Road Master
Joined: Nov 2009
Posts: 771
Likes: 572
From: Northern Lower Mi.
Seasoned HDF Member
Joined: May 2008
Posts: 21,173
Likes: 12,740
From: South Carolina
Earlier service manuals call for anti seize on spark plug threads, but M8 service manual says spark plugs must be clean and dry.
I go by the whatever the service manual calls out.
I go by the whatever the service manual calls out.
Last edited by Dan89FLSTC; Jan 16, 2022 at 01:07 PM.
Road Warrior
Joined: Nov 2018
Posts: 1,277
Likes: 1,018
From: Eastern Ont.
I always put a thin coat on my shovels, evos and TC's. Never had a problem. I havent changed the plugs yet in our M8's. The wife and I had a pair of 107 STG's and traded them at different times for 114 STGS. I figure keep trading and i wont have to worry about, do i or dont i, use anti seize.
Road Warrior
Joined: Aug 2008
Posts: 1,306
Likes: 865
From: Sheboygan, WI
the first post I quoted shows a 10mm thread chaser next to a harley plug, so I'm guessing its from an m8. I'll keep putting antiseize on my M8 also...
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Seasoned HDF Member
Joined: Sep 2008
Posts: 14,156
Likes: 11,247
From: San Diego, CA
Using anti-seize can't hurt...
Unless you use a torque wrench to tighten your plugs, and use a "dry torque spec" for a plug with anti-seize... In that scenario, you will be over-torquing your plug and could damage threads...
