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Unique spark plug problem

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Old Jun 26, 2021 | 06:19 PM
  #11  
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Let us know how many miles that new plug holds for, ok?
 
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Old Jun 26, 2021 | 09:41 PM
  #12  
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Thanks everyone for the help and advice. Good stuff.

I feel pretty confident that there is plenty of threads left in the cylinder head to hold the plug.

Agreed on points and spark plug gap.

Now on to the next problem that will appear sooner than later. I just want to ride the bike this summer.

I keep telling my wife that I’m glad I have the 2014 UL because the shovel pisses me off most of the time.
 
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Old Jun 26, 2021 | 10:21 PM
  #13  
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Don't go all cheap backyard redneck on it at this point. Repair the thread, it can be done head still on, fairly easy to do also, just needs a steady hand and some sense. There's less meat in there than you think at this point. Kits are reasonable. Use bee's or cutting wax on the tap to catch the chips then clean thoroughly with acetone or brake cleaner and blow out any left with compressed air. Anything that might be in there is very fine aluminium and will blow the first 3 seconds she's running High heat retaining Loctite #620 on the insert, install and let sit overnight. I've lost track of how many I've done in frame like this.





 
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Old Jun 27, 2021 | 08:43 AM
  #14  
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What plugs do you like? I’m interested in trying some others.
 
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Old Jun 27, 2021 | 08:51 AM
  #15  
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Originally Posted by Lowoilpressure
Ok, I've learned a bit about plugs and more about my bike. I don't know why the previous owner had those stubby plugs in this bike. As stated, the spark was occurring in the threaded channel before the cylinder head since the plug was the wrong one. Totally bizarre.

I bought a new plug, the correct one with the longer threads. Since half or more of the threads were still good was able to just screw in the new plug. Fits nice. The bike is running sweetly again.

Oddly, the bike ran nice even with those stubby spark plugs.

With the gap, I gapped it a .036. I have an S&S carb and the instructions from S&S say the gap should be .021 but Harley says .038 to .042

Speaking of gaps. On my points, it seems people generally like .014 to .018. My moco manual says .006. I just don't know who to believe.
I have my points at .016

Tom
.006 is for the air space on electronic ignition ... Not for a "points and condensor" set up


 
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Old Jun 27, 2021 | 09:38 AM
  #16  
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Originally Posted by mbco
What plugs do you like? I’m interested in trying some others.
AC, or NGK , my choice was Bosch platinums when I could still find them. Don't have the plug numbers off hand sorry.

What you don't want is the plugs with the extra long electrode hanging down , this can clip a valve or kiss the top of the pistons.
 
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Old Jun 27, 2021 | 09:47 AM
  #17  
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I’m definitely not going to redneck this bike. I’ve spent months a $$$$ undoing the previous owner(s) redneck modifications.
I do feel pretty confident that the threads are going to work for now. It’s almost July and I would like to get at least a few months of Minnesota riding season in. Plenty to do on it this winter.

I am dumping the Champion brand plugs since most everyone seems to poo poo them. I bought NGK this time.
In the following photo shows the old Chamion plug which is WRONG and the new plug I bought. Much longer threads.

Once again, I have this dorky 79 engine but this was the transition year where everything is a mess in the book. I have points which I think they used until mid 1978 or there abouts. Looking more closely at the book, Uncle Larry is right. The timing of .006 is not for points. I have my points at .016 for now. Plugs are .038



 
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Old Jun 27, 2021 | 06:47 PM
  #18  
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Originally Posted by Lowoilpressure
Thanks everyone for the help and advice. Good stuff.

I feel pretty confident that there is plenty of threads left in the cylinder head to hold the plug.

Agreed on points and spark plug gap.

Now on to the next problem that will appear sooner than later. I just want to ride the bike this summer.

I keep telling my wife that I’m glad I have the 2014 UL because the shovel pisses me off most of the time.
whats a UL ?
 
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Old Jun 27, 2021 | 07:15 PM
  #19  
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Originally Posted by john lee
whats a UL ?
Ultra Limited ???
 
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Old Jun 27, 2021 | 07:21 PM
  #20  
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Bit of advice on owning a shovel? They are only as good as their present and past owners. Most shovels suffer from owneritus to some degree, why there so many horror stories about them that will never fade away.

Fix the issues correctly as they come up and you won't be adding to the myth shovels are junk and they'll give you far fewer problems in the long run.

Good luck on that plug.
 
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