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Old Sep 24, 2016 | 08:04 PM
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I pulled the plugs out of my '09 Ultra. One of them has like a brown waxy material on the insulator and was all in the boot as well. Haven't see this before, it was not on the other plug. It's an NGK plug. Anyone know what this would be from? Plug leaking?

Also, any of you with the FM 107 build, do you put the OEM plugs in your bike, or do you put a better plug in?


 

Last edited by jamala00; Sep 24, 2016 at 08:07 PM.
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Old Sep 24, 2016 | 08:21 PM
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Looks like some type of spark plug boot grease. Dielectric Grease can be found at any auto parts store.
 
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Old Sep 24, 2016 | 08:23 PM
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Ya, I've used Dielectric grease before. Not on plugs, but I've used it. Just weird it was only on one. It wasn't me who changed the plugs last, I suppose the shop could have used it. But I just think it would have been on both.
 
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Old Sep 25, 2016 | 12:13 AM
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Yes I agree. Why do just one?
 
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Old Sep 25, 2016 | 01:19 AM
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I have an FM 107. Stock plugs are fine. The only thing that "better" plugs are better at is wasting your money.
 

Last edited by Keithhu; Sep 25, 2016 at 03:51 AM.
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Old Sep 25, 2016 | 02:05 AM
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Stock plugs are fine, just check if it need re gap
 
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Old Sep 25, 2016 | 06:31 AM
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Originally Posted by 103 sedona orange
Yes I agree. Why do just one?
Originally Posted by Keithhu
I have an FM 107. Stock plugs are fine. The only thing that "better" plugs are better at is wasting your money.
right, right... I'm changing both. :-) I just noticed this on one plug when I had them out. I've always just used the NGK also. Thanks Guys...
 
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Old Sep 25, 2016 | 07:48 AM
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Agree that the stock plugs are just fine. The so-called "better" plugs just create more heat and that's something you don't want. Was this the fist plug change since 2009?
 
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Old Sep 25, 2016 | 07:50 AM
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Originally Posted by Lowcountry Joe
Agree that the stock plugs are just fine. The so-called "better" plugs just create more heat and that's something you don't want. Was this the fist plug change since 2009?
No, this will be the 3rd. I've got just over 50K now. I think I have 20K ish on these plugs
 
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Old Sep 25, 2016 | 07:55 AM
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Looks like someone used general purpose grease in the boot and it dried out with the hear. I have seen that before. Dielectric grease should not do that and make the boot easier to get on.
 
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