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Spark Plug ?

formike56

Junior Member
I was having a stutter or popping while accelerating. Didn't happen all the time. I have 8,000 miles on the rebuild. Went to dealer pickup new Spark plugs. Bought the stock gold HD plugs. When I puller th front plug it was perfect color. Light tan, no excessive wear. Gap was good. Pulled rear plug.. It was a darker grey. Gap was good. Little carbon color to it. Neither had any moisture on them. Ran bike this morning no more popping. Question is would plug be bad after that many miles? If it wasn't firing correctly. Wouldn't it be fouled? Would it be better to have a hotter plug. Where the jug with the carbon was?
 
The rear plug will always be darker than the front plug. I have seen many plugs that were bad internally and caused a problem with a misfire. I wouldn't change the plug for the rear cylinder only myself.
 
The rear plug will always be darker than the front plug. I have seen many plugs that were bad internally and caused a problem with a misfire. I wouldn't change the plug for the rear cylinder only myself.

Thanks Glider. My thoughts also. Just had to ask.
 
I also use the HG Gold on my 06 FXDCI. I just changed them at 20,000 miles. Put them in at 5,000. I didn't see any excessive wear, just the electrode and the ceramic was shorter. I check them twice a year for wear, clean and re-gap.
 
Having been riding bikes for many years i have in the past seen plugs fail with no apparent damage
so i tend to change them regularly and keep the old ones in the tool bag just in case one goes faulty when I'm on the road

Brian
 
I am with Brian on this, change out HD Gold plugs about once a year with new, clean and gap the old ones as backup and rotate out. Hey, that tool bag/roll is my road kit, cloth work apron with compartments for hex/torx plug wrench, gooseneck crecent, screwdriver 6 in 1, bailing wire, zip ties, tire plug kit/inflator, mini jumper cables, spare fuses and I am good to go.
 
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I am with Brian on this, change out HD Gold plugs about once a year with new, clean and gap the old ones as backup and rotate out. Hey, that tool bag/roll is my road kit, cloth work apron with compartments for hex/torx plug wrench, gooseneck crecent, screwdriver 6 in 1, bailing wire, zip ties, tire plug kit/inflator, mini jumper cables, spare fuses and I am good to go.

I used to keep a set of spares when I had the "77" Iron Head Sporty. It was bad for fouling plugs. Was running a S&S Super E. It loved to dump fuel in it. When it ran good.... It ran like a scalded dog....
 
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