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1999 Ultra classic
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Discussion Starter · #1 ·
First HD, and I'm having small issues. A bit of the old background, I have been riding for about 3 years now but my first "real" bike was and is a Honda Shadow that I fully built myself. Full frame off restoration so I know metric bikes OK.
But Being 6'5 that bike was and is a tad bit to small I look like a Grizzly on a bicycle at the circus. LOL
So a friend of mine who has had a heart attack and is now finishing his cancer treatments ( yes he beat it and is now in remission) who can no longer ride pretty much gave me his '99 Ultra Glide.

I'm doing a good bit of normal maintenance before I ride it. It has been sitting for about 1 1/2 years. Getting ready to replace the CPS because it has now spark to the plugs. It ran last week just fine. I drained the tank changed the gas and rode it home and for a bit the following day. It did have a hard time starting but it started. Now nothing, it will crank all day but no spark. Not a big deal, but the spark plugs themselves look like they have seen better days.
Can I just grab spark plugs from like Auto Zone or do they have to be "special" plugs from HD? The Honda have different sizes from normal plugs so you have to go to Honda to get the plugs.
I want to replace the plug wires as well but I have those. This will get 1 of the items off my "to do" list on this bike.
 

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weird member
1997 Softail Custom (FXSTC)
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They just need to be the right size and be frequency resistor/resistance or whatever it is.

If you look on Google, there's actually a chart somewhere of equivalent plugs from Champion, NGK and others to plugs specified in the owner's manual.

Quick Google search, plug listed for 99 Ultra is RA8HC. Just search for equivalent plugs. NGK and Denso are good spark plugs.

 

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Cross reference chart + link to an android app I wrote so you dont have to write the plug numbers down when you go shopping for plugs.

 

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1999 Ultra classic
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Discussion Starter · #4 ·
Cross reference chart + link to an android app I wrote so you dont have to write the plug numbers down when you go shopping for plugs.

Thanks, but damn I miss my android! My company has a love affair with I pones.
 

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Mr. James
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Thanks, but damn I miss my android! My company has a love affair with I pones.
Many companies do. I suppose it's because iPhones are dummy proof-ish and you don't have many settings you can change. And the world is full of dummies.
 

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I guess I'm going to start some controversy with this post !
The only non Harley plugs that seem to function correctly with the ion sense circuit on the TC ignitions are the NGKs. I've remedied TC ignition problems simply by installing H-D plugs in place of the non Harley plugs that were in the heads. Motorcraft, Autolite and Bosch all seem to be problematic with the TC ion sense circuit.
The Scanalyzer and Digital Tech shop computer detect that difference but the ECM doesn't set a code for the ion sense circuit. BTW the ion sense circuit is the 4th wire on the TC ignition coil.
 

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I guess I'm going to start some controversy with this post !
The only non Harley plugs that seem to function correctly with the ion sense circuit on the TC ignitions are the NGKs. I've remedied TC ignition problems simply by installing H-D plugs in place of the non Harley plugs that were in the heads. Motorcraft, Autolite and Bosch all seem to be problematic with the TC ion sense circuit.
The Scanalyzer and Digital Tech shop computer detect that difference but the ECM doesn't set a code for the ion sense circuit. BTW the ion sense circuit is the 4th wire on the TC ignition coil.
So glad they went to a true knock sensor on the M8s. Not as picky on sparkplugs.
 
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weird member
1997 Softail Custom (FXSTC)
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Denso Iridiums are a little better than NGK.

But really either one is good for 100000 miles.
Another advantage of Iridiums is that they have a much stronger spark in low-voltage situations than traditional plugs. Granted, that's only going to be an issue if your battery is near dead, but it can mean the difference between riding it home or having to get a tow if your charging system fails without you realizing it and you've been out running errands on pure battery power and nearly wiped the battery out.

Ask me how I know. 😛

They also have a tendency to resist fouling better than others.

They're expensive compared to traditional copper plugs on initial purchase, but they pay for themselves in the long run due to their much longer life. Long-term, they probably cost about the same as traditional plugs.
 

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Since you are new to HD's, know that you will not get spark with the plugs out, grounded to cyl. The system must sense compression. Leave the plugs in and put a spare in the lead to check.
 

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I don't risk it. I have that ion sensing system.The dealer sells the harley plugs cheap. I paid 9 bucks for both plugs.
About same price at auto parts store.
 

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First HD, and I'm having small issues. A bit of the old background, I have been riding for about 3 years now but my first "real" bike was and is a Honda Shadow that I fully built myself. Full frame off restoration so I know metric bikes OK.
But Being 6'5 that bike was and is a tad bit to small I look like a Grizzly on a bicycle at the circus. LOL
So a friend of mine who has had a heart attack and is now finishing his cancer treatments ( yes he beat it and is now in remission) who can no longer ride pretty much gave me his '99 Ultra Glide.

I'm doing a good bit of normal maintenance before I ride it. It has been sitting for about 1 1/2 years. Getting ready to replace the CPS because it has now spark to the plugs. It ran last week just fine. I drained the tank changed the gas and rode it home and for a bit the following day. It did have a hard time starting but it started. Now nothing, it will crank all day but no spark. Not a big deal, but the spark plugs themselves look like they have seen better days.
Can I just grab spark plugs from like Auto Zone or do they have to be "special" plugs from HD? The Honda have different sizes from normal plugs so you have to go to Honda to get the plugs.
I want to replace the plug wires as well but I have those. This will get 1 of the items off my "to do" list on this bike.
I used to follow Donny Peterson's regular "Tech Line" articles in American Iron magazine. Donny died recently at age 76. In an article he wrote discussing spark plugs for Harleys, he claimed that Champion manufactured most Harley plugs & simply rebranded the Champion plugs to read Harley-Davidson. Assuming your '99 is a Twin Cam 88 like mine, your Champion plug would be RA8HC. I've been running these plugs for many years in my 2004 Dyna LowRider & they work great. Never had a problem.

You can have them quickly & inexpensively here: Amazon.com: Champion Copper Core Plus RA8HC Spark Plug RA8HC : Patio, Lawn & Garden

Dennis Kirk offers them for much less here: Champion Copper Plus Spark Plug - RA8HC Harley Motorcycle | Dennis Kirk
 

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I used to follow Donny Peterson's regular "Tech Line" articles in American Iron magazine. Donny died recently at age 76. In an article he wrote discussing spark plugs for Harleys, he claimed that Champion manufactured most Harley plugs & simply rebranded the Champion plugs to read Harley-Davidson. Assuming your '99 is a Twin Cam 88 like mine, your Champion plug would be RA8HC. I've been running these plugs for many years in my 2004 Dyna LowRider & they work great. Never had a problem.
It wouldn't be a 'rebrand' it would be manufactured to the Harley Davidson specifications part. Just like the batteries made for the MoCo manufactured by Deka or the brakes manufactured to Harley Davidson specifications by Kelsey Hayes and Brembo. The MoCo doesn't manufacture much of their product line, they get specialty companies to manufacture parts for them to their specifications.
And yes I had heard that Champion was the MoCo's spark plug manufacture also.
 
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Hey RJ64 calling someone a dummy over the phone they choose is a bit dickish don't you think? Kind of like calling them a dummy for not riding the bike you choose.. just sayin
 

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Hey RJ64 calling someone a dummy over the phone they choose is a bit dickish don't you think? Kind of like calling them a dummy for not riding the bike you choose.. just sayin
Where does your post fit in this thread ?
 

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It doesn’t, sorry..
Well then maybe start your own thread IMO. I'm just saying that we all need to stay on context is all. Start a new thread if need be to address your concerns. Your concerns were cellphones, nothing to do with the topic ! Remember the topic was SPARK PLUGS !
 

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This HDF forum, it's so easy to get off topic is crazy ! I've been around here pretty long and the off topic syndrome has plagued this forum for as long as I've been a member ! It ain't never going away either because of the format !
 
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