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Noob spark plug question

19K views 94 replies 16 participants last post by  brown986  
#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.
 
#2 ·
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.

 
#3 ·
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.

 
#7 ·
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.
 
#27 ·
is this true? I always check them in line. But I never knew they needed compression to spark. Is this all harleys or just the twincam? I have a buddy right now wanting me to look at his bike because of no spark so guess I need to ask him how he checked that. Interesting. Learn something Everytime I get on here lol.
 
#13 · (Edited)
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
 
#14 ·
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.
 
#19 ·
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 !
 
#20 ·
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 !
 
#24 ·
Just for future reference, though I am sure you saw on the site, but both J&P Cycles and Dennis Kirk have a "garage" thing where, if you signed up for an account, you can put one or more motorcycles saved in there and filter any given parts category to only those that list fitment for your ride. DK also has a listing of parts that "possibly will fit but aren't specifically designed for this ride".

Fitment listings will be based on the manufacturer of the parts and might not always be accurate, especially on modified bikes, but they should be accurate 99.9% of the time. Anyway, it's a good way to find a lot of parts that will fit, even if you don't order from them, you can even get the manufacturer part number from the site for cross referencing other brands and websites that might carry different brands that they don't have.

Both sites also have free shipping once you reach a certain pre-tax amount (something like $90+ worth of stuff).

There's other websites too, like Revzilla where you can get aftermarket parts. J&P and DK both mostly carry the same parts at the same price, but sometime one or the other will have a better price on a certain product or might have a few different brands from each other.

If you live on the east coast, shipment from either is usually pretty quick and most times it ships out the same or very next day. Like, they don't dick around getting them out. And USPS seems to be faster on the east coast. It's pretty rare that I have had to wait longer than 3 days from the time of order from either to get my parts (if I ordered early in the day Monday - Saturday), and I always pick the cheapest shipping.
 
#32 ·
We dont buy metric plugs for an SAE bike. The ONLY thing I buy from HD is spark plugs.
HD plugs, no one knows who makes them. They are all made in China I bet.
 
#33 ·
I have been using Champion RA8HC's No problems and I can pick them up at the local AP store.
 
#37 ·
There have been a couple of recommendations regarding good functioning fob. This is new to me as my ride is an 04 & its fob I don't believe is critical for starting. Are these fob recommendations due to the newer fobs that work automatically, i.e. lock & arm automatically as you walk away from the bike a certain distance?
 
#48 ·
I no longer have my 05, but when I did, I had the auto arm feature turned off.

I found it more of an annoyance than a benefit, cause I never armed my bike manually when I parked it for the day in the garage. I was always tripping the alarm when I tried to take off the next day.
 
#49 ·
Thanks Kainam. I've always intended to add the siren but never got around to it. Just looked them up & learned the current sirens come w/a 9 Volt rechargeable Nikel Metal hydride battery; believe back in 04 it did not have a recharge capability or maybe it did. Did you have a siren on your '05 & if so do you recall if its battery was rechargeable? Anyway, I just ordered one & it will give me something to do in the garage during this long & bitterly cold South Dakota winter!
 
#50 ·
Yeah, I added the siren myself. Pretty simple install. The battery automatically recharges off the motorcycle's 12V electrical system. I've never had to replace the 9V battery. When I traded the 05 in on my 21, I migrated the siren to the new bike.
 
#60 ·
I'm waiting on the fuel filter that was lost in the post from Amazon. It was taken out with the tornado in Tenn. Once I have that I will get it all done at one time. I have to drain the tank and take it off to get the plug wires and I will also run the wiring for the satellite radio and what not.I should be able to get started this weekend.