I just changed plugs and wires yesterday. I went with stock plugs and Symax 8mm red wires. My 96 ci 07 FXSTC has a Stage 1 mod. I gapped the plugs to 38 as Doc recommended. Test ride was AWESOME. She definitely runs better and responded quicker. The plugs I pulled were about 43 so at the max gap. Thanks Doc for YOUR infinite wisdom!
Doc, I know that I am a bit late to everything. I have a 03 fat boy. So I am new . I love it as everyone else does. I want to thank you for your videos. You are giving me a ton of information. No way can I ever thank you enough Sir!!!
It amazes me how many people don't know how to do simple maintenance. Thanks for helping the world be a little bit more aware of proper care of their scooters
Going to get spark plugs from the dealership right now thank you for sound advice and taking the time out to do these videos they greatly help us who aren't professional mechanics but can at least do minor repairs and upgrades
Russell Linthicum this is true. I just bought a 2005 Sportster, with 11,000 miles on the clock, on the original front tyre. I’ve just replaced the tyre and the plugs too. Not too sure whether 15 years is a very good service interval though. 🙂
Got 15k on my 2020 and haven’t had a single issue starting it, however it’s been in storage for 6 months (I’m deployed) so I went ahead and bought a new battery, spark plugs and wires. Thank you for the explanation, I almost forgot about swapping them.
Good info .Spark plugs can be cleaned and gap can adjusted. Riding for over 25 years. Plugs have never been a problem. I only had one ever fail completely. A little maintenance goes a long way . .
My Ultra Limited was getting hard to start at 14,000+ miles. Initially thought it was the battery as it is the original battery on a 2016. Decided to put in new plugs and what a difference. Bike fires right up and the power on the road is back. I didn’t realize the amount of power loss the old plugs were causing. I’m going to go with Doc’s advice and replace the every 10,000 miles from here on out.
NGK spark plugs feature what is known as ‘trivalent plating’. This is a silver-or-chrome coloured finish on the threads that is designed to provide corrosion resistance against moisture, chemicals and weathering. The coating also acts as a release agent during spark plug removal. NGK spark plugs are installed at the factory dry, without the use of anti-seize. NGK tech support has received a number of tech calls from installers who have over-tightened spark plugs because of the use of anti-seize. Anti-seize compound can act as a lubricant altering torque values up to 20 percent, increasing the risk of spark plug thread breakage
It's not a bad idea to have some antiseize compound on the thread of the sparkplug, but you have to compensate for the torque-value. This is a good advice you gave. Thank you for sharing your experience and background story. 👍👍👍👍👍. Greetings from The Netherlands
Hey VN, when u take something (voltage) it's the same as receiving, Da. don't try to knock what this guy has to say. He takes the time, has the knowledge and his presentation is relaxed and positive. Thanks Doc.
Good video. I notice many Harley riders spare little expense on their "babies". Most NEVER wait until the mileage specified in the maintenance chart, yet every other machine they own they won't replace a part until it breaks. The arguments that "plugs are cheap", "cheap insurance", "why not just replace them?" makes little sense. If a spark plug cannot last more than 2,000 miles, you bought a crap plug! In the video he refers to the fact that Harley has extended the mileage interval for spark plug replacement and that is for a good reason. "Doc Harley" states the plug is exactly the same. I cannot say with certainty that he is incorrect, but as an auto technician I know plugs have evolved immensely over the last few years. He is absolutely correct when he said the electrodes erode and the gap widens, but the metal which was used was steel or copper. THOSE plugs lasted 30,000 miles in a car. Today the mentality of plug design is to treat the 2 electrodes with platinum or iridium. These 2 precious metals are able to sustain much more abuse without wearing down. Sure, a 2 cylinder engine will fire the plug more often than my Dodge pick up V8, but come on, 2,000 miles!!!? I have much better things to do and remember than to change the Iridium plugs in my Dyna every 2,000 miles. If you're bored and want to "FIX" something on your scooter, check the tire pressure against factory recommended psi. I bet they need air.
Going on a trip with my 2015 road king. While checking everything the stock 6r12 plugs have about 10,000 on looked good but I had another set of fancy iridium plugs in the toolbox. Tossed them in and bike started better & idled better. Wasn’t even gonna change them but glad I did
Doc I could not have said it any more clearly. Perfect, plus check your wires for being dried out and the boots over the plug. I alsways change them out at 10K but i use NGK and changed out to Harley Fat Wires. Tech tip...carry a spare set in your bags...what $15.00 to save headaches. No brainer
I normally change my spark plugs every 1500 miles or 2000 depending if I'm getting ready to head for bike week. I bought this little case that holds two spark plugs. I have three of them and when I change my plugs I put the old ones in this plastic case. That way if someone else riding with us has an issue I have spark plugs with us so we can get back to riding. The only stuff that I use on my bike is Harley-Davidson parts. I'm not going to name aftermarket brands that I try at the beginning when I purchased my first Harley. The parts that these aftermarket people sell just do not have the same quality that a Harley-Davidson part has. I use their spark plugs I use the oil when I change lights it's always Harley-Davidson. Great video a lot of people just do not think about their spark plugs. Even with the frequency of me changing my plugs I can feel a big difference the next time I ride my bike.
Check plug tops, make sure they are tight. Anti seize threads, and a little dielectric grease on plug top and a little in the boot for ease of slip on. Champion Spark Plug Chart shows you how "Spark plugs tell a story", you can find them online, or buy one and stick up in the garage.
Great advise... this video gives you great details on the basic spark plug install . .little steps in this video add up to the proper install . . . no more ' hick' ups'.... thank you
My own experience on my 2007 Ultra I installed true duel exhaust, Vance and Hines mufflers, high intake air and with this a Fuel pack. I have found that between 6 to 10 thousand miles my check engine ligh comes on and takes longer to go off. When I change spark plugs this remedies the problem. Change Spark Plugs Spark!!!
I know it’s a 2 year old video but just wanted to add according to the service interval per manufacture specifications on my 15 Road Glide 103HO it’s replace spark plugs every 2 years/30,000 miles which ever comes first. Yes I strongly agree with you keep it simple what you take out is what you put back in .... unless your doing major engine modifications such as altering the compression, etc than it starts to matter.
Doc Harley, One thing you did not discuss was resistor spark plugs. They have a built-in gap also in the ceramic stem. You can’t see that but that gap also wears down and gets round. I usually change mine every oil change. They’re not that expensive and I ain’t doing anything while I’m waiting for the oil to drain.
My bike has 9k miles on it. Just added a S&S cam and a Vance and Hines exhaust. Been having a very hard time getting it tuned. Pulled the plugs and the gaps were closed (under .020) not sure how that happened but she runs much better with the proper gap
Hi Doc I agree with you, especially for people changing their own. Better performance for less than the price of a value meal, why not? My only thing is my bike has NGK plugs and after talks to NGK they told me no anti-seize because their plugs already have a coating. So I would say check to see if your plugs have a coating before adding anti-seize, could cause you problems over torquing the plugs
Hey Doc Would you mind doing a video explaining the improvements made in the 2024 M8 engine, if any, regarding crankcase breathing and oil getting to the pistons, you’re knowledge, and advice is greatly appreciated
Thank you for sparkplug tips. My 103 has a stage one kit currently which has been tuned at Harley Davidson so I recently changed my sparkplugs on my 2015 Ultra Limited to Screaming Eagle sparkplugs and also upgraded my plug wires to the Screaming Eagle plug wires. Hoping for a little more performance until I go to the next stage 2 kit.
One additional comment to spark plug changing is to not over-tighten. It's easy to do. Best is to check the service manual and use a torque wrench. CAUTION: if you use anti-seize as Doc recommended, the torque value in the service manual DOES NOT APPLY. The torque values in the manual are for clean, dry threads with only the oil from manufacture. Anti-seize will cause much higher thread loads by the time the torque value on the wrench is met.
And ..with the extreme heat the anti seize can get down into your cylinder heads not a good thing.. I base this on car racing if you want your plugs to foul extreme temperatures put some anti seize on them
You're taking about New Plugs and the Gaps. Took the plugs(Factory) out of my 2018 1200 Custom. Checked the gap. One cylinder was at .035. The other at .040. Only 200 miles on Odometer. Replaced them with a set of NGK Iridium. Found over the years the Iridium last longer. Ran a set of NGK in a Street 750. 10k Miles and no wear. NGK said not use Anti Seize. It affects the Ground. And the oil runs down the heat sink.
Great tip Doc. plus spark plugs (not talking about the ones that are hyped to boost your HP rating by 50%, or they are so intense they would ignite space shuttle fuel) are so inexpensive, would only make sense to put in new plugs even at 6 to 8 thousand miles. Your Harley's worth it!!!
Good information. I change my plugs every 10K miles whether they need it or not. I think my service manual for my 2016 HD Streetglide Special says every 35K miles which makes no since.
Great tip, with common sense. The good old school tune up: Plugs, Oil and Filters. I suppose we have done away with points by now but, My old 1980 FXRS80 had points.
They are $4-$10 bucks each depending on brand and where you buy them. Personally I buy the HD silver and change mine with every oil change. But I also ride my bike almost every day, year round. Take care of your ride and it will last longer.
When I was in auto shop on high school (1000 years ago) I was assigned to rebuild an old Maytag GAS POWERED washing machine engine. The spark plug was dated 1918 and it was a fat little guy. Here's the big thing; it had a little 8-bladed fan on the bottom, NOT the typical spark-gap thing (I'm sure there's a name for it but I don't know what it is) like today. Have you ever seen a spark plug like that? BTW, I had to use it and it still worked like it was brand new!
And do not go to hotter range spark plug tips if your riding style is mostly average speed with the usual blasts for kicks. Like the man said, the lower end of the OEM gap is better.
Here's why I disagree with a 10,000 mile spark plug replacement. 1. Engines run closer to the stoichiometric A/F ratio, so plugs stay cleaner. 2. Modern engines have higher ignition voltage, making for a hotter spark and easier to jump the gap. 3. We no longer use lead in the fuel, and fuels are better than those of years past. 4. Engines are better built and have lower blow-by minimizing oil burn and resultant plug contamination. I change mine at 50,000 miles...never a hiccup.
I over looked changing my OEM spark plugs at just under 69K miles. I didn’t notice any performance issues on my then 110” 2015 CVO motor. I plan to change them at 20K miles from now on.
Heres my advice to harley owners. Have a pouch or use your saddle bags and keep four new spark plugs and a ratchet and socket in any harley you use. When you start them cold and one cylinder doesnt fire until it runs for 10 seconds (which is common), change the plugs. Some will miss out and you have to keep reving them when theyre cold, change the plugs. For the record I have had the best luck with auto lite spark plugs. You have to cross reference them to know what size, as my twin cam uses a different size than my evos. Always also be sure to compare the reach of a plug with the old plug, because if your reach is longer you can knock a hole in a piston top or if too short can result in carbon. Also, keep a round plug gap tool on your key ring, so you can gap them
@@LowCountryHarleyDavidson Havent learned that much about the M8 yet though. But from what Ive seen I think the M8 version appears better mechanically than the TC B version due to gear to counter balancers instead of the guide and chain
Iridium plugs have an anode and electrode so hard, they don't wear nearly as fast. Their gap stays constant. Also, torque down your plugs properly. My 1200 Sporty starts right up, cold or hot.
Priceless information, as is your custom Sir. However, I was put off by the increased change interval HD recommendation…it should be shorter than 10K. If a 10K plugs is in such a condition that a simple visual inspection confirms, “definitely needs replacing” then it stands to reason, that a shorter interval is warranted. “PMS” in the U.S. Navy means, Preventive Maintenance System, the thought 💭 process is to KEEP equipment AT peak level performance while heading off failure. Doc, in my humble opinion PMS applied to HD spark plugs would suggest a 5K inspection and/or change. 2020 Fat Boy
Trikes are the way to go ! I swore I would never ride anything EXCEPT an Electra Glide. I just bought a 2019 Freewheeler and I've never looked back. Motorcycling is fun again and I feel much safer. Especially with my lady on the back !
I'm watching this thinking about my car engine, way newer tech and way more power per cc than my HD. Changes the plugs every 10 yrs, car runs fine on cheap ethanol gas, get awesome mileage. I just put some iridium plugs in my bike though:) After 7.000 miles and the original ones looked fine.
@@LowCountryHarleyDavidson I apologize for making an observation and expressing my doubts as to whether or not a spark plug is worn out in such a short service life.
My comment isn't about this video. Supposedly about 5 years ago Harley did a recall on their saddle bags because they just fell off! Fast forward to today I'm reading forums with people who are losing their bags. I think this is a bit of a liability to harley. I think people who lost a bag should form a group to pressure HD to replace the pins with a different mechanism and compensate people the money they spend replacing them. What is your opinion about this. If it was fixed and they are still falling off, it's not fixed. What if one flew off and killed someone? Who would be liable? Something for them to think about.
The reason they increased plug change intervals is the same reason they increased fluid change intervals. It reduces cost of ownership. I still recommend plugs @ 10k, engine oil @ 2500 and primary and trans fluid & 5k. Lubricant quality has improved over time so people argue “ it doesn’t break down as quickly” but changing oil is about removing contaminants more so than oil breakdown. Contaminants come from internal component wear and corrosive chemicals introduced from the combustion chamber.
How about Not using spark plugs at all? TCB (Traction Controlled Braking) out of Texas making head gaskets with 4 spark igniter giving no loss of spark from plug (no plug puts a bolt in spark plug hole just to close it off) an better circular cylinder firing with 4 equally spaced computer controlled sparks, Very Cool! P.S. his braking system for motorcycle great too!
Pick up new plugs today at dealer and they had to stock wires because they carry them in so he then try selling me screaming eagles at $30 I said I'll wait for the stock he thought I was weird but I didn't care I'm starting not like that dealer
Awesome video Doc. I have a question. I have a 2022 Harley Davidson XL883N Iron 883 and was wondering what brand or name of spark plug should I be using in my Iron 883 and what should be the gap?
Just to add I use either dbl platinum or iridium plugs because they last a longer in whines in good cond using little or no oil between oil changes. If your motors tired no plugs will last as long because of oil burning build up if carbon etc on the plugs causing you yo have to change them earlier.
Doc, I pu a 2003dyns wide glide with 50+kmiles. I am changing the plugs. But, should I also change the plug wires ? If so, what kind would you recommend? Thanks for your experienced help.you help us hd bike riders so much.
my honda has just gone over 80000km no problem with the first set. i still don't see a reason to change it if it starts and runs perfectly. maybe at 100000 ill change them
I got 23,500 miles on my RG Never Changed yet 😳 My Dealers never told me to change They Perform all Services on my Bike since day One , Never Changed Very Sad
With your knowledge I am guessing you used to race? A company chooses an average heat range that works in most applications. Once you change the dynamics of your motor then choice is important….Doc
Thanks for this video. My Buick dealer recommended changing the spark plugs on a 2011 Buick LaCrosse, 6cyl, with 87k, and wasn't sure I needed to do that, so I postponed it. I know, I know, this is a HD video, but what you say related to what I'm experiencing. Thanks again!
Nancy, NEVER take a service person's suggestion without doing your own research. I was an auto dealer technician for over 30 years and I have seen SO many dishonest people sell "stuff" to uninformed customers it made me sick. I know a slimy service manager in a dealership who actually told customers every spring they need to drain their anti freeze and install coolant. Then in the fall he would tell the same customers they need to get that coolant out of the engine and install anti freeze!!! Anti freeze is simply another name for coolant. They are the same thing and for the last 20 years or so, new cars come with coolant which is good for 5 years!! When you bought that car it came with an Owners Manual in the glove box, you know, that little book which is STILL wrapped in the cellophane. lol Near the back of that manual you will see a "Maintenance Chart". That chart will list EVERY part which needs to be replaced for proper maintenance as per the manufacturer that built your car! The next time someone in the shop "recommends" a maintenance repair, whip out that owners manual and tell him to show you to back up his "recommendation". HA, you want to see some fancy dancing and back pedaling! I am willing to bet a weeks salary your original spark plugs are good for 100K. SO, Do NOT replace those plugs, go out to dinner with the money you saved, and while you're waiting for your food to be served READ THAT MANUAL!! GOOD LUCK
@@alblume3374 Thank you Al. I just saw this reply to my post from 2 years ago; and would you believe, 2 weeks ago I went in to get my NC inspection and there was a needs service light that came on between my house and the service place. They said I needed new spark plugs! So I spent $647 for them (they had to take something off to reach them and that added to the cost, gasket or something) just so I could get my inspection passed and renew my registration. I asked if that light could have been on since I hardly drive the car during the lockdown (working at home). Oh no, you need sparkplugs. I guess in 2 years when they say that and I've only drove 10 k or so I'll just pass. Thanks for taking the time to respond and you have safe and good day. Nancy
@@NancyGerst lol, Nancy, Don't think for even a moment that it only happens to people who don't look like they know what needs done & how to do it. I grew up with a bunch of mechanics in my family and we had a lot of mechanic friends. Until the mid 80's I pretty much fixed anything on my automobiles including engine rebuilds. I owned a late 70's Pontiac LeMans which occasionally stripped the timing belt and I had replaced it several times over the years. It normally took about 20 minutes and only required 1 screwdriver and a shop rag to accomplish. Early one morning I found myself far from home with a stripped belt, 1 new spare but no screwdriver or shop rag. As fate would have it I was broke down in front of the only mechanics shop for miles but hours before they opened. A deputy sheriff helped me push the car into the lot and gave me their phone number as well as a ride to my destination. I called them, they said they could put the belt on with no problem but it would be around lunch time before they could get to it. When I showed up after lunch I saw a mechanic was apparently still working on it. The car had a jack stand under it & a tire off as well as what appeared to be a puddle of fresh ATF under it. The mechanic was busily tapping a wrench in the right area under the car & referred me to the boss behind the window at the back of the shop. After greetings & introductions the boss said the mechanic was just finishing up & handed me the bill for $450. I asked him how much the hourly rate was for labor? He replied $50. I asked if he was really going to STIFF me for a towing charge even though the car had been parked right in front of the door where the work was done? He agreed that he should probably scratch that off which he did and handed me the $400 bill back. I took the top copy, folded it up & put it in my pocket as he objected stating he needed the original. I handed him the unreadable NCR copy along with $50 dollars and told him he could take me to court for the rest if he thought he could prove the charges to a judge. He declined. 😉
@@mikebarron5805 that sounds like a story my Dad, a truck driver, would tell. Thanks for the smile! Life is good, even during this pandemic, with folks like you willing to lend an emotional hand/smile. Have a great weekend!
I've read where plug manufacturers specifically state NOT to use anti seize on plug threads. I believe it had something to do with interfering with proper torque specs
Not sure you’re correct on the anti seize torque statement. I twisted a wrench for Cummins, and antiseized every thing that I might see again some day. I always went by torque specs and never pulled a thread.
On an older Cummings 855 if you torqued the head bolts with never seize you could crack the counter bore. That's one of the reasons they came out with water passage inserts. Torque values only apply with the specified lube
I service my own Harleys. On my old 74 sportster I service it every 5 thousand miles. On my new trike with the M8 engine I service it every 10 thousand miles. With the new synthetic technology I feel you could safely go 20 thousand. The main thing is that your synthetic lubricants be at their proper levels. I dont change plugs at all until the bike tells me it's time. If it ain't broke dont fix it.
Doc....thank you for all your tutorial & how to video's. Spark plug question. 2012 Street Glide,stock 103, just turned 40k miles. I use the factory recommended plugs. On recent 40k service at dealership,tech showed me my 5k mileage plugs installed at 35k service) and very top of outer electrode (ground strap),had white deposit. Bike always ran and performed very well. Center electrode had normal wear,no build up. I changed fueling station,but kept using 93 octane. Tech said cylinders and piston tops look good. Any knowledge on why top of electrode had white deposit? Oil migration? (piston rings? valve stem seal /seats? head gasket?) Should I request a compression test on each cylinder? Is it too much to change plugs every 5k miles now that mileage on bike is climbing?
Most all newer spark plugs from 2005 on up have an Iridium coating on the gap arm. Iridium lasts 10X longer because the metal can withstand 10X the heat than older spark plugs and why they first used them in MotoGP and is also why Harley changed the interval time to change plugs. I purchased new plugs for My 08 Dyna, Took the old ones out after 14k miles, they still looked bran new and I have no running issues so I didn't swap them out. Especially since with Iridium added to the sparks plugs they are 3X the cost of older plugs. SO yes they did actually change the design to the spark plugs. Now in 2024 all manufacturers use Iridium coated metal on their spark plugs, even on small engine plugs. Not a rant just an FYI. Video is 6 years old I know but allot of people don't know this info. Look at the box the spark plug came in, it will say Iridium coated...
Thanks Doc, any tips is good news. Have to go through your archival tips , if any, on the marvevllous V Rod. In particular the ' do I or don't I remove the air intake shroud ' dilemma. Cheers. Ed Queensland. Australia.
Thanks for the reply. I have read that through the removal of the V Rod air box it is possible to achieve a substantial horsepower increase. If so, my dilemma is how would one compensate for the loss of contaminent protection from dust particles that the current sealed system provides so adequately? The above insinuation seems to indicate that the current set-up restricts maximum air flow and hence a loss of power. Could you please throw some light on this theory.
I just changed plugs and wires yesterday. I went with stock plugs and Symax 8mm red wires. My 96 ci 07 FXSTC has a Stage 1 mod. I gapped the plugs to 38 as Doc recommended. Test ride was AWESOME. She definitely runs better and responded quicker. The plugs I pulled were about 43 so at the max gap. Thanks Doc for YOUR infinite wisdom!
I own an aftermarket shop...this guy is just good, I have my customers go to youtube while we are working on their bike.Plus he is articulate.
Doc, I know that I am a bit late to everything. I have a 03 fat boy. So I am new . I love it as everyone else does. I want to thank you for your videos. You are giving me a ton of information. No way can I ever thank you enough Sir!!!
Thank you for your support Dale....Doc
Your dad sounds like a smart man, he taught you well. Now you get to teach us a thing or two about Harleys. Great video Doc, see you next time!
Thanks 👍
It amazes me how many people don't know how to do simple maintenance. Thanks for helping the world be a little bit more aware of proper care of their scooters
Going to get spark plugs from the dealership right now thank you for sound advice and taking the time out to do these videos they greatly help us who aren't professional mechanics but can at least do minor repairs and upgrades
NGK, gapped at .040, change every 5000 miles. Cant go wrong.
There is nothing better than the stock oem plugs. But if I can’t get them, then ngk.
Great info. Thanks. Don't forget about the crush washer, needs replaced when you dress the plug and adjust the gap if you reuse the same plug.
When you change your front tire change your spark plugs too.Thanks for the information, it's right on.
Russell Linthicum this is true. I just bought a 2005 Sportster, with 11,000 miles on the clock, on the original front tyre. I’ve just replaced the tyre and the plugs too. Not too sure whether 15 years is a very good service interval though. 🙂
Thank you Doc, I was getting tired of different dealerships telling that it's normal on a 2 month old bike. 2021 streetbob with 8200 miles on.
When I first looked at the title I said, “Yeah, why change them”. I learned something!
As always, Doc, you are awesome. You make it seem so clear and sensible when you explain issues.
I appreciate that....Doc
Got 15k on my 2020 and haven’t had a single issue starting it, however it’s been in storage for 6 months (I’m deployed) so I went ahead and bought a new battery, spark plugs and wires.
Thank you for the explanation, I almost forgot about swapping them.
Thanks for sharing and watching our videos...Doc
Good info .Spark plugs can be cleaned and gap can adjusted. Riding for over 25 years. Plugs have never been a problem. I only had one ever fail completely. A little maintenance goes a long way .
.
Great point....Doc
My Ultra Limited was getting hard to start at 14,000+ miles. Initially thought it was the battery as it is the original battery on a 2016. Decided to put in new plugs and what a difference. Bike fires right up and the power on the road is back. I didn’t realize the amount of power loss the old plugs were causing. I’m going to go with Doc’s advice and replace the every 10,000 miles from here on out.
NGK spark plugs feature what is known as ‘trivalent plating’. This is a silver-or-chrome coloured finish on the threads that is designed to provide corrosion resistance against moisture, chemicals and weathering. The coating also acts as a release agent during spark plug removal. NGK spark plugs are installed at the factory dry, without the use of anti-seize. NGK tech support has received a number of tech calls from installers who have over-tightened spark plugs because of the use of anti-seize. Anti-seize compound can act as a lubricant altering torque values up to 20 percent, increasing the risk of spark plug thread breakage
Thank you for sharing this important information. I am concerned about steal going into aluminum without lube🤷♂️…Doc
It's not a bad idea to have some antiseize compound on the thread of the sparkplug, but you have to compensate for the torque-value. This is a good advice you gave. Thank you for sharing your experience and background story. 👍👍👍👍👍. Greetings from The Netherlands
Doc, thanks so much! My bike has had a hiccup every once in a while lately. I’m checking the spark plug when I get home
and survey said ?
Thanks Doc! Perfect timing, I’m changing my plugs on my Iron 883 this week 👍👍
Correct flame kernel without straining secondary windings is key! Good one Doc! ✌🏻
I really don't understand what you're saying could you expand on that
Wow! Got me thinking, 35,000 miles and don’t remember ever having them changes. Thanks
Jesus
Hey VN, when u take something (voltage) it's the same as receiving, Da. don't try to knock what this guy has to say. He takes the time, has the knowledge and his presentation is relaxed and positive. Thanks Doc.
Good video. I notice many Harley riders spare little expense on their "babies". Most NEVER wait until the mileage specified in the maintenance chart, yet every other machine they own they won't replace a part until it breaks. The arguments that "plugs are cheap", "cheap insurance", "why not just replace them?" makes little sense. If a spark plug cannot last more than 2,000 miles, you bought a crap plug!
In the video he refers to the fact that Harley has extended the mileage interval for spark plug replacement and that is for a good reason. "Doc Harley" states the plug is exactly the same. I cannot say with certainty that he is incorrect, but as an auto technician I know plugs have evolved immensely over the last few years. He is absolutely correct when he said the electrodes erode and the gap widens, but the metal which was used was steel or copper. THOSE plugs lasted 30,000 miles in a car. Today the mentality of plug design is to treat the 2 electrodes with platinum or iridium. These 2 precious metals are able to sustain much more abuse without wearing down. Sure, a 2 cylinder engine will fire the plug more often than my Dodge pick up V8, but come on, 2,000 miles!!!? I have much better things to do and remember than to change the Iridium plugs in my Dyna every 2,000 miles. If you're bored and want to "FIX" something on your scooter, check the tire pressure against factory recommended psi. I bet they need air.
He didn’t say change them every 2000 miles........he said 10,000 miles, big difference.
I was considering getting a more expensive plug but I will take your advice.
Thanks for watching Mike….Doc
Going on a trip with my 2015 road king. While checking everything the stock 6r12 plugs have about 10,000 on looked good but I had another set of fancy iridium plugs in the toolbox. Tossed them in and bike started better & idled better. Wasn’t even gonna change them but glad I did
Keep up the great work on all these videos Doc!!! Great feedback, we appreciate you boss 🫡
Doc I could not have said it any more clearly. Perfect, plus check your wires for being dried out and the boots over the plug. I alsways change them out at 10K but i use NGK and changed out to Harley Fat Wires. Tech tip...carry a spare set in your bags...what $15.00 to save headaches. No brainer
I normally change my spark plugs every 1500 miles or 2000 depending if I'm getting ready to head for bike week. I bought this little case that holds two spark plugs. I have three of them and when I change my plugs I put the old ones in this plastic case. That way if someone else riding with us has an issue I have spark plugs with us so we can get back to riding. The only stuff that I use on my bike is Harley-Davidson parts. I'm not going to name aftermarket brands that I try at the beginning when I purchased my first Harley. The parts that these aftermarket people sell just do not have the same quality that a Harley-Davidson part has. I use their spark plugs I use the oil when I change lights it's always Harley-Davidson.
Great video a lot of people just do not think about their spark plugs. Even with the frequency of me changing my plugs I can feel a big difference the next time I ride my bike.
can you tell me where HD. makes their oil ? I don't think so.
He's like the Alton Brown of Harleys
Spot on dude
Doc your old man was a smart dude. Thanks again doc
Excellent explanations Doc! That'll keep it runnin right. 👊
Yes sir great tip . I change mine every year at beginning of the riding season .... I live in the north ....lol
Yep do the spark plug replacement at every oil/filter change too 👍
Check plug tops, make sure they are tight. Anti seize threads, and a little dielectric grease on plug top and a little in the boot for ease of slip on. Champion Spark Plug Chart shows you how "Spark plugs tell a story", you can find them online, or buy one and stick up in the garage.
A good follow up Tech Tip….Doc
Great advise... this video gives you great details on the basic spark plug install . .little steps in this video add up to the proper install . . . no more ' hick' ups'.... thank you
My own experience on my 2007 Ultra I installed true duel exhaust, Vance and Hines mufflers, high intake air and with this a Fuel pack. I have found that between 6 to 10 thousand miles my check engine ligh comes on and takes longer to go off. When I change spark plugs this remedies the problem. Change Spark Plugs Spark!!!
I know it’s a 2 year old video but just wanted to add according to the service interval per manufacture specifications on my 15 Road Glide 103HO it’s replace spark plugs every 2 years/30,000 miles which ever comes first. Yes I strongly agree with you keep it simple what you take out is what you put back in .... unless your doing major engine modifications such as altering the compression, etc than it starts to matter.
Doc Harley, One thing you did not discuss was resistor spark plugs. They have a built-in gap also in the ceramic stem. You can’t see that but that gap also wears down and gets round. I usually change mine every oil change. They’re not that expensive and I ain’t doing anything while I’m waiting for the oil to drain.
My bike has 9k miles on it. Just added a S&S cam and a Vance and Hines exhaust. Been having a very hard time getting it tuned. Pulled the plugs and the gaps were closed (under .020) not sure how that happened but she runs much better with the proper gap
Hi Doc I agree with you, especially for people changing their own. Better performance for less than the price of a value meal, why not? My only thing is my bike has NGK plugs and after talks to NGK they told me no anti-seize because their plugs already have a coating. So I would say check to see if your plugs have a coating before adding anti-seize, could cause you problems over torquing the plugs
You are very logical and dead on accurate
Hey Doc
Would you mind doing a video explaining the improvements made in the 2024 M8 engine, if any, regarding crankcase breathing and oil getting to the pistons, you’re knowledge, and advice is greatly appreciated
Thank you for sparkplug tips. My 103 has a stage one kit currently which has been tuned at Harley Davidson so I recently changed my sparkplugs on my 2015 Ultra Limited to Screaming Eagle sparkplugs and also upgraded my plug wires to the Screaming Eagle plug wires. Hoping for a little more performance until I go to the next stage 2 kit.
One additional comment to spark plug changing is to not over-tighten. It's easy to do. Best is to check the service manual and use a torque wrench. CAUTION: if you use anti-seize as Doc recommended, the torque value in the service manual DOES NOT APPLY. The torque values in the manual are for clean, dry threads with only the oil from manufacture. Anti-seize will cause much higher thread loads by the time the torque value on the wrench is met.
And ..with the extreme heat the anti seize can get down into your cylinder heads not a good thing.. I base this on car racing if you want your plugs to foul extreme temperatures put some anti seize on them
You're taking about New Plugs and the Gaps. Took the plugs(Factory) out of my 2018 1200 Custom. Checked the gap. One cylinder was at .035. The other at .040. Only 200 miles on Odometer. Replaced them with a set of NGK Iridium. Found over the years the Iridium last longer. Ran a set of NGK in a Street 750. 10k Miles and no wear. NGK said not use Anti Seize. It affects the Ground. And the oil runs down the heat sink.
Great tip Doc. plus spark plugs (not talking about the ones that are hyped to boost your HP rating by 50%, or they are so intense they would ignite space shuttle fuel) are so inexpensive, would only make sense to put in new plugs even at 6 to 8 thousand miles. Your Harley's worth it!!!
may I add one thing to this. When you change your plugs use a torque wrench and set them to the proper torque.
and Use anti seize on every spark plug
I have to say. Doc makes a lot of sense.
Good information. I change my plugs every 10K miles whether they need it or not. I think my service manual for my 2016 HD Streetglide Special says every 35K miles which makes no since.
Agreed ,for all you young guys out there ,try starting a kick start 6 volt
FL Panhead with bad plugs .
Been there, got the T-shirt and larger right calf.....Doc
My service manual says change at 20K - My dyna is at 10K right now. I suppose I should check/change my plugs based on this video. Thanks Doc.
Great tip, with common sense. The good old school tune up: Plugs, Oil and Filters. I suppose we have done away with points by now but, My old 1980 FXRS80 had points.
Doc Holiday dude is cool 😎👍🏼🏍
Great tips !
They are $4-$10 bucks each depending on brand and where you buy them. Personally I buy the HD silver and change mine with every oil change. But I also ride my bike almost every day, year round. Take care of your ride and it will last longer.
When I was in auto shop on high school (1000 years ago) I was assigned to rebuild an old Maytag GAS POWERED washing machine engine. The spark plug was dated 1918 and it was a fat little guy. Here's the big thing; it had a little 8-bladed fan on the bottom, NOT the typical spark-gap thing (I'm sure there's a name for it but I don't know what it is) like today. Have you ever seen a spark plug like that? BTW, I had to use it and it still worked like it was brand new!
Thanks for sharing. I have a few unique spark plugs but none with a fan…Doc
Great video and advice. Plugs every 10k miles is cheap insurance. Use the OEM plugs.
And do not go to hotter range spark plug tips if your riding style is mostly average speed with the usual blasts for kicks. Like the man said, the lower end of the OEM gap is better.
Here's why I disagree with a 10,000 mile spark plug replacement.
1. Engines run closer to the stoichiometric A/F ratio, so plugs stay cleaner.
2. Modern engines have higher ignition voltage, making for a hotter spark and easier to jump the gap.
3. We no longer use lead in the fuel, and fuels are better than those of years past.
4. Engines are better built and have lower blow-by minimizing oil burn and resultant plug contamination.
I change mine at 50,000 miles...never a hiccup.
I over looked changing my OEM spark plugs at just under 69K miles. I didn’t notice any performance issues on my then 110” 2015 CVO motor. I plan to change them at 20K miles from now on.
Heres my advice to harley owners. Have a pouch or use your saddle bags and keep four new spark plugs and a ratchet and socket in any harley you use. When you start them cold and one cylinder doesnt fire until it runs for 10 seconds (which is common), change the plugs. Some will miss out and you have to keep reving them when theyre cold, change the plugs. For the record I have had the best luck with auto lite spark plugs. You have to cross reference them to know what size, as my twin cam uses a different size than my evos. Always also be sure to compare the reach of a plug with the old plug, because if your reach is longer you can knock a hole in a piston top or if too short can result in carbon. Also, keep a round plug gap tool on your key ring, so you can gap them
Earl it sounds like you could write a book on the knowledge you have gathered over the years of riding. Thanks for sharing..Doc
@@LowCountryHarleyDavidson Havent learned that much about the M8 yet though. But from what Ive seen I think the M8 version appears better mechanically than the TC B version due to gear to counter balancers instead of the guide and chain
grate advice .. spark plugs are so overlooked now days.
Doc, thank you for your video. They are an excellent source of sound advice. Keep them coming.
i change plugs every fall when i put the bike away for winter (OHIO) along with all
three hole of oil....put on about 6K a year....good insurance...
Excellent... Thank you sir 👍🏾
I have a 2015 Limited Low. The owners manual says change every two years or 30k miles, whichever comes first.
Iridium plugs have an anode and electrode so hard, they don't wear nearly as fast. Their gap stays constant. Also, torque down your plugs properly. My 1200 Sporty starts right up, cold or hot.
Thanks for sharing your experience….Doc
Priceless information, as is your custom Sir. However, I was put off by the increased change interval HD recommendation…it should be shorter than 10K. If a 10K plugs is in such a condition that a simple visual inspection confirms, “definitely needs replacing” then it stands to reason, that a shorter interval is warranted. “PMS” in the U.S. Navy means, Preventive Maintenance System, the thought 💭 process is to KEEP equipment AT peak level performance while heading off failure. Doc, in my humble opinion PMS applied to HD spark plugs would suggest a 5K inspection and/or change. 2020 Fat Boy
You are so correct....Doc
I change my plugs every spring then halfway through the riding season, 2 oil changes @ 3500 miles each.
Wow……Doc
Great advice.
Thanks Doc I have a 2019 triglide the reverse stopped and I watched your video and reset the breaker it works fine thanks Joe in Valdosta Ga.
Trikes are the way to go ! I swore I would never ride anything EXCEPT an Electra Glide. I just bought a 2019 Freewheeler and I've never looked back. Motorcycling is fun again and I feel much safer. Especially with my lady on the back !
I appreciate your videos Doc!
I appreciate that..Doc
I'm watching this thinking about my car engine, way newer tech and way more power per cc than my HD.
Changes the plugs every 10 yrs, car runs fine on cheap ethanol gas, get awesome mileage.
I just put some iridium plugs in my bike though:) After 7.000 miles and the original ones looked fine.
Well, maybe I should take this video down 🤔. Your facts are outstanding…..Doc
@@LowCountryHarleyDavidson I apologize for making an observation and expressing my doubts as to whether or not a spark plug is worn out in such a short service life.
such an informative video, I needed this info.
thank you sir !
With the price of gasoline and the price of parts I change my spark plugs every oil change at 5000 miles and always check the gap
Getting on it today
Good info for many. Thanx
Thank you Gremlyn….Doc
My comment isn't about this video. Supposedly about 5 years ago Harley did a recall on their saddle bags because they just fell off! Fast forward to today I'm reading forums with people who are losing their bags. I think this is a bit of a liability to harley. I think people who lost a bag should form a group to pressure HD to replace the pins with a different mechanism and compensate people the money they spend replacing them. What is your opinion about this. If it was fixed and they are still falling off, it's not fixed. What if one flew off and killed someone? Who would be liable? Something for them to think about.
The reason they increased plug change intervals is the same reason they increased fluid change intervals.
It reduces cost of ownership.
I still recommend plugs @ 10k, engine oil @ 2500 and primary and trans fluid & 5k.
Lubricant quality has improved over time so people argue “ it doesn’t break down as quickly” but changing oil is about removing contaminants more so than oil breakdown. Contaminants come from internal component wear and corrosive chemicals introduced from the combustion chamber.
Great presentation and advice.
Good monning Doc-Harley 👍. Have a blessday. 👀👂
We appreciate the blessing....Doc
How about Not using spark plugs at all? TCB (Traction Controlled Braking) out of Texas making head gaskets with 4 spark igniter giving no loss of spark from plug (no plug puts a bolt in spark plug hole just to close it off) an better circular cylinder firing with 4 equally spaced computer controlled sparks, Very Cool! P.S. his braking system for motorcycle great too!
Okay. Change plugs at least every year, so do it when I change the battery in my key fobs, on my birthday. 😎
Love your videos… 🔥🔥🔥changing mine this week jus hit 10k
Pick up new plugs today at dealer and they had to stock wires because they carry them in so he then try selling me screaming eagles at $30 I said I'll wait for the stock he thought I was weird but I didn't care I'm starting not like that dealer
Awesome video Doc. I have a question. I have a 2022 Harley Davidson XL883N Iron 883 and was wondering what brand or name of spark plug should I be using in my Iron 883 and what should be the gap?
Go to your local dealer and buy genuine HD Spark plugs. Gap .038-.042….Doc
Just to add I use either dbl platinum or iridium plugs because they last a longer in whines in good cond using little or no oil between oil changes. If your motors tired no plugs will last as long because of oil burning build up if carbon etc on the plugs causing you yo have to change them earlier.
Thanks for the Tech Tip....Doc
...and no cross threading when you screw in your plugs.
Great video! Learn something everyday
Doc, I pu a 2003dyns wide glide with 50+kmiles. I am changing the plugs. But, should I also change the plug wires ? If so, what kind would you recommend?
Thanks for your experienced help.you help us hd bike riders so much.
Yes, If your bike is carb go with Magnacore or Taylor if your bike is fuel injected go with HD factory...Doc
@@LowCountryHarleyDavidson thanks again doc.
Got nearly 70000 miles on the original plugs. Big believer in adding Marvel Mystery oil to the gas.
I been messing with that since I was 18 ,im 40 and still use that stuff!
my honda has just gone over 80000km no problem with the first set. i still don't see a reason to change it if it starts and runs perfectly. maybe at 100000 ill change them
on my race engine i replace plugs every 600 miles... this is a must...
Are they surface gap plugs
I got 23,500 miles on my RG
Never Changed yet 😳
My Dealers never told me to change
They Perform all Services on my Bike since day One , Never Changed
Very Sad
Many follow HD recommend 50K change.
Me….Really?…..Doc
What about , "Heat Range" ? For hot and cold , riding days ?
With your knowledge I am guessing you used to race? A company chooses an average heat range that works in most applications. Once you change the dynamics of your motor then choice is important….Doc
Thanks for this video. My Buick dealer recommended changing the spark plugs on a 2011 Buick LaCrosse, 6cyl, with 87k, and wasn't sure I needed to do that, so I postponed it. I know, I know, this is a HD video, but what you say related to what I'm experiencing. Thanks again!
Nancy, NEVER take a service person's suggestion without doing your own research. I was an auto dealer technician for over 30 years and I have seen SO many dishonest people sell "stuff" to uninformed customers it made me sick. I know a slimy service manager in a dealership who actually told customers every spring they need to drain their anti freeze and install coolant. Then in the fall he would tell the same customers they need to get that coolant out of the engine and install anti freeze!!! Anti freeze is simply another name for coolant. They are the same thing and for the last 20 years or so, new cars come with coolant which is good for 5 years!! When you bought that car it came with an Owners Manual in the glove box, you know, that little book which is STILL wrapped in the cellophane. lol Near the back of that manual you will see a "Maintenance Chart". That chart will list EVERY part which needs to be replaced for proper maintenance as per the manufacturer that built your car! The next time someone in the shop "recommends" a maintenance repair, whip out that owners manual and tell him to show you to back up his "recommendation". HA, you want to see some fancy dancing and back pedaling!
I am willing to bet a weeks salary your original spark plugs are good for 100K. SO, Do NOT replace those plugs, go out to dinner with the money you saved, and while you're waiting for your food to be served READ THAT MANUAL!!
GOOD LUCK
@@alblume3374 Thank you Al. I just saw this reply to my post from 2 years ago; and would you believe, 2 weeks ago I went in to get my NC inspection and there was a needs service light that came on between my house and the service place. They said I needed new spark plugs! So I spent $647 for them (they had to take something off to reach them and that added to the cost, gasket or something) just so I could get my inspection passed and renew my registration. I asked if that light could have been on since I hardly drive the car during the lockdown (working at home). Oh no, you need sparkplugs. I guess in 2 years when they say that and I've only drove 10 k or so I'll just pass. Thanks for taking the time to respond and you have safe and good day. Nancy
@@NancyGerst lol, Nancy, Don't think for even a moment that it only happens to people who don't look like they know what needs done & how to do it.
I grew up with a bunch of mechanics in my family and we had a lot of mechanic friends. Until the mid 80's I pretty much fixed anything on my automobiles including engine rebuilds.
I owned a late 70's Pontiac LeMans which occasionally stripped the timing belt and I had replaced it several times over the years. It normally took about 20 minutes and only required 1 screwdriver and a shop rag to accomplish.
Early one morning I found myself far from home with a stripped belt, 1 new spare but no screwdriver or shop rag. As fate would have it I was broke down in front of the only mechanics shop for miles but hours before they opened. A deputy sheriff helped me push the car into the lot and gave me their phone number as well as a ride to my destination. I called them, they said they could put the belt on with no problem but it would be around lunch time before they could get to it.
When I showed up after lunch I saw a mechanic was apparently still working on it. The car had a jack stand under it & a tire off as well as what appeared to be a puddle of fresh ATF under it. The mechanic was busily tapping a wrench in the right area under the car & referred me to the boss behind the window at the back of the shop. After greetings & introductions the boss said the mechanic was just finishing up & handed me the bill for $450. I asked him how much the hourly rate was for labor? He replied $50. I asked if he was really going to STIFF me for a towing charge even though the car had been parked right in front of the door where the work was done? He agreed that he should probably scratch that off which he did and handed me the $400 bill back. I took the top copy, folded it up & put it in my pocket as he objected stating he needed the original. I handed him the unreadable NCR copy along with $50 dollars and told him he could take me to court for the rest if he thought he could prove the charges to a judge. He declined. 😉
@@mikebarron5805 that sounds like a story my Dad, a truck driver, would tell. Thanks for the smile! Life is good, even during this pandemic, with folks like you willing to lend an emotional hand/smile. Have a great weekend!
@@NancyGerst Glad I could help in even a small way. 😁🙏
I've read where plug manufacturers specifically state NOT to use anti seize on plug threads. I believe it had something to do with interfering with proper torque specs
I need to find this. I can’t believe putting steal threads into aluminum heads doesn’t need some kind of lubricant….Doc
Not sure you’re correct on the anti seize torque statement. I twisted a wrench for Cummins, and antiseized every thing that I might see again some day. I always went by torque specs and never pulled a thread.
I drop the torque value by 5 -10 with anti-sneeze.... done it for years on cars, truck & tractor engines and Never fouled a plug with anti-sneeze...
On an older Cummings 855 if you torqued the head bolts with never seize you could crack the counter bore. That's one of the reasons they came out with water passage inserts. Torque values only apply with the specified lube
Thank You Sir
Most welcome….Doc
I service my own Harleys. On my old 74 sportster I service it every 5 thousand miles. On my new trike with the M8 engine I service it every 10 thousand miles. With the new synthetic technology I feel you could safely go 20 thousand. The main thing is that your synthetic lubricants be at their proper levels. I dont change plugs at all until the bike tells me it's time. If it ain't broke dont fix it.
Have fun changing the 4 on the m8 touring models. Be careful taking that fuel tank off.
Good advice…Doc
Doc....thank you for all your tutorial & how to video's.
Spark plug question. 2012 Street Glide,stock 103, just turned 40k miles.
I use the factory recommended plugs.
On recent 40k service at dealership,tech showed me my 5k mileage plugs installed at 35k service) and very top of outer electrode (ground strap),had white deposit.
Bike always ran and performed very well. Center electrode had normal wear,no build up. I changed fueling station,but kept using 93 octane. Tech said cylinders and piston tops look good.
Any knowledge on why top of electrode had white deposit? Oil migration? (piston rings? valve stem seal /seats? head gasket?) Should I request a compression test on each cylinder?
Is it too much to change plugs every 5k miles now that mileage on bike is climbing?
Most all newer spark plugs from 2005 on up have an Iridium coating on the gap arm. Iridium lasts 10X longer because the metal can withstand 10X the heat than older spark plugs and why they first used them in MotoGP and is also why Harley changed the interval time to change plugs. I purchased new plugs for My 08 Dyna, Took the old ones out after 14k miles, they still looked bran new and I have no running issues so I didn't swap them out. Especially since with Iridium added to the sparks plugs they are 3X the cost of older plugs. SO yes they did actually change the design to the spark plugs. Now in 2024 all manufacturers use Iridium coated metal on their spark plugs, even on small engine plugs. Not a rant just an FYI. Video is 6 years old I know but allot of people don't know this info. Look at the box the spark plug came in, it will say Iridium coated...
I will look at this. Please send information and reference to my email so I can learn….Doc
Nice and to the point. 👍
Thanks Doc, any tips is good news.
Have to go through your archival tips , if any, on the marvevllous V Rod.
In particular the ' do I or don't I remove the air intake shroud ' dilemma.
Cheers. Ed Queensland. Australia.
I am lacking in the V-Rod videos. If you have any suggestions please send to my Email…..Doc
Thanks for the reply. I have read that through the removal of the V Rod air box it is possible to achieve a substantial horsepower increase.
If so, my dilemma is how would one compensate for the loss of contaminent protection from dust particles that the current sealed system provides so adequately?
The above insinuation seems to indicate that the current set-up restricts maximum air flow and hence a loss of power. Could you please throw some light on this theory.