This old dog has learned a new trick! After reading motorcycle plugs for decades, earning respect from my peers. I feel this video has been the most informative piece of proper tuning information I’ve ever been lucky enough to come across. Mr Baxter thank you so much for sharing your knowledge and time with us. I’ve been missing half the story plugs have been telling me.
I just wanted to thank you for the videos you have posted on RUclips. I've been doing this for almost 40 years now and you're the most knowledgeable Harley Davidson mechanic on the Internet. You look at things from a different perspective than the average wrench and it all makes perfect sense. Keep them coming and Thanks for the help.
Macro photography is always difficult. Because the depth of field becomes shallow. This is also true of video cameras and even harder to manage with video.
I raced motorcycles for 25 years and I just learned things I wish I'd known years ago. What's particularly great about your style is you not only explained it, you connected enough dots that what you showed is logical, and remembering the concepts you can figure out what it should look like. That's great teaching. Thank you, I'm subscribing after one video view.
I can't believe this clip comes up today. The very day my bike tuner who's is doing a build for me was talking about reading plugs & your name came up as you were the first to comment on hos post. Brian from EASTERN BIG TWIN. Australia. G'day 😉👍
Wholly shit, and I thought I knew my mechanical skills to work on my own Harley, this video just threw all that out the door, what an amazing informative educational video I just watched, out of all the tech videos I have seen, this is by far the best I have seen, thank you Kevin, 👌👍
@@KevinBaxter the only thing you missed was cold rating. Other than guessing, is there a way I can tell if i have the correct plug. If you don't know i run a turbo road king w/98" that runs 30lbs boost (not a typo lol) currently running ngk's dcpr9e
No doubt there sir. As you know, much of that can change a little when dealing with boost, nitrous, alcohol, nitro, etc. I didn't even go there on this one because very very few people take things to that level and I didn't want to confuse anyone. 30lbs boost...just how big are those cyl studs? lol. Anyway, to answer your question...in a boosted engine you can also use the ground strap as an indication of plug "temp". You would want the color change in the exact same area however, if you aren't experiencing detonation and you know the timing is pretty dang close, use that to determine if you could run a hotter, or colder plug. If the color change is close to the tip, run a hotter plug. If it's closer to the threads, run a slightly colder plug. You want in right in the middle of the bend. Also, pay very close attention to the center porcelain. If it starts to look glossy....as if its melting, definitely run a colder plug. Hope that helps.
@@KevinBaxter if you find yourself with some extra time on your hands check out the road king, I have a few video up here on the tube of it. I built it last year from the ground up, started with a bare frame, no parts no motor nothing acquired it all for the build and did it for about 15k total investment, you will see the progression of me turning up the boost, I started out 12lbs then went to 18lbs, then 22 and then just let it eat at 30lbs, i think i can make even more boost yet, it sounds like a 2 stroke chain saw going down the track. I've been doing all the tuning with some help from my local HD'er setting the AFR's and making sure i don't run into spark knock. By the way I swear by Kimbal White studs, wont ever use anything else.
Mr. Baxter the information that you give is is so educational on a real level you always keep it straightforward facts factual and I appreciate you giving your time up to help all of us out here become better writers and better tuners God bless you..
Well he picked up another subscriber I've watched couple other videos and doesn't ever suggest taking the bike to the dealer he's a VERY GOOD PERSON to learn from
WOW! I’m going watch again with a note pad. This has been black magic for years to me. Never found a good explanation on the process of tuning from spark plug color. Thanks for the great info!
Thank you sir. Be sure to watch the follow up video where I applied the same principals to the 270 inline 6 in my 1949 GMC. I call it the "Stovebolt" project.
Mr Baxter, not since I was in Auto Shop have I found some one like yourself that provided a really comprehensive explanation, your an excellent teacher, must be hell of a mechanic. I am now a subscriber to your channel.
@kevinBaxter this is the most advanced explanation I’ve ever been able to find on reading plugs outta Harleys. I learn so much from watching your stuff man. Can you do another video some time reading a larger array of ‘bad’ plugs? I still have so many questions on plug conditions I’ve seen and I know there’s more to learn. Keep it up brother, your channel is the best you are definitely the guy I want to learn more about HD engines from. The attention to detail and breadth of knowledge and experience you have is so hard to come by. And just straight up professionalism and craftsmanship. I love it you’re my kind of people man keep it up !! ✊🏻
excellent Kevin. I sure did not know plug reading to this level. Just the ceramic coloring to tune the carb jets to the new carbs/pipes, etc. Worked just fine for me in the 70's on 2 and 4 stroke bikes.
I built a 1974 year Shovelhead all stock. Later I has a 1980 Shovelhead with a mild cam and S&S B carb. My Toyota tech friend told me to run Toyota plugs. So for all those years I ran the ND-16 U-groove Toyota plug. Also a great plug against seizing in the head. I never had one to foul out and always ran clean. I also ran them in my 1994 Heritage Evo with crane 490 cam and S&S E model carb. Great plug. In my 2010 Heritage, I was going to try them and for some reason, the 2010 Twin cam engine has some off the wall thread diameter that the parts store could not cross reference. I run SE plug in it. Oh Well
Kevin never considered the amount of information a spark plug could reveal. I figured if it wasn't fouled we are good to go. Thanks for the education. Always fascinated with the true inside stories, nice presentation.
I have a 1974 shovel with lots of head work including bigger inlet valves, an S+S big bore kit, C grind cam and dynamically ballanced crankshaft and it goes realky good, nearly as fast as my 1999 twin cam. About 20 years ago i gave it a full service ready for an interstate run with my club, then it was hard to start coz i took all the electric start off so kick only and it always started 1st kick hot or cold, but then it would take 20 kicks to start, so i pulled the spark plugs out and cleaned up the old ones and put them back in and it started 1st kick again, so i looked at the numbers on the new plug and they were the same except for a R at the end of the number so i took them back to the store and they told me that the EPA made a rule that all plugs had to have a resistor in them to cut down radio interference so i hunted around and couldnt find any plugs without a resistor in any brand of plug, so now i am using the old plugs and have been using the same plugs for 35 years, and just clean them when i do a service. I found split fire plugs and they worked for a while but they went out of buisness years ago and coz they are split fire it made them hard to clean so back to the old Bosch plugs. I have points in the ignition so i can presume that resistive plugs would work with electronic ignition but my mates with electronic ignition and kick start only all have trouble starting. So my question to you is do you know of any spark plugs that dont have a resistor in them. Appreciate any help you can give me on this subject. Johnny
Great video, i tuned My 2013 Streetglide D&D Fatcat exahaust with the DynoJet Powervision but without O2 Sensors and adjusting all fuel setings manually. I just raised the fuel up a hair and rode a little and kept bringing it up based off how it was running and reading the plugs, I just went on a 3200 mile trip out to Utah, rode in 100 degree heat and 12,000 foot up in Colorado, the bike ran great and when pulling a plug after i got back i expected to see signs of riding in the heat but the plugs looked great based on your video here, just a slight color change 2 threads down, i actually raised the fuel up a tad after all that since they looked more grey where ypur showing more black but the center porcelin is still white. This has been a lot of fun and i no longer hate fuel injection and think this actually works better then a carburator. Your video taught me enough to get it runing perfect. One thing you cant teach though is common sense, you will need that to tune this way. A lot of people are hard headed and refuse to learn, in there case they're better off to just use a pre tuned map or whatever you call that or pay a Tech. I like the hobby aspect of doing it myself.
I have to say that even though I can read a plug very well, this is the first time I've heard of taking the porcelain out to get an accurate reading of the throttle range.. It's was the only way I had to set up my card at the drag strips... It was not uncommon to go through 6-8 sets of plugs in a day... I will say though that I also have a Wego III exhaust gas analyzer with data recording... Great tool.. Well Done.. Thank you...
Dear Kevin i'm a new subscriber just really diving in to harley engine dynamics. I love what you are doing to educate the average, and experienced cycle enthusiast. My only complaint, and not a huge one, is this video specifically needed to have the focus of the camera dialed in a little better. The closeup was just fuzzy enough to make it hard to see what exactly you were trying to show.
Welcome aboard! THanks for the kind words sir. I agree. That close, the camera auto focus on macro doesnt work very well. i did a follow up here....a little more clear. Thanks for the sub - ruclips.net/video/bIS28KRT4AY/видео.html
Kevin, Nice to see a real technician giving advice and explaining what is going on. You certainly separate yourself from 90% of the "so called mechanics"...Im having some problems with my 03 Road King and would love to get your advice on what might be happening...would you be willing to help me and if so can I write to you offline of youtube.???
I have a 2001 twin cam and after watching this video I thought let’s go see how my plugs look! So the rear plug looked great but the front was all black from carbon power, so what am i having a huge difference in cylinders? Great videos very educational!!
Great info. Don't own a Harley yet, but I see one in my near future. Am amazed at all of your content. Have one question if anyone would answer. He lost me when he mentioned the 12.8 to 13.2.
Thank you sir, been waiting for info like this. Re jetting a S&S 96 and always ran rich. Ran good but always black plugs. With gas with higher octane, like 110 I had a chocolate color. Always ran poor in low rpm. Finally re jetted the carb and with 91 octane I'm getting a nice cocoa color and a lot more torque and better throttle response. And always wonder if my timing was correct. After looking at my plugs and still wondering if I'm in the right area, I saw this video. I think I feel better knowing that I'm pretty close and shouldn't have to worry about blowing up an engine. Great content!
Kevin, new subscriber here in Canada. Absolutely fantastic channel with professional on-point info (I’ve watched them all) and great presentation. I’ve done about 15 twin cam builds and 1 M8 (all in my home garage) and must say that your knowledge and experience is invaluable. My tablet and your guidance will forever live atop my tool box with my shop manuals for easy reference. Keep up the great work Kevin.
Kevin Baxter Up in Kingston, Ontario. 25 minutes and directly across from upstate New York border. Ride the New York, Pennsylvania, Virginia, NC/SC states. Haven’t been to GA yet but plan to. Would love to drop in once things open up. Be well, be safe and keep us all fed with your great knowledge. Thx.
I love Kingston. Know the guys at Motosport Plus...well I did until ownership changed anyway (Tony Hewitt used to work there...good fella). I went up there a few times to train them on EFI tuning. You probably know of Bob McKay...McKays cycle creations. he was a very very dear friend. Wayne at Heritage Cycle Works....great friend as well. I actually have a few boxes of pucks from Canadian Tire bought from the Kingston store. I use them as feet on my equipment. Actually the first time I had a Timmys was with Bob, his wife Dianne, and my wife in Kingston several years ago. Hard to beat a Timmys. I was just up there a few months ago...I drive up and cross over by way of the 1,000 island bridge. Have also judged the Toronto bike show a few times. If you find yourself near Ga...welcome to come by anytime.
Great content! Question? If the color change is in the curve of the ground strap, that indicates proper ignition timing. But, is this proper ignition timing at cruise RPM where the engine spends a lot of time or does it cover the entire RPM range considering different RPM’s and engine loads require different amounts of ignition timing advance? Thanks
Great info. Thanks. wonder if chalk on the ground strap would help even more to recognice good ignition. Hard to see on my spark plug. When i cut with oxygen and acetylen i use chalk to follow where to cut. And the chalk would not burn of. Maybe that could be a help to see about the ignition. My engine is an 106 TC stroker. with a high correct compresson ratio. About 9.7:1. So im trying to get air/fuel and ignition as perfect as possible. Im using octan booster. Thus hard to check the ground strap. Dave Mackie heads and TC G 590 camshafts. Pulls very hard. Im living in Sweden. Thanks for your thoroughly teaching. Greetings Peder
Great work. Love your detailed look at the colorization of the plugs. I learned a lot and hope to apply it to my resent engine mods and dialing in timing and jetting. Thanks you very much h.
5:46 this part of the spark plug you're pointing at: on mine it appears stained on one hemisphere -meaning, on some spark plugs the stain has a crisp border where its coffee hue ends and the normal porcelain color begins, but on others it looks fuzzier like powder fouling. Any thoughts on what that can mean? Anyways great video, one of the most detailed overviews I've found yet!
Excellent video; and very helpful as I get ready for some tuning. I'd like to start with making sure I have the correct heat range plug for my application, can you offer some advice on how to determine this, or how to contact someone for help?
Wow...great video. Excellent explanation. And you're right, reading plugs is a lost art, but they can tell you exactly what's happening in your combustion chamber. Thanks again.
Best Spark plug reading video I have come across by far, thank you. But how do I tell the difference between a spark plug that is overheating due to lean mixture or a too soft a grade plug without examining the Combustion chamber?
Thank you sir. if lean, you will see the white residue on strap and center porcelain. If heat range you will typically see the porcelain turn glossy...as if it's melting.
Ok, great vid. After putting in new plugs, how long do you run the engine before pulling them out to check the tune? Im talking about a street bike running normal fuel under normal conditions. I'm also referring to the fuel mixture, not the igntion timing as I know the ignition timing mark will appear straight away.
A hack saw blade and a cordless drill makes short work of the spark plug crimp. And if anyone knows the part number for a ngk dcpre 7 plug without a screw on top I would appreciate it. The only advantage I’ve come to with HD is being able to run the fine line of detonation due to a roller bearing crank. Swain tech coating stops the pistons from being wear items in high compression pump gas hot rod bikes. Fine video sir, you give insight to why we make the big bucks🙁.
Awesome video as usual.... Is there a service that one can send your plugs to get a reading of what's going on? Maybe spot some red flags early? I have a 2010 heritage classic. Stage 1 with a Thundermax tuner and D&D exhaust. I started with the tuner cause I knew I'd need it anyway when I finally got to the exhaust. Bought the tuner thru Cycle Solutions. They sent me the initial base map and then a new map once I added the exhaust. I pulled my plugs after watching your video and they looked nothing like those in your video. No black at all, crusty light deposits all over the ground strap, the outside of the center electrode and even thicker on the porcelain...... So, to put it mildly, I'm concerned. The bike runs like a bat out of hell.... so no complaints from that aspect.... But if I've learned one thing from you; An engine can be self destructing slowly with not symptoms until it's too late..... Don't want to end up there......... Any suggestions where I might turn to for help reading my plugs.
I just recently changed spark plugs, I believe that the ones that I took out were original because they said Harley-Davidson on them and the bike has about 24,000 miles on a stock '05 Dyna Wide Glide fuel injected Twin Cam 88. I wished I would have kept the old plugs so that I could have tried to read the other aspects of it but I threw them away. The plug from the front cylinder had a lot of carbon build-up on the electrodes, so much that the gap was almost completely closed but it wasn't shiny or wet. The rear plug had quite a lot of carbon build-up also but not as much as the the front. The engine had been missing mostly at cruise speeds and also popping from time to time on deceleration. I replaced them with NGK Iridium IX DCPR7EIX spark plugs and it runs great. I also changed plug wires but went back to the originals for now because the new ones were a kit that I put together and they were causing the check engine light to come on. I think I may have damaged one when I was trying to pull the spliced end off of one, I'd forgotten to cut it to length first and twisted it a few times, probably damaged the core wire. Anyway, I'm curious if that much carbon build-up is normal after 24,000 miles or if something is off.
That's not normal at all. Could be excessive rich mix or oil blowby. Id be doing a leak down and cyl pressure test on that one. Also...valve stem seals were a common issue in that era.
This was an awesome video! I have a dyno at my house and I've tuned a lot of high horsepower nitrous bikes (Hayabusa zx14 gsxr1000 ECT) but I've mainly used the grounding strap just for finding out what timing a nitrous motor likes. I'm going to buy something to where I can cut plugs open and I'd love to compare this method with the wideband on the dyno. By having a cheat sheet (AFR wideband) I should be able to see how close my initial guesses are when reading a plug. Can't wait to try this out with one of my personal bikes
ive done it long enough, i can almost tell you to .2-3 afr what it is by reading the plugs. you will start to see the pattern. just look down in it with a flashlight...youll see it. no real need to cut it open.
A hack saw blade and a cordless drill make sort work of the crimp. I run in a nitro crowd where everyone has to have the latest greatest wiz bang tool…. If I didn’t make everything for the hot rod this po white boy would be a spectator.
Great video! Very informative, hope you can help me. I just got a 2003 FXST and it was running rich. I leaned it out as much as I dare, pilot jet is now at 7/8 open, think I need next size smaller. The issue is the front cylinder plug looks pretty good, but the rear is coated black. I know they are usually not the same, but this is extreme. I would upload pictures but don't see how to. Any thoughts or suggestions, thanks in advance.
One more question. If we pull the plugs and see that our timing is off, to lean/rich, etc. then make an adjustment. put the plugs back in.. how long should it take before we see any changes on the plug? or do we put new plugs in for that instance?
Kevin, really appreciate all the effort you put into your videos. I pulled my plugs the next day to see what they were telling me and none looked right at all so I decided that since they've got 20k on them and they have been in since break-in and two different stage builds that I'd put new ones in and see how they read. Question, how long should I run them to get a good reading? 2017 M8, 22x cam, big sucker and CFR slip-ons. Once again thanks for your great contributions, I've posted several out on some forums to share. Ron
Thank you very much. It can take a few hundred miles to get a really good average. In racing, you can tell after only one run, but you have to have a library of plugs to compare to.
I just found this video after doing some maintenance on my son's '96 Sportster. It had been sitting about five yrs. After all of the initial stuff you do on one that has been sitting I fired it up. I installed the Harley plugs he brought me(6R12), but it was snapping and popping. It cleared up some after a couple rides but still not right. What plug would you recommend for a 883 with a 1200 bore kit. The front cyl. is burning fairly clean, the rear is sooty looking. Thanks
i've never been able to nail down exact range of timing on the plug. i see it as a general check/average for the entire advance curve plus or minus. detail tuning has to be done for specific ranges. great question.
Absolutely the best explanation on spark plugs I've ever seen. Now, which plug or plugs do you recommend on my 2013 Heritage Softail with the 103B? Has the stage one, which entails the performance air filter and two into one Rinehart exhaust, with the Power Vision 2 tuner. Using 91 octane fuel. Thanks in advance.
Hi Kevin, wondering if you can help me. I just pulled my plugs from my 1200 EFI Sportster with bigger cams. The spark plugs only had 200 miles on them. The porcelain is white in colour with no deposits or specs of silver and is not shiny, the centre electrode is nice and sharp. The top two threads have changed colour a little but not sooty. However the only thing ive not seen before is the ground electrode/strap is a powdery white. This simply wipes off with my finger. People seem to say its normal and its usually fuel additives. Ive not put any additives in but always use premium fuel and in the UK its 99 Octane. The bike has been properly tuned also.
Great video! I have a 2018 Heritage 114 with 11,900 or so miles. I’ve checked the plugs every 500 miles and consistently my front two plugs are white. The rear top plug is white, BUT the rear plug pointing to the left of the bike is considerably darker. Normally Harley rear cylinders run hotter than the front so what is happening in my M8 engine? BTW, I’ve had to re-gap my plugs every 2000 miles or so bc the gap widens by 3-4 thousandths during that time.
Wow...you've got some strange stuff going on there. Sounds to me like their may be a ring or valve guide issue on that rear one. Having to regap that often...sounds like combustion temps are getting a bit high and excessively eroding the plug. Check AFR, look for detonation, and do a leak down/ccp test on the engine. Post back comments and let me know what you find. Good luck!
Kevin Baxter Ok! In the past three days I’ve had an Ultra Cool 3.0 heat exchanger oil cooler unit installed. Have spoken with my local HD dealership over the past four months about the white plugs and they didn’t see it as a problem. So, I’ll discuss the matter with the dealership 123 miles away where I bought the bike and add a tuner if the Ultra Cool 3.0 doesn’t rectify what I’ve been seeing on the plugs. Thank you for your suggestions, I WILL DO THEM.
Awesome video, 🙏. I have a 09 road king 96” with a thundermax ECU, SE 255 cam, Vance and Hines slash cut ovals and V & H air cleaner. My plugs are white on one side of the porcelain and grey on the other? Both cylinders are the same. ???
it's really an effect of how the flame front travels thru the combustion chamber. If all the other aspects look correct, I wouldnt be too concerned. People that want every last ounce of perfection, can index the plugs and that can cure/help this but most dont do that these days because any improvement is pretty much impossible to notice.
Wow. New to the channel, but member'd right right up. Very impressed the with level of sophistication and detail. However, didn't check the plugs before I purchased my most recent Harley which I am about to take to the dealership right now for new tires after getting temp plates only within the past hour. My spark plugs are sootted up almost in total. Clearly there's work to do. Where do I start?
Welcome aboard! Thank you sir! I would suggest put some miles on it. Ride conservative. Evaluate your fuel economy. 38 to 42 mpg is a good range. Much less, it may be too rich. Also...smell your oil. If it smells strong of fuel, all of these are examples of an improper tune. Have it at least evaluated. Run too rich for too long, it will reduce engine life. All the best. Be sure to check out all of our members only videos as well.
@@KevinBaxter I did not smell gasoline in the oil, but it's getting tires now, so, I will check it then again. IF it it running rich, whats the remedy, in general?
Hi Kevin. Thank you so much for all your work with these videos. I am wondering, how long would it take to get a proper reading on a new plug? Would a short ride be sufficient?
Thanks for the info, this video is awesome! Quick question,... how would one test cruise half throttle ect ect... if you said it I missed it lol. Thanks ago for the awesome video
Man I wish there was a way I could get you to look at my plugs right now. My front plug looks like the @7:00 and my rear looks like the plug @10:25 with a white color spot close to the threads. 2008 flhtcu. Fuel injected. Any ideas anybody?
what does it mean if one side of the plug ground strap ,porcelain and electrode have white deposits and the other side looks smooth and tanish is it oil migration ? and the rear cyl plug on my 07 96ci is noticeably whiter much hotter?
hey Kevin, I am new to the harley world. I have come to possess a 1987 flhtp, If I need to change the jetting of the carb, what is a good starting increase or decrease depending on the plug read? Thanks for any help you can give. fred
This old dog has learned a new trick! After reading motorcycle plugs for decades, earning respect from my peers. I feel this video has been the most informative piece of proper tuning information I’ve ever been lucky enough to come across. Mr Baxter thank you so much for sharing your knowledge and time with us. I’ve been missing half the story plugs have been telling me.
I just wanted to thank you for the videos you have posted on RUclips. I've been doing this for almost 40 years now and you're the most knowledgeable Harley Davidson mechanic on the Internet. You look at things from a different perspective than the average wrench and it all makes perfect sense. Keep them coming and Thanks for the help.
best spark plug reading tutorial I have seen so far.
Sorry for the poor detail focus on the plugs..camera wasnt working right but I think its enough for you guys to get the right idea.
Macro photography is always difficult. Because the depth of field becomes shallow. This is also true of video cameras and even harder to manage with video.
Sure, blame it on the camera. lol
Excellent tutorial thank you very much. I learned a lot.
I raced motorcycles for 25 years and I just learned things I wish I'd known years ago. What's particularly great about your style is you not only explained it, you connected enough dots that what you showed is logical, and remembering the concepts you can figure out what it should look like. That's great teaching. Thank you, I'm subscribing after one video view.
I can't believe this clip comes up today. The very day my bike tuner who's is doing a build for me was talking about reading plugs & your name came up as you were the first to comment on hos post. Brian from EASTERN BIG TWIN. Australia.
G'day 😉👍
Best plug breakdown I have ever seen.
You saw it did you? Every scene he demonstrates is out of focus. I can't see anything he is talking about.
@@philmcclenaghan7056But his face is perfect focus.
Wholly shit, and I thought I knew my mechanical skills to work on my own Harley, this video just threw all that out the door, what an amazing informative educational video I just watched, out of all the tech videos I have seen, this is by far the best I have seen, thank you Kevin, 👌👍
Thank you John. Have quite a bit on content on here with more coming. Appreciate the sub.
It is a pleasure to hear someone speak. English Thank you Sir for the great knowledge that you shared.
Thanks and welcome
thanks, prolly one of the best spark plug readings tutorial I've seen, i hope i can put it to good use at the track this summer.
Thank you very much sir! I appreciate it. I hope it does.
@@KevinBaxter the only thing you missed was cold rating. Other than guessing, is there a way I can tell if i have the correct plug. If you don't know i run a turbo road king w/98" that runs 30lbs boost (not a typo lol) currently running ngk's dcpr9e
No doubt there sir. As you know, much of that can change a little when dealing with boost, nitrous, alcohol, nitro, etc. I didn't even go there on this one because very very few people take things to that level and I didn't want to confuse anyone. 30lbs boost...just how big are those cyl studs? lol. Anyway, to answer your question...in a boosted engine you can also use the ground strap as an indication of plug "temp". You would want the color change in the exact same area however, if you aren't experiencing detonation and you know the timing is pretty dang close, use that to determine if you could run a hotter, or colder plug. If the color change is close to the tip, run a hotter plug. If it's closer to the threads, run a slightly colder plug. You want in right in the middle of the bend. Also, pay very close attention to the center porcelain. If it starts to look glossy....as if its melting, definitely run a colder plug. Hope that helps.
@@KevinBaxter if you find yourself with some extra time on your hands check out the road king, I have a few video up here on the tube of it. I built it last year from the ground up, started with a bare frame, no parts no motor nothing acquired it all for the build and did it for about 15k total investment, you will see the progression of me turning up the boost, I started out 12lbs then went to 18lbs, then 22 and then just let it eat at 30lbs, i think i can make even more boost yet, it sounds like a 2 stroke chain saw going down the track. I've been doing all the tuning with some help from my local HD'er setting the AFR's and making sure i don't run into spark knock. By the way I swear by Kimbal White studs, wont ever use anything else.
Wow! this knowledge of spark plug wear amazes me!
This Man is a Harley engine Surgeon!
That was the most detailed video explaining reading spark plugs iv ever seen thanks so much for doing that
Glad it helped
Mr. Baxter the information that you give is is so educational on a real level you always keep it straightforward facts factual and I appreciate you giving your time up to help all of us out here become better writers and better tuners God bless you..
Well he picked up another subscriber I've watched couple other videos and doesn't ever suggest taking the bike to the dealer he's a VERY GOOD PERSON to learn from
WOW! I’m going watch again with a note pad. This has been black magic for years to me. Never found a good explanation on the process of tuning from spark plug color. Thanks for the great info!
Thank you sir. Be sure to watch the follow up video where I applied the same principals to the 270 inline 6 in my 1949 GMC. I call it the "Stovebolt" project.
Best video ever made on reading plugs. Thanks so much. I just changed plugs on my 18 gsxr 1000R for the first time 7K miles.
This is the best of all explanation i could find, 10/10 thank you
Mr Baxter, not since I was in Auto Shop have I found some one like yourself that provided a really comprehensive explanation, your an excellent teacher, must be hell of a mechanic. I am now a subscriber to your channel.
@kevinBaxter this is the most advanced explanation I’ve ever been able to find on reading plugs outta Harleys. I learn so much from watching your stuff man. Can you do another video some time reading a larger array of ‘bad’ plugs? I still have so many questions on plug conditions I’ve seen and I know there’s more to learn. Keep it up brother, your channel is the best you are definitely the guy I want to learn more about HD engines from. The attention to detail and breadth of knowledge and experience you have is so hard to come by. And just straight up professionalism and craftsmanship. I love it you’re my kind of people man keep it up !! ✊🏻
excellent Kevin. I sure did not know plug reading to this level. Just the ceramic coloring to tune the carb jets to the new carbs/pipes, etc. Worked just fine for me in the 70's on 2 and 4 stroke bikes.
Thank you sir. Glad it helped.
I built a 1974 year Shovelhead all stock. Later I has a 1980 Shovelhead with a mild cam and S&S B carb. My Toyota tech friend told me to run Toyota plugs. So for all those years I ran the ND-16 U-groove Toyota plug. Also a great plug against seizing in the head. I never had one to foul out and always ran clean. I also ran them in my 1994 Heritage Evo with crane 490 cam and S&S E model carb. Great plug. In my 2010 Heritage, I was going to try them and for some reason, the 2010 Twin cam engine has some off the wall thread diameter that the parts store could not cross reference. I run SE plug in it. Oh Well
Just learned more in 5 minutes then I did in shop class 30 years ago!
Kevin never considered the amount of information a spark plug could reveal. I figured if it wasn't fouled we are good to go. Thanks for the education. Always fascinated with the true inside stories, nice presentation.
Hey there Del! Good to hear from ya bud. Hope you and the girls are doing well.
I have a 1974 shovel with lots of head work including bigger inlet valves, an S+S big bore kit, C grind cam and dynamically ballanced crankshaft and it goes realky good, nearly as fast as my 1999 twin cam. About 20 years ago i gave it a full service ready for an interstate run with my club, then it was hard to start coz i took all the electric start off so kick only and it always started 1st kick hot or cold, but then it would take 20 kicks to start, so i pulled the spark plugs out and cleaned up the old ones and put them back in and it started 1st kick again, so i looked at the numbers on the new plug and they were the same except for a R at the end of the number so i took them back to the store and they told me that the EPA made a rule that all plugs had to have a resistor in them to cut down radio interference so i hunted around and couldnt find any plugs without a resistor in any brand of plug, so now i am using the old plugs and have been using the same plugs for 35 years, and just clean them when i do a service. I found split fire plugs and they worked for a while but they went out of buisness years ago and coz they are split fire it made them hard to clean so back to the old Bosch plugs. I have points in the ignition so i can presume that resistive plugs would work with electronic ignition but my mates with electronic ignition and kick start only all have trouble starting. So my question to you is do you know of any spark plugs that dont have a resistor in them. Appreciate any help you can give me on this subject. Johnny
Great video, i tuned My 2013 Streetglide D&D Fatcat exahaust with the DynoJet Powervision but without O2 Sensors and adjusting all fuel setings manually. I just raised the fuel up a hair and rode a little and kept bringing it up based off how it was running and reading the plugs, I just went on a 3200 mile trip out to Utah, rode in 100 degree heat and 12,000 foot up in Colorado, the bike ran great and when pulling a plug after i got back i expected to see signs of riding in the heat but the plugs looked great based on your video here, just a slight color change 2 threads down, i actually raised the fuel up a tad after all that since they looked more grey where ypur showing more black but the center porcelin is still white. This has been a lot of fun and i no longer hate fuel injection and think this actually works better then a carburator. Your video taught me enough to get it runing perfect. One thing you cant teach though is common sense, you will need that to tune this way. A lot of people are hard headed and refuse to learn, in there case they're better off to just use a pre tuned map or whatever you call that or pay a Tech. I like the hobby aspect of doing it myself.
Awesome job! Good on ya man!!!
How do you adjust the timing with a power vision?
Great to see some old school true mechanical skills , I have not seen or heard of this since I was an apprentice 30 years ago
You and your shop are an amazing resource! Thanks for all that you do!
I appreciate that! Thank you!
I have to say that even though I can read a plug very well, this is the first time I've heard of taking the porcelain out to get an accurate reading of the throttle range.. It's was the only way I had to set up my card at the drag strips... It was not uncommon to go through 6-8 sets of plugs in a day... I will say though that I also have a Wego III exhaust gas analyzer with data recording... Great tool.. Well Done.. Thank you...
That was the best explanation on plugs i have seen, Thanks kevin
Very welcome
Dear Kevin i'm a new subscriber just really diving in to harley engine dynamics. I love what you are doing to educate the average, and experienced cycle enthusiast. My only complaint, and not a huge one, is this video specifically needed to have the focus of the camera dialed in a little better. The closeup was just fuzzy enough to make it hard to see what exactly you were trying to show.
Welcome aboard! THanks for the kind words sir. I agree. That close, the camera auto focus on macro doesnt work very well. i did a follow up here....a little more clear. Thanks for the sub - ruclips.net/video/bIS28KRT4AY/видео.html
Absolutely fantastic ! Thank you..... can't wait to take my plugs out tomorrow and analyze away.
Best of luck!
Kevin, Nice to see a real technician giving advice and explaining what is going on. You certainly separate yourself from 90% of the "so called mechanics"...Im having some problems with my 03 Road King and would love to get your advice on what might be happening...would you be willing to help me and if so can I write to you offline of youtube.???
Best plug video on the net by far
Appreciate that. Thank you for the kind words. Glad its helpful.
I really do enjoy the presentation, and it makes it very simple to RETAIN! Thanks so much!
Glad it was helpful!
Kevin just watched this video again!!! It's worth watching over and over, It's a great reference tool. How's the NEW SHOP going? JV from NJ
I have a 2001 twin cam and after watching this video I thought let’s go see how my plugs look! So the rear plug looked great but the front was all black from carbon power, so what am i having a huge difference in cylinders? Great videos very educational!!
What an absolutely brilliant video thanks so much for sharing Kevin its a constant learning experience in life absolutly terrific video.
Great info. Don't own a Harley yet, but I see one in my near future. Am amazed at all of your content. Have one question if anyone would answer. He lost me when he mentioned the 12.8 to 13.2.
Thank you sir, been waiting for info like this. Re jetting a S&S 96 and always ran rich. Ran good but always black plugs. With gas with higher octane, like 110 I had a chocolate color. Always ran poor in low rpm. Finally re jetted the carb and with 91 octane I'm getting a nice cocoa color and a lot more torque and better throttle response. And always wonder if my timing was correct. After looking at my plugs and still wondering if I'm in the right area, I saw this video. I think I feel better knowing that I'm pretty close and shouldn't have to worry about blowing up an engine. Great content!
Kevin, new subscriber here in Canada. Absolutely fantastic channel with professional on-point info (I’ve watched them all)
and great presentation. I’ve done about 15 twin cam builds and 1 M8 (all in my home garage) and must say that your knowledge and experience is invaluable. My tablet and your guidance will forever live atop my tool box with my shop manuals for easy reference. Keep up the great work Kevin.
Awesome! Thanks and welcome. Glad i can help. All the best to you. Where in Canada?
Kevin Baxter Up in Kingston, Ontario. 25 minutes and directly across from upstate New York border. Ride the New York, Pennsylvania, Virginia, NC/SC states. Haven’t been to GA yet but plan to. Would love to drop in once things open up. Be well, be safe and keep us all fed with your great knowledge.
Thx.
I love Kingston. Know the guys at Motosport Plus...well I did until ownership changed anyway (Tony Hewitt used to work there...good fella). I went up there a few times to train them on EFI tuning. You probably know of Bob McKay...McKays cycle creations. he was a very very dear friend. Wayne at Heritage Cycle Works....great friend as well. I actually have a few boxes of pucks from Canadian Tire bought from the Kingston store. I use them as feet on my equipment. Actually the first time I had a Timmys was with Bob, his wife Dianne, and my wife in Kingston several years ago. Hard to beat a Timmys. I was just up there a few months ago...I drive up and cross over by way of the 1,000 island bridge. Have also judged the Toronto bike show a few times. If you find yourself near Ga...welcome to come by anytime.
Kevin thank you this will help me tune my 110 CVO with my powervision tuner.. now I can dial it in better ...👍
Glad to help
Amazing knowledge for bikers, thanks much. Checking mine today.
Great content!
Question? If the color change is in the curve of the ground strap, that indicates proper ignition timing. But, is this proper ignition timing at cruise RPM where the engine spends a lot of time or does it cover the entire RPM range considering different RPM’s and engine loads require different amounts of ignition timing advance? Thanks
Great info. Thanks. wonder if chalk on the ground strap would help even more to recognice good ignition. Hard to see on my spark plug. When i cut with oxygen and acetylen i use chalk to follow where to cut. And the chalk would not burn of. Maybe that could be a help to see about the ignition. My engine is an 106 TC stroker. with a high correct compresson ratio. About 9.7:1.
So im trying to get air/fuel and ignition as perfect as possible. Im using octan booster. Thus hard to check the ground strap. Dave Mackie heads and TC G 590 camshafts. Pulls very hard. Im living in Sweden. Thanks for your thoroughly teaching. Greetings Peder
Great work. Love your detailed look at the colorization of the plugs.
I learned a lot and hope to apply it to my resent engine mods and dialing in timing and jetting. Thanks you very much h.
5:46 this part of the spark plug you're pointing at: on mine it appears stained on one hemisphere -meaning, on some spark plugs the stain has a crisp border where its coffee hue ends and the normal porcelain color begins, but on others it looks fuzzier like powder fouling.
Any thoughts on what that can mean? Anyways great video, one of the most detailed overviews I've found yet!
Thanks for your time. I appreciate it..
As like everyone else said, I appreciate the time and knowledge you share. Some of the best info on you tube! Thanks again!
Excellent video; and very helpful as I get ready for some tuning. I'd like to start with making sure I have the correct heat range plug for my application, can you offer some advice on how to determine this, or how to contact someone for help?
Start with stock. Its very rare you will need a different heat range.
Amazing stuff !!! I always thought looking at a spark plug was look and see if its dirty and needs a clean. I am AMAZED by this absolute WOW !!!!!
Wow...great video. Excellent explanation. And you're right, reading plugs is a lost art, but they can tell you exactly what's happening in your combustion chamber. Thanks again.
I never heard this depth of explanation. 👍
Best Spark plug reading video I have come across by far, thank you. But how do I tell the difference between a spark plug that is overheating due to lean mixture or a too soft a grade plug without examining the Combustion chamber?
Thank you sir. if lean, you will see the white residue on strap and center porcelain. If heat range you will typically see the porcelain turn glossy...as if it's melting.
@@KevinBaxter Thank you for your reply
Ok, great vid. After putting in new plugs, how long do you run the engine before pulling them out to check the tune? Im talking about a street bike running normal fuel under normal conditions. I'm also referring to the fuel mixture, not the igntion timing as I know the ignition timing mark will appear straight away.
A hack saw blade and a cordless drill makes short work of the spark plug crimp. And if anyone knows the part number for a ngk dcpre 7 plug without a screw on top I would appreciate it. The only advantage I’ve come to with HD is being able to run the fine line of detonation due to a roller bearing crank. Swain tech coating stops the pistons from being wear items in high compression pump gas hot rod bikes. Fine video sir, you give insight to why we make the big bucks🙁.
Wow, ill never look at a sparkplug the same ever again, great tips
thank you
Kevin Baxter 👍🏻
Awesome video as usual.... Is there a service that one can send your plugs to get a reading of what's going on? Maybe spot some red flags early? I have a 2010 heritage classic. Stage 1 with a Thundermax tuner and D&D exhaust. I started with the tuner cause I knew I'd need it anyway when I finally got to the exhaust. Bought the tuner thru Cycle Solutions. They sent me the initial base map and then a new map once I added the exhaust. I pulled my plugs after watching your video and they looked nothing like those in your video. No black at all, crusty light deposits all over the ground strap, the outside of the center electrode and even thicker on the porcelain...... So, to put it mildly, I'm concerned. The bike runs like a bat out of hell.... so no complaints from that aspect.... But if I've learned one thing from you; An engine can be self destructing slowly with not symptoms until it's too late..... Don't want to end up there......... Any suggestions where I might turn to for help reading my plugs.
WOW….great information, I wish I would have learned this 30 years ago!!!
Great content and aligns with my learnings from drag racing! 🎯💯
I just recently changed spark plugs, I believe that the ones that I took out were original because they said Harley-Davidson on them and the bike has about 24,000 miles on a stock '05 Dyna Wide Glide fuel injected Twin Cam 88. I wished I would have kept the old plugs so that I could have tried to read the other aspects of it but I threw them away. The plug from the front cylinder had a lot of carbon build-up on the electrodes, so much that the gap was almost completely closed but it wasn't shiny or wet. The rear plug had quite a lot of carbon build-up also but not as much as the the front. The engine had been missing mostly at cruise speeds and also popping from time to time on deceleration. I replaced them with NGK Iridium IX DCPR7EIX spark plugs and it runs great. I also changed plug wires but went back to the originals for now because the new ones were a kit that I put together and they were causing the check engine light to come on. I think I may have damaged one when I was trying to pull the spliced end off of one, I'd forgotten to cut it to length first and twisted it a few times, probably damaged the core wire.
Anyway, I'm curious if that much carbon build-up is normal after 24,000 miles or if something is off.
That's not normal at all. Could be excessive rich mix or oil blowby. Id be doing a leak down and cyl pressure test on that one. Also...valve stem seals were a common issue in that era.
@@KevinBaxter OK, I will look into those things, thanks a lot Kevin.
youre welcome
Thanks Kevin that’s a good video I’m always trying to get that perfect plug
Thank you Ron.
This was an awesome video! I have a dyno at my house and I've tuned a lot of high horsepower nitrous bikes (Hayabusa zx14 gsxr1000 ECT) but I've mainly used the grounding strap just for finding out what timing a nitrous motor likes. I'm going to buy something to where I can cut plugs open and I'd love to compare this method with the wideband on the dyno. By having a cheat sheet (AFR wideband) I should be able to see how close my initial guesses are when reading a plug. Can't wait to try this out with one of my personal bikes
ive done it long enough, i can almost tell you to .2-3 afr what it is by reading the plugs. you will start to see the pattern. just look down in it with a flashlight...youll see it. no real need to cut it open.
A hack saw blade and a cordless drill make sort work of the crimp. I run in a nitro crowd where everyone has to have the latest greatest wiz bang tool…. If I didn’t make everything for the hot rod this po white boy would be a spectator.
@@KevinBaxter love your videos, what’s your thoughts on the E3 plugs? I have a 2011 Fatboy
Great video! Very informative, hope you can help me. I just got a 2003 FXST and it was running rich. I leaned it out as much as I dare, pilot jet is now at 7/8 open, think I need next size smaller. The issue is the front cylinder plug looks pretty good, but the rear is coated black. I know they are usually not the same, but this is extreme. I would upload pictures but don't see how to. Any thoughts or suggestions, thanks in advance.
do a leak down and cyl pressure test. the black you see may be oil not fuel. best of luck!
Great video!! And best of luck in the New Year with all your projects!
Please elaborate on the use of anti-seize on plugs. Thanks
Love it.
You guys Gota be bout the best if not very top of the cream pile.
thank you sir. i appreciate that.
One more question. If we pull the plugs and see that our timing is off, to lean/rich, etc. then make an adjustment. put the plugs back in.. how long should it take before we see any changes on the plug? or do we put new plugs in for that instance?
good question. the changes start to happen pretty quick but...a plug wont really clean itself exceptionally well if it's starting out bad.
Always top tech dive in the deep end.
Big big fan 😉
Cheers this is definitely going to help my ignition setup on my twin cam via the pcv and of course the daytona twin tec setup i have.
Simply the best
Good job Kevin easy to understand good job
Kevin, really appreciate all the effort you put into your videos. I pulled my plugs the next day to see what they were telling me and none looked right at all so I decided that since they've got 20k on them and they have been in since break-in and two different stage builds that I'd put new ones in and see how they read. Question, how long should I run them to get a good reading? 2017 M8, 22x cam, big sucker and CFR slip-ons. Once again thanks for your great contributions, I've posted several out on some forums to share. Ron
Thank you very much. It can take a few hundred miles to get a really good average. In racing, you can tell after only one run, but you have to have a library of plugs to compare to.
Great tutorial.
I watch every video I can.
Thanks ! A lot of great information really helps me know mor about my eco. Thanks
I just found this video after doing some maintenance on my son's '96 Sportster. It had been sitting about five yrs. After all of the initial stuff you do on one that has been sitting I fired it up. I installed the Harley plugs he brought me(6R12), but it was snapping and popping. It cleared up some after a couple rides but still not right. What plug would you recommend for a 883 with a 1200 bore kit. The front cyl. is burning fairly clean, the rear is sooty looking. Thanks
Great Video! when you talk about ignition timing on the strap is this general or can you tell if it's not correct at light load vs WOT?
i've never been able to nail down exact range of timing on the plug. i see it as a general check/average for the entire advance curve plus or minus. detail tuning has to be done for specific ranges. great question.
Absolutely the best explanation on spark plugs I've ever seen.
Now, which plug or plugs do you recommend on my 2013 Heritage Softail with the 103B?
Has the stage one, which entails the performance air filter and two into one Rinehart exhaust, with the Power Vision 2 tuner.
Using 91 octane fuel.
Thanks in advance.
thank you sir. regular old 6R12 or equivalent in other brands. Stock works great.
Is this specific to Harley’s or valid for all bikes? Is this specific to FI or carburetors or valid for both?
A lot to remember, but very informative. Good video.
Hi✌️ for normal street harleys, how much you need to ride to get a good sparkplug read? Thanks!
Great ill have ever had is old champion charts from early sites and 70 ngk for metric bikes
Hi Kevin, wondering if you can help me. I just pulled my plugs from my 1200 EFI Sportster with bigger cams. The spark plugs only had 200 miles on them. The porcelain is white in colour with no deposits or specs of silver and is not shiny, the centre electrode is nice and sharp. The top two threads have changed colour a little but not sooty. However the only thing ive not seen before is the ground electrode/strap is a powdery white. This simply wipes off with my finger. People seem to say its normal and its usually fuel additives. Ive not put any additives in but always use premium fuel and in the UK its 99 Octane. The bike has been properly tuned also.
Great video! I have a 2018 Heritage 114 with 11,900 or so miles. I’ve checked the plugs every 500 miles and consistently my front two plugs are white. The rear top plug is white, BUT the rear plug pointing to the left of the bike is considerably darker. Normally Harley rear cylinders run hotter than the front so what is happening in my M8 engine? BTW, I’ve had to re-gap my plugs every 2000 miles or so bc the gap widens by 3-4 thousandths during that time.
Wow...you've got some strange stuff going on there. Sounds to me like their may be a ring or valve guide issue on that rear one. Having to regap that often...sounds like combustion temps are getting a bit high and excessively eroding the plug. Check AFR, look for detonation, and do a leak down/ccp test on the engine. Post back comments and let me know what you find. Good luck!
Kevin Baxter Ok! In the past three days I’ve had an Ultra Cool 3.0 heat exchanger oil cooler unit installed. Have spoken with my local HD dealership over the past four months about the white plugs and they didn’t see it as a problem. So, I’ll discuss the matter with the dealership 123 miles away where I bought the bike and add a tuner if the Ultra Cool 3.0 doesn’t rectify what I’ve been seeing on the plugs. Thank you for your suggestions, I WILL DO THEM.
Awesome video, 🙏. I have a 09 road king 96” with a thundermax ECU, SE 255 cam, Vance and Hines slash cut ovals and V & H air cleaner. My plugs are white on one side of the porcelain and grey on the other? Both cylinders are the same. ???
it's really an effect of how the flame front travels thru the combustion chamber. If all the other aspects look correct, I wouldnt be too concerned. People that want every last ounce of perfection, can index the plugs and that can cure/help this but most dont do that these days because any improvement is pretty much impossible to notice.
Kevin Baxter Thanks Kevin
Wow. New to the channel, but member'd right right up. Very impressed the with level of sophistication and detail. However, didn't check the plugs before I purchased my most recent Harley which I am about to take to the dealership right now for new tires after getting temp plates only within the past hour.
My spark plugs are sootted up almost in total. Clearly there's work to do. Where do I start?
Welcome aboard! Thank you sir! I would suggest put some miles on it. Ride conservative. Evaluate your fuel economy. 38 to 42 mpg is a good range. Much less, it may be too rich. Also...smell your oil. If it smells strong of fuel, all of these are examples of an improper tune. Have it at least evaluated. Run too rich for too long, it will reduce engine life. All the best. Be sure to check out all of our members only videos as well.
@@KevinBaxter I did not smell gasoline in the oil, but it's getting tires now, so, I will check it then again. IF it it running rich, whats the remedy, in general?
Hi Kevin. Thank you so much for all your work with these videos. I am wondering, how long would it take to get a proper reading on a new plug? Would a short ride be sufficient?
Yes however, it requires much closer examination. Most of the time, to make things obvious, a few hundred miles. Youre welcome. thanks for following.
Wow - that was amazing! Thanks, Kevin!
Thanks for the info, this video is awesome! Quick question,... how would one test cruise half throttle ect ect... if you said it I missed it lol. Thanks ago for the awesome video
I don’t remember you covering it in the video, but how long should you run/ride your bike to get an accurate read on your plugs?
Also the white deposits can be coolant like in a car
Great tutorial Kevin.
Thank you kindly
Can you do such an analysis for 2-stroke plugs? I assume its little different. Thanks.
That's a get Down Kevin , thanx for all that info !! 👊
I'm wondering if it would be wise to have 1 set of plugs for touring, & a different set for around town. Different heat ranges, different gap, etc.
How many miles should be on the Spark Plugs to get a good reading? Love the Video. Thank you
I found the answer by reading your replies. Thank you !
Thank you sir , great video i b using it as a refrence guide for yrs
Man I wish there was a way I could get you to look at my plugs right now. My front plug looks like the @7:00 and my rear looks like the plug @10:25 with a white color spot close to the threads.
2008 flhtcu. Fuel injected. Any ideas anybody?
what does it mean if one side of the plug ground strap ,porcelain and electrode have white deposits and the other side looks smooth and tanish is it oil migration ? and the rear cyl plug on my 07 96ci is noticeably whiter much hotter?
How would I use the spark plug to tune mid or cruise? It was my impression that this is for WOT
hey Kevin, I am new to the harley world. I have come to possess a 1987 flhtp, If I need to change the jetting of the carb, what is a good starting increase or decrease depending on the plug read? Thanks for any help you can give. fred
Thank you mate for making this video.