Best plug breakdown I have ever seen.

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.

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.

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.

This is the best of all explanation i could find, 10/10 thank you

It is a pleasure to hear someone speak. English Thank you Sir for the great knowledge that you shared.

Super informative and by far the best spark plug analysis video i've seen yet. Thanks Kevin

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, 👌👍

best spark plug reading tutorial I have seen so far.

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

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

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..

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.

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 !!!!!

As like everyone else said, I appreciate the time and knowledge you share. Some of the best info on you tube! Thanks again!

That was the best explanation on plugs i have seen, Thanks kevin

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.

You and your shop are an amazing resource! Thanks for all that you do!

I really do enjoy the presentation, and it makes it very simple to RETAIN! Thanks so much!

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.

Wow! this knowledge of spark plug wear amazes me! This Man is a Harley engine Surgeon!

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.

That was the most detailed video explaining reading spark plugs iv ever seen thanks so much for doing that

Thanks ! A lot of great information really helps me know mor about my eco. Thanks

What an absolutely brilliant video thanks so much for sharing Kevin its a constant learning experience in life absolutly terrific video.

Great tutorial. I watch every video I can.

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 😉👍

Thanks for your time. I appreciate it..

Just learned more in 5 minutes then I did in shop class 30 years ago!

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

Absolutely fantastic ! Thank you..... can't wait to take my plugs out tomorrow and analyze away.

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...

Best plug video on the net by far

WOW….great information, I wish I would have learned this 30 years ago!!!

@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 !! ✊🏻

Great content and aligns with my learnings from drag racing! 🎯💯

I never heard this depth of explanation. 👍

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!

Thank you sir , great video i b using it as a refrence guide for yrs

Thanks Kevin that’s a good video I’m always trying to get that perfect plug

Great video!! And best of luck in the New Year with all your projects!

Kevin thank you this will help me tune my 110 CVO with my powervision tuner.. now I can dial it in better ...👍

Good job Kevin easy to understand good job

Wow - that was amazing! Thanks, Kevin!

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, 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.???

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.

A lot to remember, but very informative. Good video.

Always top tech dive in the deep end. Big big fan 😉

Good video with a lot of information, much appreciated.

Kevin is the GOAT

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

Nice detailed run thru on reading plugs...Cheers!

That's a get Down Kevin , thanx for all that info !! 👊

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

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!

Great ill have ever had is old champion charts from early sites and 70 ngk for metric bikes

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!!

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

Thanks for the upload great detail video

Love it. You guys Gota be bout the best if not very top of the cream pile.

Great tutorial Kevin.

Professor Kevin ya definitely schooled me with this one 👍👍

Learned something new today👍

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 mate for making this video.

This is so useful! Thank you!

Excellent! Thanks man!

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.

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 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 channel bro - well appreciated

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.

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.

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 video sir

Very interesting, thank you.

Excellent

Wow, ill never look at a sparkplug the same ever again, great tips

Thank You Kevin! 👍👍

Hi✌️ for normal street harleys, how much you need to ride to get a good sparkplug read? Thanks!

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🙁.

What about the front plug runs leaner than rear cylinder on 1200 sportster? Should you run rich for rear and the front on the money or run front leaner

TY Kevin!! Great Video...

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.

thanks, that's helpful!

Can you do such an analysis for 2-stroke plugs? I assume its little different. Thanks.

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

Great info! Thank you! 👍

Please elaborate on the use of anti-seize on plugs. Thanks

Spot on...thank you.

Kevin, what kind of spark plug would you recommend running on a stage 1 twin cam? Copper or iridium?

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

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.

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.

Aftermarket spark plugs and wires does it affect ECM for tuning?

Máster class!! Just great.

my hat is off to you sir.

Thanks sir