Plugs from my 2007 1200N after about 1k miles. Mods are Screaming Eagle Heavy Breather, Vance & Hines Big Radius 2-2's, and a PC3.

Thanks for any input!

 

I think they are a bit lean..........
Here's a chart to compare them to.

http://www.dansmc.com/spark_plugs/sp...s_catalog.html


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That's an awesome link! Thanks for posting that

 

I am not the Author
But This Is very accurate :::

I have been posting this whenever someone needed help tuning, and it was just suggested that I start a thread with this so that I won't have to repost every time someone needs it.
This method comes from my long term friendship with Brad Urban who until he passed away a few years ago was one of the leading carb builders in the world (The Carburetor Shop), and for a period of about 6 years I went with Brad to one of the different short tracks in Southern California every weekend durring racing season to tune his carbs. For that 6 years his carbs were on cars that heald the track record at every track in Southern California for the entire period, and three of four cars in the trophy dashes were routinely his too. This 6 year time period started while Ascot was still running and continued past the time that Ascot was closed down. Brad was featured in Hot Rod, Super Chevy, and Circle Track regularly, and the world of racing lost a lot with his passing. It is my aim to keep his method alive, because I am not getting any younger myself.

Plug Reading 101
First off, forget everything you think you know from reading repair manuals because that only works on engines with old used plugs and engine problems that are easy for the average person to see on the plug without any special training.
Plugs can be read with as little as two laps on them at the track.
· Start with new, or extremely clean recently new plugs.
· Best readings are taken by running the vehicle at sustained speeds in the range that you are checking, IE: “Wide Open”, Mid Range”, “At or near Idle”, then disengaging the clutch, killing the engine cleanly, and coasting to a stop.
· Overall readings can still be taken without a clean kill and stop, even without new plugs. This is still very accurate, and one of the best tune up tools you have. Just make sure that you have good plugs and by keeping an eye on them as you make changes you can read the effect that the changes made. This just requires a mental track record or a written one.
Where to read them.
· The porcelain is used for reading plug heat range, and timing only. Never try to read fuel mixture off the porcelain.
· The inner wall of the metal shell extending down to where that meets the porcelain is where you read the mixture.
· Engine problems such as oil consumption, etc., are read by going back to your manual. We are only concerned with a good sound engine for fine tuning purposes.
How to read them.
· Timing that has too much advance will show as black flecks on the porcelain. These are flecks of aluminum off the piston due to detonation. Even a good running engine will show signs of minor detonation, but keep an eye on those flecks and if they get bigger and more of them it’s time to look seriously at the timing.
· To determine heat range of your plugs look at the porcelain as it starts to take color. If the porcelain is white to a light tan, the heat range of the plug is right. Remember we are talking a couple of laps so it doesn’t have much time to take color which is why white is acceptable. If it starts looking gray or black possibly even a bit wet looking, the plug is too cold. The more black it is and the more it is wet, the further to the cold side it is. If the plug is dark tan or worse yet getting a burnt black look to it with blisters on the porcelain, then it is too hot a plug. Note the difference between a cold black and a burnt black at the two extremes. They are not the same black by any means. Fuel deposits on older plugs flake off, so don’t confuse that with blistering.
· For reading mixture, read the metal inner wall ONLY.
· The upper ring around the electrode area (as you hold the plug electrode up facing you) is where you read the idle mixture. Correct reading is MEDIUM GRAY. Light gray to whitish gray is lean, dark gray to black is rich, with powdery black being richer yet, then after that it starts to get wet and the black gets flushed off like it was rinsed with gas. (You will see some of this on the intake valve side of the plug and that is not a concern if the color is correct otherwise).
· The lower ring where it meets the porcelain way down inside (you need a magnifying glass and good lighting to see clearly down to the bottom), is where you read wide open throttle. Color readings are the same for all ranges except that the wet flushed off look is only going to be showing at the idle portion of the plug.
· The mid range is everywhere in between that top ring and the bottom ring. Color is again read the same.
To bring this into perspective for the Sportster.
· Stock timing will be acceptable unless it’s broken. I see some specs on mine, so some over advance seems normal, just keep an eye on it over time looking for changes.
· Stock heat range of plug will be good through stage 1 and possibly stage 2. If the compression gets raised too much then you may need to drop to a colder plug, and that will become evident if the porcelain gets dark tan to black and blistered.
· Idle reading will be a function of the mixture screw, and the pilot jet. If that upper ring is light tan or whitish, then open up that idle screw until the engine sounds right (about three turns to three and a quarter out for stage 1). Only consider upping the pilot jet if you can not get it right with the mixture screw.
· Mid range will be a function of the needle, the needle position, and close to idle the pilot jet will effect it too. The Main jet will also effect the mid range, but at the same time it will effect the wide open throttle setting too.
· Wide Open Throttle is mostly the Main jet.
I always work on idle and WOT first. Once I get those in range I take it for a good ride and pull the plugs to double check those two extremes and start working on the mid range which takes more patience.
To fine tune it in any range, do the clean kill in the range in question, then read that section of the plug.
As long as the plugs are reading nice in all the ranges then you can periodically look at them and see that everything is still good. I always take compression and read the plugs every time I do a tune up and I change the plugs out for every tune up too (5000 miles)
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Here Endeth The Lesson XD

 

Thanks for this good stuff Os, I just took these plugs out of my 2007 1200C, they have 14,700 miles on them with about 13,000 equipped with a PCIII. I think they look good, close to picture # 14 in the comparo.

 

Yep I think so,,
All I look for on mine Issa copper/coffie color,,like coffie and cream tan..
Mine where chalky white before my X14ieD's,,,
they good to go now XD

IMO The chalky white Is bad news,,
Too rich colors just mean a crappy running engine..