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Just a quick question regarding my plugs. Running HD 5r6app double platinum. The rear cylinder plug has a dark mark on it and im not sure what it means? I noticed this a couple weeks ago and switch the plugs from front to back so I know its not the plug(s). Heres a pic of both plugs and you can see the dark mark im talking about.
My rear cylinder shows a little more color than my front. Especially when I use my enrichener (choke). The front one looks pretty good. The rear ain't bad either. How many miles on the plug?
Check out those links. I think your plugs aren't bad based on what I can see. YD
Last edited by Yankee Dog; Jul 8, 2015 at 09:12 PM.
I thought I read on the forums that todays Ethanol fuel will not generate a tan color. Any truth to this? I wonder, as I usually try and tune for the nice tan color. My bikes are Carb'd bikes.
I use the choke every time I start the bike for the first time cold, after that for rest of day it's not needed.
I ride at least 3-4 days a week and it's HOT were I live, been 105-117 deg last few weeks. And I ride a lot at elevations over 4000'. I bought some NGK plugs last night that are a couple steps cooler to try out but didn't ride today.
I thought I read on the forums that todays Ethanol fuel will not generate a tan color. Any truth to this? I wonder, as I usually try and tune for the nice tan color. My bikes are Carb'd bikes.
My bike is carb'd also. I live in Cali so highest i can run 91 octane.
Your front looks great, and like 97 dyna mentions, a little soot on the rear. But mine does that when using the enrichner.
Otherwise, my plugs stay pretty much "new" clean except for the lines mentioned in those links on the strap (timing) and deep where the ceramic meets the body of the plug. My porcelian stays white with a hint or shadow of color .
I keep thinking it is lean, but I get no ping, no spots, no signs of excess heat, and my ignition timing is dead on, so I leave well enough alone. I had more color to plugs until I re-routed the breather hose (head breather) to the carb. It now just vents to the outside air and I have since lost most of the color on my plugs.
I watch for signs of overheating, and I don't get them. So I am leaving well enough alone. YD
Your front looks great, and like 97 dyna mentions, a little soot on the rear. But mine does that when using the enrichner.
Otherwise, my plugs stay pretty much "new" clean except for the lines mentioned in those links on the strap (timing) and deep where the ceramic meets the body of the plug. My porcelian stays white with a hint or shadow of color .
I keep thinking it is lean, but I get no ping, no spots, no signs of excess heat, and my ignition timing is dead on, so I leave well enough alone. I had more color to plugs until I re-routed the breather hose (head breather) to the carb. It now just vents to the outside air and I have since lost most of the color on my plugs.
I watch for signs of overheating, and I don't get them. So I am leaving well enough alone. YD
Thanks for the explanation and again for the links. Analyzing my plugs with the links I can see my timing looks good, the color starts changing right near the middle of the 90 deg bend. I have 2-3 threads that are duller/darker color and the porcelain area looks ok, a little rich. Going to a cooler plug didnt make much of a difference and reading the links above actually my plugs if anything look like one range hotter actually might be needed. But its running great as it is so i'll do the same as you and put the HD Platinum's back in and call it good. Just trying to take care of my bike and keep up on whats going on inside of it best I can. Thanks again for the help.
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Quick spark plug ? with pics
