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Discussion Starter · #1 ·
With respect to my earlier topic "Need Help Diagnosing a Motor Problem" I have a question regarding carbon build up. First off, for those of you who provided me with information on the above mentioned topic, thank you. My question has to do with removing carbon build-up on the heads and pistons. Is there a safe way to remove this build-up without taking off the heads? Is there a product (or process) out there that I can use to do this? The motor has at the most 3 hours or 100 miles on it, so the carbon shouldn't be too thick, at least I hope.

Thanks for your help.
 

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Highly Seasoned Rider!
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zoomingm3 said:
With respect to my earlier topic "Need Help Diagnosing a Motor Problem" I have a question regarding carbon build up. First off, for those of you who provided me with information on the above mentioned topic, thank you. My question has to do with removing carbon build-up on the heads and pistons. Is there a safe way to remove this build-up without taking off the heads? Is there a product (or process) out there that I can use to do this? The motor has at the most 3 hours or 100 miles on it, so the carbon shouldn't be too thick, at least I hope.

Thanks for your help.
You won't have much carbon buildup in your engine with only 3 hours on it. WIth modern unleaded fuel, I've not noticed much in the way of carbon buildup in my Shovelhead.

One way to keep the carbon down is to take a good blast down the road now and then.
 

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Shithead
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I agree with that. With 3 hours and modern fuels you won't have any carbon in there that will survive a half decent ride, even if you were running a bit rich.

What you see on the plugs won't be there on the piston tops.

De-coking engines is pretty much a thing of the past, even on shovels.
 

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Discussion Starter · #5 ·
Thanks for the feedback guys.

As far as not having alot of carbon build-up after 3 hours, that's good news but, when I shine a light down into the cylinders I can definately see black carbon or something black on top of the pistons. In fact, when I'm looking at the top of the piston I see the area where spark is closest to the piston, it's much lighter in color. What could be causing this condition? Is it due to a rich condition or could it be a timing/ignition issue?
 

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Shithead
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The burn in the combustion chamber starts from where the plug is. So that area gets hotter and is more carbon free. As the burn moves across the rest of the combustion chamber, it gets cooler, so more carbon gets left.

Just get her up to temp and give her a good run. You'll be fine.

There will always be some variation in burn conditions in different parts of the chamber.

Twist the wick, man :D The old girl won't let you down.
 

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If the black soot is shiny it could be overheating... check the timing and timing advance. If the soot is dull olored and soft it is running rich possibly from to little exhaust back pressure.
 

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For some reason I get the impression that you probably have the cleanest bike in the county....

Don't worry about carbon. It's a natural condition. It gets scraped during teardown. Techs are advised not to scrape the carbon buildup off of the top rim of the cylinder unless the cylinder is going to be bored and new rings are going to be installed. The carbon buildup there helps seal the combustion chamber when an engine gets worn.

Just read your spark plugs. If they look good, you're in business!

JD in CA
 
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