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Discussion Starter #1
I changed the air filter on the gl1800 and decided to help out a friend in changing the filter, fluids, bleeding ,plugs, anti freeze etc. Applying some Automotive logic, automotive dealers always try and upgrade any routine service to include cleaning the air venturi or throttle body assy. It is felt that dirt and fuel residue that might stop the butterfly plates from closing properly or sealing somewhat against the bores can create a lumpy idle affecting air fuel ratio during idle.

In my friends bike, he had a lumpy idle, after cleaning and gapping the plugs (we did not remember to get new ones) that helped somewhat . This bike has 55,000 miles and has been well maintained. That improved it a bit, but then I took 6 inch wood cotton swabs like used in a doctors office, grouped 5 or 6 together and wet them with carb cleaner from an aerosol can, held open the intake butterflies in the venturi with the throttle and cleaned around the bore. What looked somewhat black, cleaned up perfectly after 3 or 4 changes of wet swabs and seemed to seal much better. The idle improved when started and it sounded much better. This bike had no issues to start with other than an annoying uneven idle.

This might be a good idea for other users to try, it is inexpensive and a productive maint item. I felt I did not want to spray this directly into the venturi from the can, since unlike a car which has the throttle body on a horizontal plane, this one is a direct down shot into the valve area and might dilute the oil or flood a cylinder. When done, I did spray a quick shot against the butterfly pivots to clean them, but only a short burst.

Hope this might help some others out.
 

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I use a half can of SeaFoam in the spring and the other half in the fall.
Seems to keep it clean.
 

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If you read the Service Manual it will tell you to not do what you did. The black stuff that was cleaned off is suppose to be there. There is like carefully place "silicone bead" above the throttle body the helps seal it. GumOut in a spray can will remove it. Its best to follow the procedure in the Service Manual which tells where and where not to spray.
 

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No spraying down there was done. Swabs were used to clean up the buildup. Besides... it cleared up the lumpy idol!

Great tip!:thumbup:
 

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I knew a guy named 'Lumpy Rutherford' once but never heard of this 'Lumpy Idle' fellow.:roll::cool:
 

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Discussion Starter #8
Update

The spray did not touch or go near the silicone bore coves on top of the venturi's visable inside the air filter housing. The black inside the bore is gunk from the air/fuel that percolates after shut down in my opinion. I know the residue is there and I have seen the bores after the car dealers clean them off of the car and they sparkle. Do not do it if you have any fears this is incorrect, I will do mine next week when I change the filter.
Thanks for your comments.
Bob
 

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Make sure your "cleaner" is sensor safe.
 

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Discussion Starter #10
sensor safe

The sensor is on the top cover of the air box, which is removed to gain access to the air filter chamber and and is removed during the cleaning of the bore of the throttle body where the butterfly is located. Using cotton "q tip" swabs with wooden shafts that are 6 inches long give you control to keep the liquid only on the swabs. The sensor is not affected by this, and the results are dramatic. It will take 5-8 cleaning cycles with cotton swabs to get all of the gunk off.
 

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I also tought of Lumpy Rutherford, Wally Cleaver's chum.

I think Goldwing Greg pointed-out an important "no - no!" What you cleaned out may well have been old carbon crud, but there is also a black carbon oxide coating that is applied during manufacture that should not be disturbed. It is always best to have a sevice manual at hand to reference it. I'm glad your erratic idle is remedied.

prs
 

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Pigeon, is this what you are talking about?

Do not apply commercially available carburetor cleaners to the inside of the throttle bore, which is coated with molybdenum.

Is the entire bore coated with this or just a certain part of it? The pictures in the service manual make it look like there's no coating at all.
 

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I recall reading the warning in the manual while doing a service check and air filter replacement the first time. I don't remember how the air intake throat and butterfly appeared, but I do recall that I resisted temptation to clean or wipe it due to the warning. Moly, huh; I forgot that part, thought it was some sort of carbon compound. Thank you for the refresher!

prs
 

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Discussion Starter #14
Coating in bore

You guys are right, I looked up the info in the service manual and it was a little hard to find, on the first page in text only. I cannot understand why they would put a layer of grease in the throttle bore unless the butterfly has a tendency to stick in the bore. The surround of grease was about 1/2" tall and covered the area where the butterflies touch the bore. I had never seen that done before, I guess automobile wisdom did not apply here. Thanks for the heads up.
 

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Glad to hear you didn't spray anything in there! That method has pretty much gone the way of the carb...

Most modern throttle bodies have some kind of coating on them, and can be damaged by spraying carb cleaner, Hogwash, or other induction cleaners in them. Cleaners can also sometimes get into the IAC valve, and mess those up as well (not sure if the Wing has one, I assume it does).

"Sensor-safe" is just not for MAP and other 'topside' sensors, but really applied to the O2 sensor. The burnt or unburnt cleaner can foul an O2 sensor.

The bike doesn't happen to have a K&N filter on it does it? Many people over oil them and it will gum up a lot of stuff downstream...
 

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Discussion Starter #16
K&N Filter

Didn't stop and think about the O2 sensors, We did not spray into the barrels of the venturi, just swabbed with long wooden Q tips. The coating is just a swab of grease around the inside of the barrel where the butterflies make contact with the walls.

My friend HAS a K&N, we oiled it lightly and when it did not come up "pink" enough we oiled lightly again. It was NOT sopping or anything like that. Personally I don't get the K&N thing I personally believe the original filter passes enough air freely and O2 sensors adjust mixture to that airflow. These may have helped in Carb days but I'm not too sure now.
Thanks for the reply.
 

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I have a new throttle body to install and since there were questions about whether a lubricant was added and where it was I thought I would take a picture and post it here. It's only on one side of each intake - both top and bottom. I don't know what it is but I hope this answers some questions.

 

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Discussion Starter #19
Lube in Throttle Body

Thanks for the info, Can't imagine what the lube is there for, but it is. I could not see it that good when it was mounted up. Why did you need to replace it, isn't that a low wear item?
Bob
 
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