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OK, now that the charging system seems to be understood by me it's time to move on to the carb's.

I have a slight hesitation and sag in the power band from about 2800-3200 rpm's. Other than that it runs great.


The pilot jet adjustment screws control fuel flow but even opening them up some more didn't cure the sag? A have shimmed the 4 jet needles up some & that seems to have helped the sag a good deal.

Right now I have them (pilot needles) set at 2-1/4 turns out from seated. All 4 do effect the idle speed so I know they are working. It idles great at 1050 rpm & anything over 3600 rpms it pulls great.

Twisty
 

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The pilot screw controls air. Did you try balancing the carbs? Goldwing carbs all seem to need balancing every 5000 miles.
 

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BRowan wrote:
The pilot screw controls air. Did you try balancing the carbs? Goldwing carbs all seem to need balancing every 5000 miles.
Brian,

do the pilot screws control air at all rpms or just at idle?

dean_3326 :12red:
 

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BRowan wrote:
The pilot screw controls air. Did you try balancing the carbs? Goldwing carbs all seem to need balancing every 5000 miles.

BRowan, no, I haven't balanced the carbs yet. I am trying to get the pilot jets set for best runability first. The engine pulls great and even at both idle and mid throttle up so I don't believe they are too far out of balance.

Now on the pilot screws controlling air? Those screws are to be turned in more for high altitude operation according to my service manual and we all know you must lean out for high altitude use so something doesn't work out correctly here. If those screws controlled air you would think they would have to be opened more for a leaner mixture ataltitude. I'm really getting confused now.

I really don't know the answer myself, that is why I asked the question here. Where did you get your information from?

Twisty
 

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Twisty, the pilots control air. Opening them up allows more air, more air = weaker mixture. So your manual is right, turning the screw in richens the mixture. Isn't it a richer mixture you need at altitude?
 

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It's been a long time since I jacked with the pilot adjustments on my 1100 but I seem to remember Honda calling for them to be seated, then screwed out about 2 turns then adjusted out further at idle until the RPMS dropped then back in a half turn from there. You have to be patient because it takes a little while at idle for the adjustment to be seen by the system.
 

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GWEddie wrote:
Twisty, the pilots control air. Opening them up allows more air, more air = weaker mixture. So your manual is right, turning the screw in richens the mixture. Isn't it a richer mixture you need at altitude?

GWEddie, yes, I am looking for a richer mixture but am very confused about those being air screws.

My service manual says to TURN THEM CLOCKWISE to a 'less turns out' setting for high altitude usage. Asa general rule you need to lean out a carb for high altitude operation.

I do know on some carbs those are air screws and on others 'like Harley's' Kehins they are fuel adjusters.

It just seems odd that Honda would suggest turning those screws in for high altitude usage if in is richer?

There is less oxygen and less atmospheric pressure at high altitude so the fuel setting usually needs to be leaned out for high altitude operation.

Someone please straighten me out, what am I NOT understanding here.

Twisty
 

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hitechluddite wrote:
It's been a long time since I jacked with the pilot adjustments on my 1100 but I seem to remember Honda calling for them to be seated, then screwed out about 2 turns then adjusted out further at idle until the RPMS dropped then back in a half turn from there. You have to be patient because it takes a little while at idle for the adjustment to be seen by the system.

hitechluddite, I did do the service book pilot jet screw adjustment and it was very close to what you suggested 'a couple of extra steps but close to what you wrote'.

Problem is I still have that lean condition just off idle to about 3000 rpm.

I want to richen the mixture slightly above what the book adjustment left me with.

Before adjusting I was trying to get a handle on which way to turn them for richer.

It's beginning to look like I might have to try 1 turn in from where they are now then drive it/ then one turn out from where they are now and drive it.

Twisty
 

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I'm glad I essentially had it right! I may be doing the same thing this summer on my "new" old 1200. Glad I didn't get rid of my sync gauges when I got the 1800.......
 

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The pilot screw adjustment controls fuel flow at low speeds and turning it in leans the mixture while turning it out richens the mixture. This adjustment will affect the entire operating range of the engine, but, primarily affects idle and low speed transition until the needle comes up.

hitechluddite's adjustment method is the same way I would do mine.


It appears that you may have dirt in the intermediate jets which will cause the same sort of problem you indicate, but, sticking slides will also cause a similar problem. Pull the slide covers off and inspect them for dirt, stickiness and wear and if that doesn't cure the problem you'll have to remove the carbs for cleaning.

Vic
 

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Vic,

Thank you very much for shedding some more light on the pilot screw adjustments.....

dean_3326 :12red::12red::12red::12red::12red::12red:
 

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Goldwinger1984 wrote:
The pilot screw adjustment controls fuel flow at low speeds and turning it in leans the mixture while turning it out richen the mixture. This adjustment will affect the entire operating range of the engine, but, primarily affects idle and low speed transition until the needle comes up.

carbs for cleaning.

Vic, that basicallyis about what I found by riding it this morning. Turning the pilot screws OUT richens it slightlyand in LEANS it out. Therefore they are fuel control screws and not air control screws.

I have opened the pilot screws to 2-1/2 turns out from seated and it runs pretty good there, at least no more farts asI roll the throttle on slightly.

About all I have left is a very slight slight sag as the slides firststart to open. I'm not sure if that is normal on a 1200 in 50° temps or not. I am going to ride it more as is, if it still sags as the slides open I will pull them and clean them.

Any chance shimming the needles up about .015" with small brass washers will help?



Twisty
 

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Vic, How come when I removed my pilotscrews once no petrol leaked out? I understood that the pilots were effectively air screws. I'm not questioning your ability as I know you are one of the most knowledgable guys here, but I'm feeling a bit confused myself.
 

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Eamonn1200 wrote:
Vic, How come when I removed my pilotscrews once no petrol leaked out? I understood that the pilots were effectively air screws. I'm not questioning your ability as I know you are one of the most knowledgable guys here, but I'm feeling a bit confused myself.
Disclaimer here; I'm not an engineer. I believe this is all part of how the venturie effect works. Think of your pilot screw as an air control valve of sorts. By letting a small amount of Control Air pass over the venturies of the pilot jets you let a small amount of fuel be drawn into the low-speed circuit. As you increase the amount Pilot,(control), air you're increasing the amount of fuel being drawn into the slow-speed circuit.

OUT= small increase in control air, larger increase in pilot/slow-speed fuel delivery.

Man how I miss the days of tuning throttle/slide cut-a-way, and needle tapers. Most of the newer carbs have multiple main jets and fixed needles. With vacume carbs, once you get past the excellorator pump the engine demand controls the flow of fuel as much as your right wrist..... :action:

O.K., I'm putting my head back into the bucket of water now... :waving: :gunhead: :waving:
 
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