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Discussion Starter · #1 ·
So after finally getting annoyed with the performance of my bike I decided to actually rip of my carbs and clean them to hopefully improve my bike's power output.



Took a while but I finally got them out and as I was inspecting them I noticed 2 holes on the left carb above the float bowl. The holes are only on the left side and are surrounded by black corroded aluminum. When I look into them I cannot see where it ends which makes me think that it could very possibly be going all the way through.



When the carbs are in my bike, it is starting and running fine. I only notice that it drops power as I rev it.



Are these holes normal and there's just corrosion around them, or should these not be there?



I've attached a couple pics to show them. My apologies on the photo quality, only had my blackberry to take pictures.







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Their normal casting holes that weren't drilled all the way through. It's there in case they used them for a different model bike.



It sounds like you need to do a full deep cleaning of your carbs. Years of use build up and clog the jets and passages as well as deteriorate the rubber diaphragms and O-rings.
 

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Discussion Starter · #3 ·
Ok good to know. I plan to do a full cleaning.



There just seems to be alot of corrosion around the holes and has caused the holes to lose a circular shape. Should I be worried about this spreading and causing damage?
 

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Discussion Starter · #4 ·
Is the manual instruction for cleaning the carbs sufficient for a "deep cleaning" or should I be doing more?



The Clymer manual suggests:

- Opening the float bowl, removing the main jet and secondary jet.

- removing the idle adjust screw and spring

- removing the top cover, piston and spring.

And soaking all the metal parts and air blowing them. They also suggested not to go further than this as it is easy to damage the parts.



Would this process be enough for a "deep cleaning" and to ensure my carbs are working well?
 

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Is the manual instruction for cleaning the carbs sufficient for a "deep cleaning" or should I be doing more?



The Clymer manual suggests:

- Opening the float bowl, removing the main jet and secondary jet.

- removing the idle adjust screw and spring

- removing the top cover, piston and spring.

And soaking all the metal parts and air blowing them. They also suggested not to go further than this as it is easy to damage the parts.



Would this process be enough for a "deep cleaning" and to ensure my carbs are working well?


No. Buy Larry's book and do the job right. The difference it makes is incredible.
 

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Discussion Starter · #6 ·
There is no online procedure I could follow?



I really want to get this bike running before the end of the week.
 

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Discussion Starter · #8 ·
The more I read the less confident I am getting on being able to do this. I feel kinda lost right now.



There seems to be alot of specialty tools that are needed and alot of Warnings that you need to be careful at certain points.



I am very new to mechanical repair, is this project suitable for someone like me?



My tools consist of a socket set, screw driver set, vice grip set, and an air compressor set.



I also have no idea if my petcock is accelerator pump/vacuum pump type which will melt with vinegar.
 

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ok,i think you can.i dont think vinegar will melt any of your parts.shep put me right,if im wrong.

forget the petcock,its not near the carbs.leave that alone for now[its your on/off valve connected to the tank.

take and post a photo of your carbs,we will tell you about the pump.i cant,someone local will.

which part,other than what iv said is difficult within the link to grasp,dont worry,we will walk you through it within a week
 

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Don't leave the air cut valve covers or the accellerater pump covers in the vinegar [ or commercial carb cleaner] too long. There's not a lot to clean on these anyway and they'll give you something to go on with while the carbs are soaking.



Don't put the diaghrams from these into soak at all and keep them away from the carb cleaner too, especially if you're planning on re using them.



Using the vinegar method the longer [within reason] you leave them in the vinegar the better they'll be cleaned. I usually look at 3 or 4 days soaking in the vinegar, taking them out from time to time to run hot water through them, then a soak in hot water, then blown out with an air line and back into the vinegar.



After a few days of this I'll start with the aerosol carb cleaner and the manual cleaning. If you have a low tool count and little money at least get the set of small welding tip cleaners or the guitar strings. The 3 tiny holes in the carb body below the throttle butterfly are very important and these and their connecting drillings are the most likely place to be clogged and consequently should get a fair share of your attention.
 

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here is a picture of some of the parts[inside the float bowls] you will remove prior to soaking



just be methodical,take photos and follow the link i posted
 

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Discussion Starter · #12 ·
Thanks for the help CXPHREAK and thanks bandit for the picture, help, and words of encouragement.



I was finally able to get hold of a decent camera and snapped a couple pics.



First, an overview of the carbs to see which carb model I have.







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Uploaded with ImageShack.us





I then removed some of the parts but didn't know exactly how far I should go.



Here's what I removed:





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The manual clearly states not to remove or adjust the mixture jet or slow jet. Should I still remove these?

If so, how do I remove the jet between the main jet and secondary jet? Could I use needle nose pliers or vice grips?







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I also wanted to remove the gasket from the float bowl but don't know the best way to do this without scratching the metal or ruining the gasket, how should I go about this?



Besides what is mentioned above is there anything else I should take out to soak and clean?
 

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You need to keep going a little. Take the accelerator pump off, that is on the other float bowl. And the ACV valves. They are under the covers on the side of the carbs. And back out the idle mixture screw. That is the one to the front, but outside, the float bowl. And pop the black rubber plug out of the idle jet. There is also a emulsion tube with a slotted top inside one of the towers. This can and should be unscrewed. Use ONLY a perfect fitting screwdriver in this slot. It is very easy to bungle up the slot on this brass part. I would advise getting a selection of hex flat type bits and use the largest that will fit.



Basically, you want to remove all parts that are held by threads before you ultrasonic it. Whether or not you separate the carbs from each other is up to you. If you decide to separate, you will need to bench sync and hook the choke transfer back up. If this is your first time, I would advise not to separate them and just put one at a time in the ultrasonic. Put the bracket you have off back on to keep the carbs from twisting out of alignment with each other.



You can just peel the gasket out of the float bowl with a sharpened Popsicle stick. Or if it looks OK, it probably is, and doesn't need replacing. They are a rubber type O ring gasket that typically doesn't wear out.



You will need some tiny drill bits to probe and clean the jets before you ultrasonic it too.
 

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First, an overview of the carbs to see which carb model I have.



Your '81 CX is a Deluxe, assuming it has the original carbs. The mechanism at the corner of the left bowl is the accelerator pump.





Here's what I removed:



See the orange, rusty lacquer in the float bowl. That same stuff is clogging the jets as well as the idle circuits inside the carb bodies. That's why it's not running well. The best thing I found to cut lacquer is straight Seafoam and an old toothbrush.



Also, reattach the bracket. Unless you have a leak at the transfer pipe o-rings, separating the carbs will add more work that you don't need.





R
 

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The manual clearly states not to remove or adjust the mixture jet or slow jet. Should I still remove these?

If so, how do I remove the jet between the main jet and secondary jet? Could I use needle nose pliers or vice grips?
The Clymer manual is a joke. Ignore it. Download the Factory Service Manual from this GoogleDocs site. (It appears you now need a Google account to access the site. Simple and free to do.)



To remove the slow idle jet (really an emulsifier) under the black rubber plug, you'll need a bolt extractor, a good penetrant, probably a propane torch, and a good bit of patience and restraint. A friend who's done it before helps a lot, too.



Concentrate on the rest for now. You may be able to get by without it, but understand that to be fully cleaned, that part needs to come out.





I also wanted to remove the gasket from the float bowl but don't know the best way to do this without scratching the metal or ruining the gasket, how should I go about this?
Carefully work a knife blade or sharp screw driver under the bowl gasket too get it off.





Besides what is mentioned above is there anything else I should take out to soak and clean?
Don't forget the "black banana" under the vacuum piston.





R
 

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Also, reattach the bracket. Unless you have a leak at the transfer pipe o-rings, separating the carbs will add more work that you don't need.





R
i agree with Randall 100%



take that on 2 years down the line,only if you need to
 

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The black banana itself needs to have it's back rubbed down on a piece of 320 grit on a sheet of glass until the bottom edge of it can make a good seal with the recess it fits into in the top of the carb.
 

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The black banana itself needs to have it's back rubbed down on a piece of 320 grit on a sheet of glass until the bottom edge of it can make a good seal with the recess it fits into in the top of the carb.
Only if it's been abused. I don't see any reason it should deform under normal use or long storage.





R
 

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The only way to be sure is to pass them over the paper a few times.



Only the perimeter needs to be flat, not the whole surface.



Larry says that the warpage is due to old age and a lot probably is.



Many I've looked at though put me in mind of a plastic parts tendency to shrink as it cools in the molding process and think that many of these have never been flat.
 

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Discussion Starter · #20 ·
Thanks for all replies. And for the manual - got some reading to do.



First some mentioned an ultrasonic cleaner. I do not have one or access to one. I currently have Honda carb cleaner, Seafoam, white vinegar, CLR, and an air compressor. I realize this doesnt have the same effect but I could get by with just these right?



I removed the back bracket because nearly everyone of my bolts were stripped when I tried to remove them. I first thought it was because the bike was old/the OEM bolts originally put in were cheap. But it could be because of the new mastercraft screwdrivers I just bought that are very sharp.

Anyways I will put it back on. Could I have already misaligned the carbs? Should I be worried about this?



Just to double check the locations, the blue is the accelerator pump and the red is the ACV valves, correct?



I should also point out that a past owner of my bike removed the vacuum hose to my petcock, so I currently do not have one (not sure if this is relevant to the accelerator pump or not)





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As far as poking holes, I have read that this could be done with nylon fishing line or guitar strings instead of drill bits. Has this been done with success?





And last question, what exactly is this black banana everyone keeps talking about? Don't really know what I should be looking for.



Thanks again for all the help. Going to remove as much as I can today and I'll take another pic.
 
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