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Discussion Starter · #1 ·
Howzit guys.

I am new at this, so this might be a newby question.

I have a '81 cx. It runs beautifully, but my right bank is running quite rich.

I don't know anyting about setting these carbs. Can someone point me in the right direction please?

My left back burns sweetly. Just my right bank is burning very black.
 

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Howzit guys.

I am new at this, so this might be a newby question.

I have a '81 cx. It runs beautifully, but my right bank is running quite rich.

I don't know anyting about setting these carbs. Can someone point me in the right direction please?

My left back burns sweetly. Just my right bank is burning very black.
The first thing I would check is the float levels. Probably give the carbs a good cleaning

and see what that does for it. There is a book available through this forum that will help

you do the carbs. Take the carbs apart and clean every orifice you can find, set the float

levels and start with the idle adjust needles out about 2 and 1/2 turns. Make sure the jets

are in the correct locations. You will get many responses and lots of help from forum members.
 

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Discussion Starter · #3 ·
Thank you for the quick responce Old Okie.

Any idea where i can find this book you mentioned?

I did clean the carbs three weeks ago, but I didn't adjust anything.
 

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Many things can cause a rich cylinder. Stuck closed choke plate or carb crudded up or maladjusted is a likely cause, plug cap resisters corroded, or even a bad plug are also possible. Can you smell gas or notice any dripping at below the carbs? The key is to deduce which of the simpler possibilities to chase down first. How about a little more info? Did this condition suddenly appear on a daily rider? Or was the bike just brought out of an extended dormant period (more than a year or two)? Done any recent work on the carbs? Is it running okay at higher rpms? Seem to have a normal amount of zoom zoom? A lot of input is helpful to limit suggestions like "lap your valves" when all it needed was new spark plugs, eh? Also, since "we" don't know anything about your capabilities or mechanical experience, don't be offended if some advice borders on the real simple stuff you may have already covered yourself. Help us get to know you and your bike and you'll get plenty of advice here. And we're a nosy bunch, soooo, where are you from? If you're near Sacramento, CA, or Appleton, WI, you just hit the CX/GL jackpot . . .
 

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Since the bike is a 1981 and it is the right side carb you might have a bad diaphragm in the vacuum petcock which can allow fuel to bypass the carb and be drawn directly into the right hand cylinder.



The vacuum line runs from the petcock to the right hand carb, if you were to remove the line from the carb and it had gas in the line this would be the problem.



If the ports on the petcock and carbs have been blocked off and there is no vacuum line then someone has converted the petcock to manual and this would not be the problem.



Another thing that will cause a rich condition is if the rubber "hat plug" is missing from the idle jet tower inside the float bowl,,even if the plug is in place if it is not fitting tightly it could still cause problems.
 

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Discussion Starter · #6 ·
I like this place already


I've been a CX fan for only two years and never realy had issues with them. This is my second CX and I baught the bike with this problem. I know the bike has been standing for two years before I bought it. The previous owner rebuild the engine and sold it to me.

I notice fuel coming from the float-chamber drains when I leave the fuel valve open when the bike is parked. I am in the process of sourcing a carb kit, but they are not readely available in South Africa. The bike runs fine at all revs. It is slightly down on power, but only slightly. I did assume it to be the overfueling. The bike has just been serviced and the plugs are in good shape. The bike is a daily runner and does 60 miles each day. I am learning on the mechanical side, but the knowlege is limited at the moment, so all questions and remarks are appreciated.

I will gladly give as much info as possible.
 

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Gas flowing from the bowl drains is a sign that the either the floats are sticking down or bad ,,or there may be some dirt or crud in the float needle valve which is keeping the needle from seating properly,,you will probably need to remove the float bowls to fix this. This would also indicate that you do not have a vacuum petcock or someone has converted it to manual or it is not working properly. If the vacuum petcock was working properly no fuel could enter the carbs without the engine running.



It may be just as easy to remove the carbs from the bike and if you do this it would be a good idea to clean the carbs while you are at it.
 

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Discussion Starter · #8 ·
I cleaned the carbs out about three weeks ago specificaly because of this. The float needles didn't look bad at all, but the problem remains. I didn't strip down the carb completely as I am not as experienced yet. Hence my enquiery
 

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Do you know if you have a vacuum petcock? You would have a small hose running from the petcock to the right hand carb, another small hose routed down to the bottom of the bike and a larger line to supply fuel to the carbs if it is a vacuum petcock.



If your float needles are seating alright,,the floats must be sticking or are not adjusted properly if the drains leak when you leave the petcock turned on.
 

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I cleaned the carbs out about three weeks ago specificaly because of this. The float needles didn't look bad at all, but the problem remains. I didn't strip down the carb completely as I am not as experienced yet. Hence my enquiery
hi,and welcome from spain.

can you first update your signiture line,include your location in south africa,and your bikes details.

here is a link you can follow to re-clean your carbs,there are a few bits that you need to remove to stand a chance of it working.

linkhttp://globalcxglvtwins.hostingdelivered.com/viewtopic.php?f=19&t=140



plus a newbie present for you
a whole page of carb info


http://globalcxglvtwins.hostingdelivered.com/viewforum.php?f=19





on a side note........you into the rugby?
 

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Discussion Starter · #11 ·
hi,and welcome from spain.

can you first update your signiture line,include your location in south africa,and your bikes details.

here is a link you can follow to re-clean your carbs,there are a few bits that you need to remove to stand a chance of it working.

linkhttp://globalcxglvtwins.hostingdelivered.com/viewtopic.php?f=19&t=140



plus a newbie present for you
a whole page of carb info


http://globalcxglvtwins.hostingdelivered.com/viewforum.php?f=19





on a side note........you into the rugby?




Thanks for the links.

I am very much into rugby. lol
 

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Since it wasn't answered, HERE is the link to Larry's book.



He's the guy that restored my G-Loria. (another selfish plug to clicking the picture in my signature line)




Joel in the Couve
 

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Sounds like overflow to me. You probably need to clean the needles and seats again. But first...

Also not mentioned yet...........

Adding an inline fuel filter between the petcock and carbs will help keep tank rust and crud from preventing the needle and seat sealing. If you have an old one from a PO replace it anyway in case it has been installed backwards at some point and had crud gather on the "out" side.
 
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