4th carb out of sync

akis1962
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4th carb out of sync

Post by akis1962 »

Hallo everybody.I have a stock 79z usa.When the engine warms i have 2000 rpms.So i am out of sync.Trying to bench synch ,i realise that the 4th carb cant close as well as the others.>i have separate the block and i have change almost everything.Rod,plates,everything left or right touching the carb.Also i have correct fast idle distance.I have 5 completly closed carbs but one a little open-just-.The plate just touching the hole.But i cant make any other adjustment on 4 carb.I have a spare block so i have spares.The only modification in my carb is washers under the needles and 37.5 orifices on the pilot jet-not 35_.
I must tell that i try for 4 years to repair them.The carbs work very well except the High idle.
Thanks for your interest and your valuable Information .I have spend some years reading all the Library.And i will continue because i find such a interesing minds working all together.

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NobleHops
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Re: 4th carb out of sync

Post by NobleHops »

Greetings Akis, and welcome! Sorry I can't be much help, someone will come along to help shortly I think.
Nils Menten
Tucson, Arizona, USA '80 CBX, sort-of restored :-)

tevan
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Re: 4th carb out of sync

Post by tevan »

Number 4 is not adjustable except by adjusting the idle speed. I think you need to open all the other carbs up and then adjust the # 4 with the idle adjustment screw where is just is opening #4 up and then adjust 5 then 6 then 3 then 2 then 1. Get them as close to each other as possible. Make sure you sych them on the bike.

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Kool_Biker
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Re: 4th carb out of sync

Post by Kool_Biker »

Hi Aki
I also have a CBX Z and live in Athens. May be you have seen some of my postings in ICOA.
I would be happy to connect and see if I can help. I have played with these carbs few times.
Do let me know and feel free to PM me.
Regards, Aris
Aris Hadjiaslanis
ICOA # 6309
Berkshire, Windsor

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spencer
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Re: 4th carb out of sync

Post by spencer »

tevan wrote:Number 4 is not adjustable except by adjusting the idle speed. I think you need to open all the other carbs up and then adjust the # 4 with the idle adjustment screw where is just is opening #4 up and then adjust 5 then 6 then 3 then 2 then 1. Get them as close to each other as possible. Make sure you sych them on the bike.
I wanted to say the same thing, but Tevan said it so well that I can only agree with him.
SCH Rochester, MN

daves79x
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Re: 4th carb out of sync

Post by daves79x »

If you are saying that with the carbs separated, #4 butterfly will not close, then the throttle plate need adjusted (not uncommon). You do this simply by loosening the 2 staked screws that hold the plate in place. Then snap the connecting arm a few times to center the plate. Holding everything still from there, tighten the screws and the plate should snap shut tight in the carb throat.

If you are saying that with the rack connected you can't get #4 to close, then Tevan's advice is correct - the other 5 plates are holding #4 open. You START by adjusting #4 with all the others being opened slightly further, since any one that's closed more than #4 will hold it open.

Your problem is one of these two things, unless you have incorrectly installed the connecting linkages.

Dave

akis1962
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Re: 4th carb out of sync

Post by akis1962 »

This is not so simple...I know how to adjust the throttle plates.Their holes are bigger than the screws.i have also change 3 spare plates to examine if the problem is the plate.The 3,2,1 carbs from the other bank are separate because i have remove the linkage.5and 6 doesnt create a problem to the 4.The linkage has the correct parts inside of it and with the right way.I know that from the distance is very difficult to aproach the problem but i believe that there is people at the club with a vast experiance.Grateful.
Regards

daves79x
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Re: 4th carb out of sync

Post by daves79x »

Well, hopefully 'those people' will show up!

Dave

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asacuta
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Re: 4th carb out of sync

Post by asacuta »

I'm no expert on carbs, but maybe if you post some pictures, the experts here might see something amiss.
Al

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spencer
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Re: 4th carb out of sync

Post by spencer »

akis1962 wrote:I know that from the distance is very difficult to aproach the problem but i believe that there is people at the club with a vast experiance..
Regards
Yes, there are people here with vast experience. You have been talking to them. Dave is probably the best CBX carburetor guy here. Listen to his advice.
SCH Rochester, MN

tevan
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Re: 4th carb out of sync

Post by tevan »

spencer wrote:
akis1962 wrote:I know that from the distance is very difficult to aproach the problem but i believe that there is people at the club with a vast experiance..
Regards
Yes, there are people here with vast experience. You have been talking to them. Dave is probably the best CBX carburetor guy here. Listen to his advice.
I second that. He has forgotten more then I know about these bikes!!!!!!!!!!!!

akis1962
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Re: 4th carb out of sync

Post by akis1962 »

Dave please accept my apologies .First i understand very well the value of your answer.I have the knowledge to understand it because you somehow teach the carb subject and i learn from you.Second i dont write in my native language so i cant express very well my thinkings.
Sorry a thousand times

daves79x
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Re: 4th carb out of sync

Post by daves79x »

Please, no apologies needed. I just get frustrated sometimes trying to answer as many of the tech questions as I am able.

If you were closer I'd be happy to help you sort your carbs out. At this point, I just don't know what else to offer. There's something simple there staring you right in the face, you just have to see it. If you can offer additional info I'd be happy to comment.

Dave

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spencer
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Re: 4th carb out of sync

Post by spencer »

Since you live in Athens, one of the favorite cities I have ever visited while in the Navy, you should take the offer of help from Aris. See the quote below, from earlier in this thread. I am sure he could help you.
Kool_Biker wrote:Hi Aki
I also have a CBX Z and live in Athens. May be you have seen some of my postings in ICOA.
I would be happy to connect and see if I can help. I have played with these carbs few times.
Do let me know and feel free to PM me.
Regards, Aris
SCH Rochester, MN

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spencer
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Re: 4th carb out of sync

Post by spencer »

And by the way, I respect how hard it can be to communicate in a foreign language. Your English is wonderful. I only wish my Greek, was as good. If I had to communicate in Greek, I would be lost. :bow-yellow:
SCH Rochester, MN

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