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Discussion Starter #1
Hello, I'm new to the forums with posting however I have been coming here for a few years to reference I formation and research as well as look at others builds, have always found this to be a very welcoming community. So with that here is my first post and problem: I currently have a 1980 Honda cx500 custom(I believe, will have to double check), Mac 2 Into 1 exhaust with a cherry bomb muffler(2"in2"out I believe,used motomucci build as reference) with a silencer fabricated by my mechanic. Carbs were rebuilt April 1 1/2 years by my mechanic. I have since replaced the float bowl gaskets and the fuel connector rod o rings. The carbs are clean I have just serviced my throttle assembly, throttle cables, and choke cable. The problem I am having is my engine idle is too high. The bike fires fine, choke is pushed all the way in, no tension on the throttle, and the bike revs as if I'm giving it half throttle. I don't have a tac, just a speedo, and I have tried turning the idle speed adjustment screw(black plastic knob), and this does nothing, unless its almost tightens all the way in and the bike revs even higher. I turned the knob the other way so much as it fell out, but does not drop idle. I tried taking all cables off(throttle and choke) and the bike still idles super high. Checked my seals on the boots, and everything looks good, I upgraded my boot clamps to a heavier duty version so I do not think it is coming from an air leak. Any thoughts? I'm really tired of these carbs and thinking of upgrading to the Murray kit soon if I can't get these working, but I was wondering if the battery would need to be remounted and the air box removed to use?
 

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From what you say has been checked there has to be a vacuum port open. stuck carb butterfly or jammed linkage at the between the carbs

most likely the linkage . Don't work angry if you get frustrated just walk away,these problems can make a person feel like taking a hammer to the thing.

You will get it sorted sooner or later.
 

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There was a post a couple of years ago with the same issue. The carbs were mis-aligned with each other and binding the linkage. The resolution to the problem was to remove the carbs and re-align them on their brackets. When you separated the carbs to replace the transfer O rings, you had to remove the mounting brackets. (Or at least loosen things a bunch).

Try removing the carbs again and lay them on a flat plate on their venturi ends. Loosen the mounting screws and then re-tighten while still in alignment on the flat plate. Any flat surface will work, plate glass, table saw table, even a flat Formica table edge. Here is a LINK from our Wiki on carb tips and tricks that mention this.
 

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Discussion Starter #5
Thanks for all the help, I'll give the realignment a shot, I'll take a few breathes before taking off the carbs again(or putting them back). Murray I live in redding CA, taking the air of out is what I wanted to do in the first place I just need a ballistics battery so I do t have to remount the giant OEM one.
 

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Discussion Starter #6
Bam got it! Pulled off the carbs today and serviced the boots by doing 2 coats liquid electrical tape per boot. Found the left carb butterfly valve open about an eighth of an inch more than the right, so I tightened the choke spring until it closed the same as the right. Cleaned it all up a bit and put them back together and it now fires up great and I am now able to use the idle adjust screw and have my machine dialed in. Will ride like this for a bit to save up for the Murray kit and ballistic battery. Thanks you all for your help and suggestions!
 

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WELL DONE !!:eek:ccasion14::eek:ccasion14:
 
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