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Discussion Starter #1
hey guys! in working on a 84 honda cb650 I've taken the carbs off and cleaned everything up and out - reinstalled and as long as I have fuel going to it it runs WIDE OPEN until I cut the fuel off, or turn the switch off. vacuum leak?? or something not working in the carbs?? I can mess with the choke and get it to Idle down some but something def isn't right. The bike had been sitting for several months before I got it.

HELP!
Brad
 

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You need to remove the airbox and look into the carburetor throats and see if the slides are stuck open or if some other throttle return malady exists. When you twist the throttle does it snap back when you release it? Look for the obvious things first.
 

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ya I bet he has one or more carb slides in wrong if you can do that on that bike.




insert the little pin in the little groove that is cut the full length of the carb slide not into the cutout for your idle screw adjuster
 

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ya I bet he has one or more carb slides in wrong if you can do that on that bike.




insert the little pin in the little groove that is cut the full length of the carb slide not into the cutout for your idle screw adjuster
CV carbs don't have locating pins for the slides. The position of the diaphragm keeps the slide in the correct orientation.
 

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is there a way to put it together wrong so that it holds the throttle open?
... I'm too lazy to go outside and look at that old piece of crap
 

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If the diaphragms aren't seated properly when the tops are put back on, the slide(s) can sometimes still operate (half assedly) if there is enough vacuum generated to lift them.
You need to be sure the diaphragm is located in the right position and stretched into its seat where the cap will hold it down. You can usually slide the cap in a smallish circular motion to help seating. While you have them out you should hold the diaphragms up to a light and give them a little stretch to be sure there aren't any pinholes.
 

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... I've taken the carbs off and cleaned everything up and out - reinstalled and as long as I have fuel going to it it runs WIDE OPEN ...
:| had to put something together wrong, no? ... big assumption on my part that it was working correctly before the cleaning
 

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lol throttle linkage messed up? I remember it was a cluggie piece o'crap 2 cable throttle but i'm pretty sure you can only install one cable the wrong way

Brad! did you fix it yet? or blow it up
 

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Discussion Starter #11
Air box is off now. Butterflies work properly and if I push the pistons connected to the needle up they all slide back down at about the same rate. Slow to start with then they snap into the bottom position. Also if I try to twist the throttle while it's running it dies.
 

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Discussion Starter #12
Lol. Haven't blown it up yet. But it could happen!! It is a 2 cable throttle and you can put it on wrong but it's an easy fix to flip it back
 

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Discussion Starter #13
No it wasn't running at all before I got it. Jets were all clogged up and 1 of thefloats was stuck
 

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Discussion Starter #16
No petcock in the line currently. I'm working on the tank. I made a makeshift tank out of a water bottle ?
 

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I never tried that; on the one I have here I just cleaned the carbs, put it completely together, jump started it off the lawn tractor battery and it fired up for the first time in 8 years.
They are a pig to push around in the garage aren't they? absolutely nothing on that bike attempts to be light.
does yours have those funky 2 piece draw-back handlebars with the giant holes in the top yoke lol those are a joke
 

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maybe you should try stroking it and talking to it nice and if that don't work, clean the carburetors again
;) this will only be your second attempt and I think the record is 8 attempts.
 
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