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Discussion Starter #1
I'm having a problem with my 76' CB200's petcock and fuel lines. The petcock only lets fuel out of one of the outlets, one for each carb, and then sucks fuel through the other line. I put some clear tubing on it just to test and there is also alot of air bubbles in the lines. Does a vent need closed or open or could this be something else?
 

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not sure if the cb200 has this but some petcocks are vacuum operated (t500 for instance - switch it on but no fuel comes out until the bike is kicked over). If you do have a vacuum operated petcock then one line will be for engine vacuum and the other will be for fuel. Typically the outlet on the carb is much smaller than the fuel outlet and there will be a common feed (usually on banked carbs).

The only other thing I can think of is that inside the tank is partially clogged and the gasket is warped so when the engine wants fuel it is just sucking air from the open outlet as well as what little fuel can get through the tank.

Call honda and find out if they still can get cb200 petcocks. I know cb750 and 550 are still available.

somebody with a cb200 chime in and help out as I am in foreign territory.
 

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The cb200 uses the same type petcock as other hondas of thet age. The 2 outlets are both fuel. I suspect a venting problem. Try the same setup with the gas cap open. If you still have the same symptoms then pull the petcock and look for something clogged in the fuel pick-up tubes. If the symptoms go away with the fuel cap open then the vent in the cap is plugged. I would check the vent hole in the underside of the cap for rust dirt etc.
Ken

AHRMA 412
Vintage racing - old guys on old bikes
 

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Discussion Starter #4
Thanks for the quick responses. I took the tank off and then the petcock came off and I cleaned it all out. Blew carb cleaner through all of the holes. Put It back on and still the same problem. It lets fuel out one outlet and sucks through the other. If you plug the line that is flowing it pulls fuel back up that line and starts flowing fuel through the other line. Its like its siphoning from one outlet to the other. Also it does this when the gas cap is open and when its closed. Any Ideas about what is going on here?
 
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