Question about 1972 Honda CB 250

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1973 Honda CB450 carb problems

Hey guys. I got my Dad's 1973 Honda CB450 as a gift/restoration ... The carbs are way out of wack on it ... is there anyone out there who has the factory carb settings for this bike ?

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Turn the air screw and throttle screw all the way inward until they LIGHTLY seat. Now open each of them one and one half turns. That is the factory setting. Chances are the carbs are gummed up with varnish from evaporated gas. Disassemble the carbs and soak them in denatured alcohol for 30 minutes. Now clean them with spray carb cleaner from the auto parts store. You need to be sure all the jets and fuel circuits are clear. You may need a service manual sometime. Here is a website that looks like it may have a free download. Even if they want $20 or so, a service manual is handy to have around.

Posted on Feb 02, 2010


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Posted on Jan 02, 2017


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