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Hey guys. So, I bought a 1979 Honda Cm400A. Very happy with it. After a couple days, sometimes the bike died when it came to a complete stop. It would take 30 seconds to die. I could hear it slowly decreasing the idle. I figured I probably need to adjust the RPM's on that thing. The thing is, I can't seem to find in the carburator where to adjust the idle. I saw on a bunch of youtube videos that the idle adjustment screw is "goldish", but none of them are in my bike. Is there any way anyone that owns a Hondamatic could take a picture of the location of the idle adjustment screw?
This is my first post and I really look forward to learn about my first motorcycle here.
Thank you all!
 

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In the center of the two carbs at the bottom, you will find a black knob for the idle speed adjustment.
 

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Idle in neutral should be 1200 +/- 100. Idle in gear since this an A model should be 2500 +/- 500. When the bike is put in gear the change switch sends a signal to the CDI box to change the timing from 7.5 degrees to 15 degrees to increase the idle to compensate for the load. On my CB 400a the high idle was around 1800 but it ran good so I didnt mess with it.

Hope this helps.

Bill
 
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