Topic: 78 CB550 engine adjustment screw?

[chstr1]

I was having problems with my choke not fully closing, in fact only about 25%.  Needless to say it was a little hard starting.  I had a broken cable plus the previous owner did not have the end of the cable attached on the carb end, so I could not get the butterflies to close.  That is figured out and it starts like a charm, but I made some adjustments in the screw I have pictured here.  Now, of course, I am not sure how it was set, and being I don't know what it is for, I could use some advice.  It sits just behind the 2nd and 3rd carbs where the choke lever connects to the butterfly arm.


Can anyone tell me what this screw adjusts? Obviously is has a significant purpose, and being I have some idle speed and throttle control issues, I have a feeling the two are related.  I know where to adjust the idle, but what does this control.  Thanks for your advice on my earlier adventure, and hope someone has the answer to this poser!

[TwoTired]

When you actuate the choke, a cam pivots into position against this adjustment screw.  The screw setting then increases the idle setting while the choke is actuated.  When it is warmed up and the choke fully disengaged, your main idle stop controls idle speed setting.

From the Honda manual:

Fast Idle:
1. Remove fuel tank.
2. Pull the choke knob out fully and turn the adjusting screw until it touches the stopper.
3. Push the choke knob in and turn the adjusting screw in 2 1/2 turns.  Fast choke idle speed: 3000 -4000rpm

[chstr1]

Thanks;

 that mudy nr why it's running at 6K RPM when it is warmed. I will need to back off the choke idle so it will disengage and let the main idle do it's job.  It will be the first time since I got the bike last June it will start and idle like it is supposed to. 

However, now I have another problem, but you can't do much about it.  I guess there will be no test ride today.