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Slider problem on Carb

JtgHawk

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Afternoon everyone,
I just got a 1975 CB 750 and I’m cleaning the Keihin carbs and after cleaning them I noticed that when I install the slider with Needle valve it will not seat into the carb body all the way. It stops before it bottoms out like the other carbs. It is possible that the needle jet in the body is damaged and will not allow the needle valve to extend all the way, but I can’t see any damage. Attached are a few pictures to help explain what my issue is.
Any help would be greatly appreciated

First picture is the #2 carb that seats properly
IMG_1676.jpeg

This picture is from the problem carb (#1) if I apply pressure to close the gap further, the slide gets stuck.
IMG_1675.jpeg
 
Are you sure the needle is entering the hole in the jet? Or is the needle bent? I notice the choke plate in the trouble carb. Is it interfering with the slide?
 
Are you sure the needle is entering the hole in the jet? Or is the needle bent? I notice the choke plate in the trouble carb. Is it interfering with the slide?
Yes, the needle does fit inside the jet and the choke plate is not interfering with the slide. The picture did make it look like it was though.

Upon initial inspection the needle does not look bent however I switched out the needle for one from another carb and it does not bind up. There must be the smallest bend in the needle that I cannot see. Amazing how small the tolerances are on the needle fitting into the jet.

Thanks for the idea of inspecting the needle further!
 
Glad it helped.
I also just got a '75 and went through the carbs. I strongly recommend replacing the o-rings on the fuel transfer tubes while apart.
That's why I got to do my carbs twice.....
 
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