Won't idle or run without major throttle

Ok you got a 1980 special that has bs34cv carbs in it..... and I know from experience that those puppies have to be super clean....
you said you didn't sprey carb cleaner in the other parts for fear of the rubber o-rings deteriorating....
I had problems with my carbs until I removed the fuel/air adjustment screws in front of the slide , under the cap.... there is a tiny o ring and washer in that hole..... don't loose them ! sprey the carb cleaner in that hole and make sure it comes out the small holes in the throat of the carb..... by the butterfly..... also check the passageway in the float bowl, it often get's over looked but it is what supplies fuel to the idle circuit
that hole Must be clear to the bottom of the bowl.... ( its the one the tube slides down into. in the bowl.) I found both of those on my carbs were solidly plugged up. and it would not idle at all without the choke..... once cleared I had to re set the carbs completely
I did the dead cylinder adjustment to get the fuel air screws adjusted right on.... and then re set the idle screw on the side of the carb and also did carb synchronizing.... then it purred like a kitten !
.....
Bob.........
 
Yup. Correct but, that was a month ago ish... I took everything out before cleaning them this time - Yesterday - including all rubber parts, idle screw and o ring, slides, fuel float valve, and I taped the choke knob and fuel t really well so as to not get any carb cleaner on them.
I'll be taking them apart again to adjust the needle and will clean the crap out of those little puppies - again :) my can is almost empty so I'll try and find some of the stuff recommended.

I don't have a air compressor btw so I use canned air after the cleaner, which I notice can actually add moisture. I keep telling my wife that cleaning is not one of my strengths ;)

Thanks!!!
 
After you use the carb cleaner, spray something mild through like WD40 to flush the remnants of the cleaner out. In fact, I start out with the mild stuff. If it blows through OK, indicating the passage is clean, I don't even bother with the carb cleaner.
 
IMG_2113.JPG So my gas cap gasket is cracked, but the hole (vent) looks clear. ? Is a cracked cap seal bad?
 
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Oh btw. I re cleaned everything last night and moved needles up a notch to #2. But I ran out of time and light so I will test tonight and post back results. See pics of the needle business. I had new needles, springs, sir clip and washers so I put them in as well except for the washer. The new washers are too big... that is they don't fit in the hole!! Needles were identical. Crossing fingers tonight.
 
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Update. Much better!!! This is the first time in 4 months that I've gotten a steady throttle up through to 4500 rpms with no pause or hiccups!!! Awesome :)

Thanks to all you guys for the advice. I have a sound file as well that I'll upload as soon as I figure out how!!

Recap. I cleaned the crap out of everything again, moved the needle up one notch, which means the needle becomes longer and leans things out as per 5twins explanation. and I did put the original mains in. I know, I wasn't going to yet but the advice from 5twins was such that I figured it was a good move. Since my problem was mid range bobble, and it appears to be gone, I'd say the needle adjust did the trick!

Pulled plugs and mostly tan. Right one looked better than left, but both better than the normal black and sooty that I've seen most of the last 4 months.

:) :)
 

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