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More carb troubles, engine won't return to idle revs

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Laverdaroo:
Thats the chap.


I am TAYLOR! :D

billdn:
Sorry to return to this but still having problems! >:(
I watched the videos mentioned and even carefully read the Vintage Biker piece on setting up the carbs- no joy still won't idle.
I've tried BryanJ's revised carb set up still no joy.
It just won't return to idle speed of 1200rpm. rev it to 2000rpm and won't drop, rev it to 300rpm drops to 2000, rev it to 4000 drops to 3000rpm. I've disconnected cables and it still won't drop, so can't be cables! and revved by hand.
I've adjusted air mixture screws to 1 1/2 turns out and nothing.
But again, press the top of the brass nuts on top of the sliders and you can get the revs to drop but then drops too low and stalls. it can be reduced by adjusting idle screw but continually doing that is not right, obviously!
Is it possible I've reassembled wrongly the sliders but they to be smooth enough in their action?
Is it possible to get the main spring the wrong way round but don't see how, it closes the carbs with a quick action?
Frustrated of Sussex

Oddjob:
How far down have they been dismantled? Sounds like a lifter arm problem, maybe one of the internal springs is missing or corroded to the extent it’s not pushing the arm down enough when it’s lifted. The fact pushing down on the top nut reduces the revs would make me suspect this.

McCabe-Thiele (Ted):
If pressing the brass nut down drops the revs then I suspect you have something not assembled correctly  in the slider mechanism / links. There is a spring as well as the ball cups either side. Did you remove the lever bolted to the slider top that has the locking tab?
Even though the throttle return spring is quite strong the lever mechanism has to be working freely via the links to shut off effectively at all temperatures.

You have three links with spring & cups on each carb. One attached to the slider inside plus two external ones on the alloy body with the plastic cross links. If just one of the four sets of three links is not assembled correctly it could explain your issue. Twelve links in total that need checking.
Another thought have you removed the fast idle cam & lost the little ball bearing?

Update:- looks like my reply duplicates Kens thoughts.

billdn:
Cheers Ted and Oddjob,
Have stripped down and cleaned slider assembly, lubed etc and reassembled.  Couldn't really see much wrong, no major debris and everything in the right place , thankfully. Did notice that the 2 springs in the slider arm although are same length were slightly different colours, so swapped them around , TTYL anything now.
Ted, still have little ball bearing in choke mechanism too.
Odd job, was full strip , everything apart including slider arm ..

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