Play in Choke connecting plate 1 and connecting rod

[Johnny280]

Thanks a lot for everyones input so far. A lot of stuff I have to think about. I will try to analyze the clamping situation first and fiddle around with all your different methods, then probably get the carbs out to check the linkage for canting. 

@siteunseen: The carbs are suppose to be ZTherapy rebuild ones and the rubber hose seems to be of the right type - flexible silicone ones. Regarding the Choke attachment. Yes, i replicated that one after wasting half a day building my own idea (wasn't aware that the internet had a pretty good solution). Mine was working but too bulky to fit under the console. One day I will place an order with ZTherapy and on top get one of those famed DVDs.

@Captain Obvious: The flooding was pretty close to us but luckily we dodged that bullet. It was more to the south but a lot of the water was flowing down via the rhine which is only 300 meters away from our place. Waterlevels were not critical but unusually high for summer. Fortunately yesterday was only constant heavy rain (real German summer).

I read somewhere that original SUs are first opening the butterfly and then enriching the mixture. Are our Hitachis the same in that regard?

[Captain Obvious]

I just took a look at a pair of (Hitachi version) SUs here, and the throttle opening cam starts to push on the throttle linkage at close to the same time the other linkage  starts to move the nozzle down. So the answer seems to be... "Pretty much at the same time."

Depending on where you have your nozzles set (how many turns down) and how you have the throttle opening linkage arm bent, you might get one a small amount ahead of the other, but not by much. I wasn't there when they designed it, but I suspect they were aiming at "the same time".

[Johnny280]

Update: 
I removed the carbs and had a good look at the linkages. There were multiple things wrong:

1. the choke cable was indeed too tight and was preventing the spring to get rid of the play and keeping the nozzle completely up.
2. a wrong bend in connecting bar A resulted in the sticky nozzle situation. After some time I was able to bend it in a fashion that a) the nozzle stays up b) the nozzle is not sticky c) both nozzles move the same amount
3. had a look at the connection rod to the butterfly and bend it to match the specs in the service manual (between 0.59-0.69mm butterfly opening on max choke)

Next step is to refit the carbs and get the choke cables on a little bit more loose then the last time. 

The original plan was to just swap the SM needles to SB needles to see if i can lean out the idle (had some filthy rich idle hot @10.5 while cruising @16+) a little bit while keeping a richer mixture at full throttle and cruise - lets see if that works out. 

Thanks again for the input and the reassurance that there was nothing wrong with the linkage.