as I wrote in the "3300 low power" thread we are continuing to troubleshoot the low RPM.

It has already shown that obviously a rather small main jet (245) was installed. I will get a selection of nozzles, especially the 255 default nozzle, as well as 260, 265 and 270 to try.

Someone told me the nozzle needle also comes in two versions, one with many mounting grooves on top and one (eco?) with only one mounting groove. Which is the right one for the 3300 ?

The fuel supply is best from the carburetor comes with the electric auxiliary pump about 500ml in about 20sec, if you have removed the float bowl. That should be enough.

The vacuum can with the rubber diaphragm worries me, like everything that is not used, but also about 12 years old.
How can I check if the vacuum can still does its job properly ?
My idea would be to look with a borescope in the air intake of the carburetor to see, if when you accelerate max., the cylinder in the carburetor goes up and how far ?! Would this be a feasible idea or is it better to do otherwise?

Thank you.



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that carb comes out very easily...  i took mine out so my mechanic could clean and inspect the inner workings- including a thorough inspection of the diaphragm boot...  also, there are divots in the diaphragm that must be oriented correctly during install.

he showed me how to inspects the diaphragm.  he inspects it every time he takes a carb out, as this is a known cause for the cv carb to NOT self adjust. 

he is a harley shop owner and sole mechanic so he sees hundreds per year.   i've reached out to him to ask him your bing carb questions.  more to follow...


Thank you !

The diaphragm is old indeed but never used before, 12 years as the Crab itself.

Are there more parts to change that are fading away ?

Is the Bing common for harely d. ? Can I get spare parts from them ?

Getting spare parts in germany for bing is difficult and time consuming ....



he’s traveling on holiday, but texted - “diaphragm for sure or incorrect float height”

parts are around on innerweb for ordering your motorcycle carb parts, yes.  and a Rotax sometimes has twin smaller bings.  I found a good website in a thread on bing in the Jabiru forum here.



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