Easy
I don't have a good answer for you I tried a combo of different sizes and lengths dia. What I found is what I posted. The only thing I didn't do was the diaphragm bottle and I think that might have been different. I pulled my bottle off today and plugged the hole with an aviation 1/8" pipe plug( anodized aluminum) I also smoothed out the inside of the manifold where the plug stuck out in the bore. I would recommend you try for a 69 to 70cc including the hose as that seemed the best. I did find that if the bottle was up over the head( mine were made out of steel) I never collected liquid in the bottle. I also found that it smoothed out the low rpm what I did not like is it takes a long time for the idle to stabilize after riding and coming to a stop. To me the bottle was not worth the trouble, but was fun to experiment with.
I didn't answer your question very well but I tried to.
norman

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