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Carb secondary main jet

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Murf:
Hi can anyone tell me which way up the secondary main jet should go.
It has 2 groves one for the o ring the other for the clip, the groves are positioned at different distances in from the ends giving a wide land  at one end and a narrower one at the other. The old o rings are in the grove that will place the narrower land in the carb body next to the emulsion tube and the wide land in the float bowl, is this correct?
The internal jet bore is machined differently at each end so it is critical. 
I ask as I  don’t trust anything I find on this bike, and I feel they should be the other way up.
Thanks for any help.

McCabe-Thiele (Ted):
I am confused by your description, do you mean the main jet that fits after the Emuslion tube where the wide bowl clip is fitted?

I found this useful even thought its for a 400, if you zoom in on the photos at the relevant ( rebuild near the end) page you will see the counter sinking on the inside of the jet. Very important to lube the O ring I used a smear of red rubber grease on the outside.  Any excess can easily be wiped off then it's fuly home.

https://www.vintagebikebuilder.com/cb350-400f-carb-rebuild-demonstration.html

Nurse Julie:
when the jet, or guide, which is what I think you are referring to is in the right way up, any writing on the end of it is facing you.
Edit..... Or do you mean the main jet?

Murf:
Thanks
I think I have my answer from Teds rebuild link, it looks like the end with the longest land goes towards the float bowl, the larger diameter internal drilling is also that end with the small drilling (the actual jet orifice) towards the emulsion tube. The article in Teds link is an excellent article.

Thanks Julie but there was no markings on the end of my jets just on the side.

McCabe-Thiele (Ted):
I'm not 100% certain but if you have no  O ring in place and try to fit it upside down I don't think it pushes the emulsion tube fully home.
I have a memory of having the same doubts as you before it became sort of obvious once I'd read the link.

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