1982 CB900

[renegi9036]

Hello Again! Another MUCH bigger project on my hands as I learn a bit about these CB's. I believe I have a CB900F, the carb assembly matches what I have (one T fitment on the rack, with rails between the other carbs). I am in the process of re-assembling them.

A few questions:

1. Looking online at the fiche https://www.babbittsonline.com/oemparts/a/hon/506f7929f8700229747b8347/carburetor-assy...

I can't tell if there are o-rings on the joint assemblies or not? Fiche pic below. I did see this post here but doesn't appear to have a specific answer other than try and find a matching one? If someone could share the size of the o-rings roughly without me having to disassemble the sets of two that would be great! http://www.hondacb650.com/viewtopic.php?f=4&t=4747#p31276

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2. Does anyone know what these little parts are? They look like sleeves / connectors of sorts.

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[fizzlebottom]

Not sure which joint assembly you're asking about because there are 3 in the box you drew. There are 2 fuel joints (#11 and in the pic, and both of those do have 0-rings on both sides. Any time there is a metal fuel joint (not hose), there are o-rings. The other joint is just called a three-way joint set, and it is part of an air vent circuit which equalizes the carbs to atmospheric pressure, or that's what I've read. Others say it is the overflow for the fuel. Honestly, I have no idea at this point. I install it and don't question things anymore. The three-way joint does not have any o-rings.

The second question of yours: Those little nubbins are the actual needle jets. If you look at the Carb Component diagram, they're part of the #2 item - Jet Needle Set, which came packaged with the entire needle jet circuit.

[renegi9036]

Not sure which joint assembly you're asking about because there are 3 in the box you drew. There are 2 fuel joints (#11 and in the pic, and both of those do have 0-rings on both sides. Any time there is a metal fuel joint (not hose), there are o-rings. The other joint is just called a three-way joint set, and it is part of an air vent circuit which equalizes the carbs to atmospheric pressure, or that's what I've read. Others say it is the overflow for the fuel. Honestly, I have no idea at this point. I install it and don't question things anymore. The three-way joint does not have any o-rings.

Thank you for the info! I"ll see what o-rings fit!

The second question of yours: Those little nubbins the actual needle jets. If you look at the Carb Component diagram, they're part of the #2 item - Jet Needle Set, which came packaged with the entire needle jet circuit.

Well I took it apart but I don't see how this little piece could fit in there. Appears in the fiche diagram everything is in order for the needle jet? The little nub is hollow, I've includes some pics below

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[fizzlebottom]

I haven't removed mine in a long while, but I think you can see the needle jet in the mouth of the carb if you open the throttle plates. I also cannot remember if they come out down through the mouth or through the top of the carb, and mine is probably different than yours anyways.

[renegi9036]

You were correct, I was in the diaphragm but I think you meant the bowl. Yes, appears in parts fiche they are pressed into the main jets. I have another question but will start a new thread.