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I have a chart (attached) that shows jet sizes and settings for the various CB350 carburetor versions. It shows the sizes for primary, secondary, and pilot AIR jets. When I review parts manuals I don't see air jets listed. Are they available for sale? How would I check the installed air jets for sizes?
 

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As far as I know - Jets were never sold by Honda as seperate items.

Jets are not a wear item in the carbs.
Unless they have been abused by a previous owner/mechanic they should only need the O-Rings that provide the seal to be replaced.
This would go for ALL Brass parts in the carbs.

The Offical rebuild kits from Honda only had the O-Rings, Fuel Inlet Needle and Seat, and the Float Bowl Gasket.
 

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The air jets are under the diaphragm on the top of the carb. They are pressed in place, not a replacement item and not something to play like the fuel jets can be.

Make sure they are open and clean, that's all that is required.
 

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Sorry I missed your last Question.
The size of the Jet for the (2) with the O-Rings is Stamped into them.

The jets will pull out using the spring bracket they hang from inside the float bowl.
Just look on one side or the other (there is a top and bottom but I can't remember which side has the size stamped)
The Spring Bracket holds pressure on them in place using the bottom 1/2 of the fuel bowl.

The last one is screwed in under the rubber plug and requires a very small jewelers type flat blade to unscrew.

NOTE: About the Air Tube under the jets with the O-Rings - one has what "LOOKS" like a screwdriver slot - IT IS NOT a Screwdriver slot.
To remove them they are PUSHED out from the inside of the carb tyhroat after removing the Slide Top Spring & Piston.
Use a wooden Chop Stick NOT a metal Punch.

To Clean out the very tiny holes in the #38 jet & the Fuel Tubes use a Single Strand of wire from a Lamp Cord Wire.
Yes it will be tedious but it will NOT deform or scratch the brass jets.
Steel Guitar strings are a BAD IDEA.
 

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Gonna have to bump this up.

really? No air jets available? Without the stock air box I would think those might need to be changed for optimal performance.

I have open velocity stacks on my CB350, with a 2into1 exhaust (with dirtbike muffler) that’s longer than stock. Still rich in the mid range but smaller mains make it too lean on the top end.

I’m thinking increasing all of the air jets would help
 

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You should start your own thread and post your jetting and setup. Decrease your primary main and increase your secondary.
Why do you think tampering with the air jets would help?
 

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You should start your own thread and post your jetting and setup. Decrease your primary main and increase your secondary.
Why do you think tampering with the air jets would help?
Stock jets. 35/70/105. I think larger air jets might help because I’m running rich at high RPM and low throttle
 

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RockReef your set up in my experience runs lean. Also two into one exhaust on these 350's usually degrades performance and makes it tough to tune. Honda didn't spec those carbs to be played with like you want too. They work for what they were designed for.
For fun and games you need a set of Mikuni's ..... they will keep you occupied for hours and hours. Couple vendors do packages with the correct throttle cable and in the ball park jetting.
 

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He needs to start a thread as his issue has nothing to do with air jets, and tampering with them will make his bike run like crap.
Raise your float slightly, install a hotter plug and 115 secondary main and see how it does

Edit: in your first post to this thread you made it sound like you tried different jetting. Is that not true if you're at stock?
 

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Why do you think air jets have nothing to do with how these motors will run with v-stacks?
It’s definitely rich. Because 1. It runs better cold
2. Plugs foul quickly
3. Smells rich

not gonna do Mikunis- already tried that and hated it - and not going to try and find an ugly stock exhaust and air box. Yes, I know bike would probably run better with those but still not gonna happen
 

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Honda 'pressed in' air jets have never been available without buying a carb body. I've mader some in the past but they are so small I lose more than I save. Do not enlarge the pilot or primary main jet air jets, I've tried, it doesn't work. (thinking about it I realised the stock air-box doesn't pose any restriction at low/mid rpm)
The secondary air jet is the only one that needs enlarging slightly, around 1. 20mm on CB360, I would have to look up size for 350.
Some 350's run better with 360 pilot jets (38) and a 65 primary main. Float level needs adjusting to compensate for today's fuels. 26.5 works, 27mm if you still have problems.
Personally I can't afford to make Mikuni VM's work properly, they need way to many parts replaced. I did get a set working on my Yamaha XS'650' but I made new emulsion tubes to a 'secret' specification (I forget what I did :D )
 
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