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Discussion Starter #1
This carb goes on my Honda 350g. I took it apart "awhile ago" .On the right side of the photo (I think) I have the needle jet and on the left side I have the Main Jet holder. The NJet goes in the bottom hole and the MJ holder goes in the upper hole. Is this right? (sent here by "GB" or Bird76MoJo")
Thanks- hope the link works!



http://www.flickr.com/photos/ol55/3051069463/
 

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Sensei
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They appear to be oriented correctly to go into the nearest hole, However, Your terminology does not jive with mine.....The main jet aspiration (mixing) tube/holder is/contains the needle jet (goes over the slide needle) the other (thinner) tube is the aspiration tube for/and the secondary jet .......BOTH need to be cleaned better before re-installation.....All the small side-holes need to be clear and open...... If I remember correctly, there is another jet under that rubber button to the left of the other two that would also need to be cleaned...... I may be wrong, it has been awhile since I played with a 350 carb, but an authority here will correct me if need be.....Bill?.....
Steve
 

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Kind of hoped you could field this one Steve - I haven't had a 350 carb apart in a very long time, myself.
I'd hate to just talk out my ear......

Maybe a 350 guy could answer ??
 

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Mostly I wanted to clarify that the "needle jet" is the actual portal that is "sized" by the movement of the slide needle within it.... The "Main" jet is the largest jet (hole size) and is USUALLY directly underneath the needle jet....... There is another jet that handles the idle, and transitional fuel supply problems, (sometimes two additional jets)....That (those) would be the pilot and midrange, or pilot and idle, depending on where you learned about carbs)...... Regardless of what the correct nomenclature is, EVERYTHING must be scrupulously cleaned....., NOT just a quick blast of aerosol carb cleaner...... Steve
 

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That's a one piece needle jet/emulsion tube . the main jet screws into the bottom of it to hold it in place. slides in from top of carb from what I remember. If it slides in from bottom, its emulsion tube/ main jet spacer, tthe needle jett may be seperate and still in carb body. Its not a 3 jet carb so it doesn't have any rubber plugs.
It is a Kei-HIn carb?
That type of fitting is more common on Mikuni's
PJ
 

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Welcome aboard ol55 or whatever your name is... :p

I see you've found us and jumped right in. Good deal! You'll have those carbs figured out in no time ;)

GB :mrgreen:
 

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PJ...If you look at the picture, there is a round, almost flush rubber plug on the carb, center left near the jet passages.... I can't remember if that hides an idle jet on the 350 Kei-hins or not....But there definately IS a plug!..... See what I mean about nomenclature?...You call it an emulsion tube, I was taught aspiration tube...LOL.... regardless, it does contain a section that is the "needle jet"......... Steve
 

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Some might disagree here, but I always pulled out a wire bristle from a steel wire brush. Just one bristle. I have ALWAYS cleaned my jets this way and never had a problem. Just don't go all willy nilly on anything! :lol:

That and carb cleaner spray/dip/soak, and they're clean.

GB :mrgreen:
 

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I find soaking in carb cleaner to be best...( a 1 gal. "paint can" with a dipping basket available at MOST auto parts stores)..... Make SURE you DO NOT soak any plastic or rubber parts!!!..... Then "blow-through" the jets with aerosol carb cleaner and then compressed air....... You'll be pleasantly surprised if you do it correctly.....the carb will look NEW!..... Follow can directions, and don't soak TOO long....the carb bodies are sometimes painted or otherwise sealed, and it will remove that too, exposing the metal to corrosion....Which kind of defeats the purpose....
 

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66Sprint said:
PJ...If you look at the picture, there is a round, almost flush rubber plug on the carb, center left near the jet passages.... I can't remember if that hides an idle jet on the 350 Kei-hins or not....But there definately IS a plug!..... See what I mean about nomenclature?...You call it an emulsion tube, I was taught aspiration tube...LOL.... regardless, it does contain a section that is the "needle jet"......... Steve

Ahhh, I thought that was just an undrilled passage.
I've always called it an emulsion tube because it emulsifies the fuel before discharge. (and I think that's what AMAL called it)
Two countries divided by a common language :lol:
PJ
 

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Discussion Starter #13
Re: Kei-Hin 772a carb questions

More questions:1) the new bowl gaskets don't look like they willfit well. Is it ok to use the old ones if they don't leak?
Because I am running a velocity stack and a 2 into 1 exhaust, They gave me some larger jets. The jets I pulled out are stock. Since I have not run the motor except with junked up carbs, I was thinking of staying with the stock jets untill I see how it runs. Your thoughts? Also the 2 into 1 exhaust-Is it less restrictive or is it more for looks/sound? The motor was supposedly rebuilt, so I dont know if there are any internal modifications.

Should the rubber seals on the jets have grease on them when putting them in?

Thanks :D
 

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Discussion Starter #14
The extra jet sizes I have are 72 and 115. The stock jets are 68 and 105. The slow jet is 35. Could I use the 72's and keep the 105 without any problems?

Thanks
 

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Make sure the bike is in a good state of tune before making any jetting/exhaust changes. Check timing, good/new plugs, verified fully charged battery, etc.. I'd want to ride it through all of the gears before I made any changes, to make sure it would rev all the way to redline in every gear, under load. Then and only then would I rejet.

BUT, that's just me.

GB :mrgreen:
 

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Discussion Starter #16
Thanks GB! Did you notice I put two posts back to back? Sorry for the confusion.
:?:
 

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Discussion Starter #17
Is there any trick to removing the slow jet? There is no access from the top of the carb. It is the jet that is under the small plastic plug. Still working on this...
 

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What little knowledge I have is on CB450 and Mikuni roundslide carbs. My only idea would be for you to post a picture if possible, and let more knowledgeable people point you in the right direction. :?:

There should be a manual here somewhere, but if not then asking nicely sure can't hurt.. ;)

GB :mrgreen:
 
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