Author Topic: Carb part identification  (Read 1165 times)

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Offline evinrude7

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Carb part identification
« on: June 17, 2017, 12:13:04 PM »
If you look inside the throat of the carb on the right there is a "needle guide" that's missing. Compare it to the left. What is the actual part I'm missing here?

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Offline Jimray23

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Re: Carb part identification
« Reply #1 on: June 17, 2017, 12:15:37 PM »
Looks like maybe the needle jet pushing out on the left carb

--------------------------------------------------
Jim
1979 kz1000b ltd
    stage 3 cams
    pod air filters
    4-1 open exhaust(no muffler)
    full rewire
    dyna-s ignition
    dyna 3 ohm coils


Offline evinrude7

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Re: Carb part identification
« Reply #2 on: June 17, 2017, 12:22:05 PM »
Looks like maybe the needle jet pushing out on the left carb

--------------------------------------------------
Jim
1979 kz1000b ltd
    stage 3 cams
    pod air filters
    4-1 open exhaust(no muffler)
    full rewire
    dyna-s ignition
    dyna 3 ohm coils



the other 3 are all like that jim.  the carb on the edit* right is a 7A body replacing a currently broken 657A carb body.  so i'm missing a part in the 7A (carb on right).  what is the part i'm missing a "needle jet"?
« Last Edit: June 17, 2017, 01:01:38 PM by evinrude7 »
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Offline Jimray23

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Re: Carb part identification
« Reply #3 on: June 17, 2017, 12:35:01 PM »
Thats what it looks like to me.that may just be one of the differences between the 2 different carb types

--------------------------------------------------
Jim
1979 kz1000b ltd
    stage 3 cams
    pod air filters
    4-1 open exhaust(no muffler)
    full rewire
    dyna-s ignition
    dyna 3 ohm coils


Offline HondaMan

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Re: Carb part identification
« Reply #4 on: June 17, 2017, 12:35:33 PM »
Yep, that's called the 'needle jet'. They are sometimes available in the Keyster kits, but I suggest obtaining a real Honda/Keihin part so the calibration will be correct. The Keyster parts are notorious for not having correct tolerances, holes sizes. etc.
See SOHC4shop@gmail.com for info about the gadgets I make for these bikes.

The demons are repulsed when a man does good. Use that.
Blood is thicker than water, but motor oil is thicker yet...so, don't mess with my SOHC4, or I might have to hurt you.
Hondaman's creed: "Bikers are family. Treat them accordingly."

Link to Hondaman Ignition: http://forums.sohc4.net/index.php?topic=67543.0

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Offline Jimray23

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Re: Carb part identification
« Reply #5 on: June 17, 2017, 12:36:03 PM »
Pull the jet and emulsion tube and you will be able to see if its missing or just different

--------------------------------------------------
Jim
1979 kz1000b ltd
    stage 3 cams
    pod air filters
    4-1 open exhaust(no muffler)
    full rewire
    dyna-s ignition
    dyna 3 ohm coils


Offline HondaMan

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Re: Carb part identification
« Reply #6 on: June 17, 2017, 12:37:36 PM »
Thats what it looks like to me.that may just be one of the differences between the 2 different carb types

--------------------------------------------------
Jim
1979 kz1000b ltd
    stage 3 cams
    pod air filters
    4-1 open exhaust(no muffler)
    full rewire
    dyna-s ignition
    dyna 3 ohm coils



Well, the '7a' family of so-called "round top" carbs are all the same calibration and parts. The later ones after 1971 are more accurately built like each other, but they all have the same calibrations internally. The choke lever got moved from the left (#1) carb body to the opposite side at one point.
See SOHC4shop@gmail.com for info about the gadgets I make for these bikes.

The demons are repulsed when a man does good. Use that.
Blood is thicker than water, but motor oil is thicker yet...so, don't mess with my SOHC4, or I might have to hurt you.
Hondaman's creed: "Bikers are family. Treat them accordingly."

Link to Hondaman Ignition: http://forums.sohc4.net/index.php?topic=67543.0

Link to My CB750 Book: https://www.lulu.com/search?adult_audience_rating=00&page=1&pageSize=10&q=my+cb750+book

Link to website: www.SOHC4shop.com

Offline evinrude7

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Re: Carb part identification
« Reply #7 on: June 17, 2017, 12:47:13 PM »
Yep, that's called the 'needle jet'. They are sometimes available in the Keyster kits, but I suggest obtaining a real Honda/Keihin part so the calibration will be correct. The Keyster parts are notorious for not having correct tolerances, holes sizes. etc.

mark, jets r us usually wants a photo of the part to match it.  how do you remove them?  if you notice on their site the 657A or 7A is not listed.  in addition are these a standard size if not i have cb750k6.  what do i need?
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Offline Jimray23

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Re: Carb part identification
« Reply #8 on: June 17, 2017, 12:51:32 PM »
I think they normally push out towards the slide, someone correct me if im wrong

--------------------------------------------------
Jim
1979 kz1000b ltd
    stage 3 cams
    pod air filters
    4-1 open exhaust(no muffler)
    full rewire
    dyna-s ignition
    dyna 3 ohm coils


Offline evinrude7

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Re: Carb part identification
« Reply #9 on: June 17, 2017, 12:53:29 PM »
any suggestions on what to use to push it out? 
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Offline evinrude7

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Re: Carb part identification
« Reply #10 on: June 17, 2017, 02:02:07 PM »
got one out.  on the 657A and 7A they push from the top out through the bottom.  top being from the slide side or as orientated on the bike.  can anyone point me in a direction to purchase a few?  jetsrus does not have them. 
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Offline BomberMann650

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Re: Carb part identification
« Reply #11 on: June 17, 2017, 04:00:09 PM »
I thought the needle dropped into the emulsifier tube?  Its the end of the tube that pokes its brassy bit into the throat there?

Offline evinrude7

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Re: Carb part identification
« Reply #12 on: June 17, 2017, 04:09:34 PM »
I thought the needle dropped into the emulsifier tube?  Its the end of the tube that pokes its brassy bit into the throat there?

it does but there is also a needle jet beyond the main jet holder closer to the carb throat.  i found some on ebay.  just ordered a couple. 
cb750 k6 - ugly