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Type of carburetor

Halcyon402

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Hey guys. I currently have a cb750 k6 and am doing a carb rebuild. I am beginning to think that the carbs on this bike are not stock. The manufacturer is Keihin and it has VE 75ABW0 with the B boxed in. Do you guys know what these carbs came off of so I can get the correct rebuild kit? I'm currently looking at the manual and the carbs on here look nothing like the ones I have. Thanks for your help guys.
 
Send a picture. and send the number on the motor then I can tell exactly what year the motors is.
 
Here are some pictures:

The third picture is of the inside of the carburetor. It seems to me to be pretty clean. I check the main jet and the small jet and they seems to be unclogged. I am unsure if the carburetor is the problem that's preventing my bike from running. Thanks again for all of your help dirtdigger.

carb 1.jpgcarb 2.jpgcarb3.jpgengine 1.jpgengine 2.jpg
 
Your motor is a 1976 motor K6. Those are not the correct carbs for the motor and I can not understand why anyone would want to torture themselves by purposely putting them on a bike. lol If I was you I would look on ebay for the correct carbs and make your life 10x easier. Those vacuum carbs were junk when they came out are a pain to try to tune...especially when they are not even on the right motor.
 
I dont know for sure but honda didn't start using them till the dohc motor and most 1979 honda models came out with the vacuum carbs.
 
Ok thanks. You've been very helpful. As for my next purchase, do I specifically need a set of carburetors off a cb750 k6? Or are they different models I can search for?
 
76 and older are the same style of carb you just may have to rejet if you use a different year. 77 and later use a different type of carb but would still work if you got the right head to carb rubbers because they are a different size. Try to find some K6 carbs but if you can find a good deal on some earlier ones they will fit.
 
Thanks! Just bought some 76 carbs. Should be coming in on Wednesday. I hope this does the trick. Since these carbs do not come with any vacuum tubes or fuel lines, how do I find out what tubes go where when I get some? I haven't found any good diagrams that shows tubes going from what to what.
 
Put up a picture of how your carbs look when you get them so we can see wich lines are missing. Then we can tell you what goes where.
 
Alrighty! I finally got my carbs and I believe they came off a 77 cb750 because its a key top. I currently have a 1976 cb750 but with a 750 nighthawk front end. I am not sure if the cables differ from a nighthawk and 76 cb750. If so then I may have to get different throttle cables to fit the 77 cb750 carbs. Here are some pics of the carburetors and the throttle cables I currently have. There is only 1 throttle cable and 1 choke cable. The carburetors' valve flap seem to remain open which I do not understand why. Since I did not uninstall the throttle cables from a 77 carburetor, I do not know how the throttle cables go on. I really need guidance on how the cable leads go on the carbs and with the fuel lines as well. Here are some pics:
image7.jpgimage8.jpgimage9.jpgimage10.jpgimage11.jpgimage12.jpg
 
You need two throttle cabels for the throttle. The valve flaps you are referring to I am guessing you meen the choke? If so they are spring loaded to stay open until pulled closed with the choke cable. Only one fuel line on these carbs, be the one with the metal tubes between the carbs. The one with the rubber hoses is a float bowl vent.
 
So does that mean I need different right hand controls? (3 cables total including the choke?) Because I currently only have 2 cables. One cable coming from the throttle and one cable from the choke.
 
Not really. I only use a pull throttle cable, not the push one. Wich makes it possible to use most any aftermarket throttle grip. The push cable was just designed as a safety thingy when it came I believe.
The choke doesn't need to be routed up to you bars. You can put the lever for that where ever you want. I put mine just on top of my carbs (pictures in my build thread on here I believe).
BUT! If you're doing an original resto, then my advice is of no help..
 
No, I just want to get my bike running. I just don't know how to hook up the cables to the carbs. I would like pictures or diagrams of how to hook them up. I can't find it in my repair manual.
 
Thanks stabler for some sending the pic of the choke. Now I know where that should be hooked up. As for the diagrams, they show the same thing as my repair manual. They just show parts of the carburetor and the throttle but not how they hook up to one another. There is this circular disk in the middle of the carbs and I'm sure you know this because we have the same carbs. I am unsure if the throttle cable goes up and over it or down and under it or not at all.
 
The throttle cable comes over that "wheel". If you twist that wheel forward while looking in your carbs you will see the throttles in the carbs open/move upwards.
 
To me it seems like the cable has to go under the wheel to turn the wheel towards the back of the bike. If I try to put the cable over the top then when pulling the throttle cable, it would pull the wheel towards the front of the bike it wouldn't open the throttles in the carbs. With that aside, I put the carbs on and hooked up the fuel line. When I open the fuel valve and try to start my bike, a lot of fuel is leaking out of the second carburetor's float bowl overflow tube. I connected it to the one that is on the metal tube between the carbs and not the one with the pink tube. I dont believe that the carbs are suppose to be leaking this much fuel should they? Upon firing my bike up with my carburetor on and fuel leaking out of it, some electrical wiring got shorted and now I have no electrical. All I have is no electrical power and the smell of burnt wires. It just seems like one checkpoint after another. Would I need a new wire harness or try to replace the fuses? it seems like the electrical smoke fumes came from somewhere near the front end. image9.jpg
 
As far as the float bowl leaking...you have a stuck float needle. Sometimes a gentle tap on the side of the bowl with a screwdriver handle will knock the needle loose. If it doesnt then take the bowl off and free up the needle and the float. If it is free and still leaks then you will need a new needle and seat.


Better search for the burnt wire if you put a new fuse in it will just blow again. If you have smoke then you have a problem that needs to be fixed.
 
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