Hi
Could some one give me some idea of where the balance screws are on a CB1 400 N Reg as my mate has asked me to balance his carbs. Also any pointers as im use to the GSXR400.
Thanks
Ric
Carb Balancing
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Re: Carb Balancing
I'd like to know the answer to this question too. Just to get the discussion started, here is a photo of the CB400 Super Four 92-95 carbs.

We're looking at the exit of the carbs that connects to the engine.
I assume the carb balancing screws are indicated by the arrows.
The carb balancing rubbers connect just below the exits, after removing the screws.
Please correct if I am wrong.

We're looking at the exit of the carbs that connects to the engine.
I assume the carb balancing screws are indicated by the arrows.
The carb balancing rubbers connect just below the exits, after removing the screws.
Please correct if I am wrong.
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Re: Carb Balancing
That's a big help thanks
what do I do about the air filter ?? I will have to remove this to get to the carbs and i know on my GSXR400 having the air filter out makes a difference to the readings on the carbs.
can anyone give me some advise?
Ric
what do I do about the air filter ?? I will have to remove this to get to the carbs and i know on my GSXR400 having the air filter out makes a difference to the readings on the carbs.
can anyone give me some advise?
Ric
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Re: Carb Balancing
I'm not sure you should do carb balancing without the air filter. I would leave it back in. I would leave the tank off and replace it with a small fuel container and tab. Refer to your manual or the Haynes Motorcycle Mechanics book for the correct procedure of carb balancing. Of course make sure that the carbs are clean before you start and that the float chamber has the correct fuel level.
Hopefully Aaron has more tips
Hopefully Aaron has more tips
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Re: Carb Balancing
I will have a look to see if i can get to the screws with the air filter on it's just thats i though from memory that the air filter was in the way.
Thanks
everyone for all your help.
Ric
Thanks
everyone for all your help.
Ric
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Re: Carb Balancing
I will have a look to see if i can get to the screws with the air filter on it's just thats i though from memory that the air filter was in the way.
Thanks
everyone for all your help.
Ric
Thanks
everyone for all your help.
Ric
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Re: Carb Balancing
I had a look last night at my mates Carbs and i found the balance screws same place as my GIXER but i cant find where to connect the carb balanace hoses could someone explain where they are???
PS The Carbs pictured above are slightly different to the ones on my mates bike the tops on his are metal and the mixture screws are at a side ways angle if this helps anyone.
Ric
PS The Carbs pictured above are slightly different to the ones on my mates bike the tops on his are metal and the mixture screws are at a side ways angle if this helps anyone.
Ric
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Re: Carb Balancing
I know this answer is probably far too late for your query, but having just balanced my super four, I thought I'd post the answer up for reference.
the ports to connect the vacumn gauges to are as below:
cylinder 1 - this is simply the vacumn line that connects to the fuel tap. Just remove the vacumn line, and replace with the gauges tube.
cylinder 4 - this is exactly opposite to the above - look at the cylinder head from the right hand side of the bike, and you'll see a screw recessed between the fins of the cyclinder head. This screw covers the port.
cylinder 2 - the photo below shows this screw - it's silver, with a washer, and is very near the centre of the pic. its screwed into the lower part of the cylinder 2 inlet manifold, close to the cyliner block

cylinder 3 - like cylinder 2, but again on the opposite side. So the port is in the right side of cylinder 3's inlet manifold.
Removing these 3 screws was very tricky, so good luck. I destroyed them all in the removal process, and have replaced 2 & 3 with nice little hex bolts, which are much easier to remove. A socket won't fit onto cylinder 4, so I had to get a new machined screw.
hth
Ian
the ports to connect the vacumn gauges to are as below:
cylinder 1 - this is simply the vacumn line that connects to the fuel tap. Just remove the vacumn line, and replace with the gauges tube.
cylinder 4 - this is exactly opposite to the above - look at the cylinder head from the right hand side of the bike, and you'll see a screw recessed between the fins of the cyclinder head. This screw covers the port.
cylinder 2 - the photo below shows this screw - it's silver, with a washer, and is very near the centre of the pic. its screwed into the lower part of the cylinder 2 inlet manifold, close to the cyliner block

cylinder 3 - like cylinder 2, but again on the opposite side. So the port is in the right side of cylinder 3's inlet manifold.
Removing these 3 screws was very tricky, so good luck. I destroyed them all in the removal process, and have replaced 2 & 3 with nice little hex bolts, which are much easier to remove. A socket won't fit onto cylinder 4, so I had to get a new machined screw.
hth
Ian