TOPIC:

I finally got the carbs installed on the 1980 KZ550 that I have rebuilt and started the bike and it finally ran and I got it to idle. I was thrilled and cranked the throttle however it was sluggish and I noticed that cylinders 1 & 2 are not firing while 3 & 4 are firing. The 3 & 4 right exhaust pipes get hot the 1 & 2 left side do not.
Cylinders 1 & 2 have good compression 125 and 130, and are getting spark. When I rebuilt it I put in new coils, new ignition kit, new spark plugs, new plug wires. I also checked the valve clearances and replaced shims so that all the clearances were according to spec.
I soaked and cleaned the carbs, took the float bowls off, soldered cracks in 2 of the overflow tubes, cleaned the pilot and main jets, the float valve seat and float valve needle, and set the float levels on the bench and on the bike when I finally got them installed.
It looks to me like the 1 & 2 cylinders are not getting fuel so I must have missed something when I cleaned the carbs. My next step is to take the carbs off and try to figure out what I missed cleaning or might need to replace.
I would appreciate getting any opinions, or comments or help trying to figure out my problem.
This is a picture of the spark plugs 1 & 2 are black 3 & 4 are white.



Tomas Douglas

Are you sure you have the plug wires on the right plugs?

Yes right coil wires to 1 & 4, left coil wires to 2 & 3.
Tomas

Got the correct hose connected to the fuel shut off valve?

did 1 and 2 fire prior? How is your fuel delivery? You could try the clear tube test with the carbs on the bike to insure your bowls are filling up from the petcock and fuel inlet lines.

Idle mixture screw are all equal?

Check the common vent between the two carbs.
Steve
kzrider.com/forum/3-carburetor/597187-critters#661716

Take the float bowl screws out on the carbs of those cylinders not firing to check you are getting fuel into those carbs. perhaps the floats are stuck closed or something is blocking the transfer of fuel to the carbs on the cylinders that are not firing.

Petcock strainer too.
Steve

This is a picture of the mower tank that I used when I bench tested float levels, I used the same set up after installing the carbs on the bike and the bowls were all getting gas.

No this is the first time I have started the bike I am at the final stage of the rebuild. I am using a mower tank on a stand for fuel see the picture below. All the carbs are getting fuel but it isn't getting into the 1 & 2 cylinders.

If you can start the bike, or even if you can only crank it with the starter, when you put your hand over the intake throat of # 1 and #2 can you feel vacuum? Ed