carb problem

I have a kz650b and i just got done rebuilding the carbs. the problem i am having is that carbs one and four you can feel the suction and carbs 2 and 3 you can't and when i put my hand over 2 or 3 the engine dies, but when i put my hand close to 1&4 the engine revs up. also when i try to give it gas it dogs down. i am not sure what is wrong. 2&3 were working fine while i was riding it. can anybody help me.

How is the vacume seal between the carbs and the engine?
Test this by spraying starting fluid on the boots (the black rubber mounts for the carbs seated to the engine)and listen for engine changes in rpm. If there are holes in the boots, then the starting fluid will get sucked into the engine and change the rpms. That is an indication of a bad boot that is allowing air in at a place where it should not be happening.

How did you synch the carbs when you reassembled them?
There is a possibility that some of the carbs are opened farther that the others. This needs to be as close as you can get it. I used a piece of coat hanger wire to measure the height of each of the slider barrels in the throats of the carbs.

Are they Mikunis?
Just curious.

Check for vacume leaks between the carbs and the engine,
then check the throttle barrel heights,
then come back and re-post.

There is still a chance that the finicky old carbs are still gummed up.

Have to ask, have you re-built carbs before?
What tools did you use to clean it out? (I used a coffee can and can of carb cleaner)
Did you have access to compressed air?

Hope you find the snafu soon,

Oh and welcome to the site.

Q

Sounds like 2 & 3 are not firing. Check for fuel in the float bowls of the 2 & 3 carburetors and if there is fuel, you may have an ignition issue.

they are minkuni, this is my first time rebuilding. but I have the machanics book on the bike and followed it step by step.

I checked the boot s and they are still good. and i used a wire tool that was recemended to sync the carbs.i also have the vacum sync tool as well. did you sync them with the idle screw all the way out or in.

i baught the gunk carb and parts cleaner and carburator clean and yes i used my air compressor to clean out the carb cleaner

but like i said all four carbs were working fine till i was like not even 1 mile from my house and now the 2&3 don't work .also my bike is having trouble staying running at low rpm idle and shuts off.

wiredgeorge i will check on that and get back to you

Now that I think of it, you may some internal clogging on 2 & 3... it may also be ignition. Check to see if there is gas in the bowls first.

I have check the bowls and all four had fuel in them. i checked to see if i was getting spark to all four plugs and i am. the bike will start up but will not stay running unless i turn the throtle adjustment screw in to where it is idling at 3grand. # 2&3 carbs still do the same thing when i put my hand close to them the engine dies.

could my air fuel mix bre to rich for the engine to stay running.