No low end, everything else... pretty good

Tyrell Corp wrote: I think the 3 carbs are blanked off at the intake manifold spiggot and a 4 th is piped to the vacuum fuel tap.
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On the 1978 KZ650 there is a vacuum nipple toward the top front of #2 carb which is used to provide vacuum to the petcock. That is the only vacuum line on the carbs. Each carb holder has a vacuum nipple that should have a rubber cap on tight. Those nipples are used to attach the carb sync gauges when syncing the carbs. If they are not tightly capped during normal use the engine will run like crap if it runs at all. Ed

Ed, I replaced the black vacuum line between the two carbs. This is what they had when I got them.



If they are not supposed to be attached that would explain something.

Accidentaly posted twice... teach me to try and post using my phone.

Ed, I replaced the black vacuum time line between. This is what they had when I got them.

If they are not supposed to be attached that would explain something.

That looks like a vent for the float bowels.
Steve

Black tube between carbs is the it should be.
What size pilot jet u installed?

I'm pretty sure I figured it out. 3 of my carbs were synching up perfectly and one just wouldn't go anywhere above 6cm Hg. I decided to check compression on that cylinder and low and belgold it was at 80psi. So how hard is it to change out rings?

Check the valve clearances first. That's still run-able barely. Plugs again? Still, if there is a running issue, it could effect the compression. Corrected, it could come back up. At least you have one cylinder to check on.
Steve

I ordered new valve cover gaskets as well as those half-round stoppers as I am leaking oil from that area. I might as well check valve clearances next week before ripping out the motor and tearing it down. Thanks for the suggestion.

Thanks for the picture. That's not a vacuum line. The #2 carb and the #4 carb have vent nipples. One of them is shown in your picture as the brass fitting. The #1 carb and #3 carb do not have the vent nipples. Instead, the #1 carb has a tube that connects to #2 and the #3 carb has a tube that runs to the #4 carb. The vents on #2 and #4 then vent #1 and #3 carb through those vents. Ed

ewolpert wrote: I ordered new valve cover gaskets as well as those half-round stoppers as I am leaking oil from that area. I might as well check valve clearances next week before ripping out the motor and tearing it down. Thanks for the suggestion.

You don't have to tear out the motor to do the top end.
Steve