Random shutoff at idle

I have a 77 kz1000. The bike has been running great since I did the liner kit for the tank due to debris. But I will be riding the bike and when I come to a light it will drop in rpm and start to die unles I give a blip of gas on he throttle. It will only do this sometimes, I just don't understand why it doesnt do it all the time. Also it wil..... I don't know if it's knocking or what its a weird noise but it runs good at high speeds no knocking noise only when it's about to die out.

Any answers? Much appreciated

Fresh sparkplugs? Checked compresion? Stock ignition & coils? The sparkplug caps have a 5000 ohm resistor that can fail/become intermittent. If it were me, I'd get new sparkplug caps, and before installing them, cut back about 1/4" of the sparkplug wires.

If not already done, would assure valve clearances are within specs.
And this is important to do regardless of compression test results which might be peachy-keen.

Good Fortune!

How old is the battery?

What are the normal rpm's you have it set at. Does it do it all times when idling or just after you have been riding it. Could be some debris left in the idle circuits. A tank of Seafoam might help too.

Sounds like a vacume leak

Could be the glue that was used to put the handlebar grips on.

Just kidding. The knocking you hear sounds like when the engine is running with carbs that are out of synch. At really low engine speeds this is most pronounced. Why are they out of synch? Well...
Best to go through everything to ensure you are starting from a good baseline.
Make sure your carbs don't have any vacuum leaks, make sure your fuel filters are clean, pull your float bowls and make sure they are clean, etc. Drop your petcock (that just sounds weird) and clean out the screen. Pull your plugs and check them. Synch the carbs. You know, give it a good going over, maybe even a full tune up.

Take out your carbs and locate your pilot jets (usually in the float bowl) and make sure they don't have any debris in them.

Maybe crud getting into a pilot jet. Have inline filters?

I have taken the carbs apart 15 times because they kept pouring gas out of the overflow due to shit in the tank. After I put a tank liner everything stopped leaking so that was good. The carbs are so clean you could eat off of them. I don't understand how you mean synch the carbs? Is the knocking noise from the carbs or the motor because I don't hear it unless I'm not idling or low low idle about to die. Is this problem going to ruin my bike if I don't get fixed immediately because it runs fine otherwise?

Most all these bikes will emit the death rattle just before dying from too low rpm. Sounds like the engine is "digesting nails."

Even with otherwise perfect carbs, receiving adequate delivery of clean fresh gasoline -- a good strong steady idle at 1000~1200 rpm usually requires close carb sync and finely tuned pilot mixture adjustments.

Even with otherwise perfect carbs, receiving adequate delivery of clean fresh gasoline -- Noisy rough idle at 1000~1200 rpm is often attributable to poor carb sync and/or improperly tuned pilot mixtures.

When each cylinder is operating at a different level of efficiency at idle rpm, the unequal power strokes result in herky-jerky cam chain activity (which is noisy) and generally rough unsteady idle.

Carb sync, together with pilot circuit tuning, serve to equalize the power output of each cylinder at idle rpm, which contributes to a smoother running engine, especially at lower rpm.

Good Fortune!

check fuel levels in bowls with clear tube. If it's off even a little, it won't idle right.

On mine, rough idle was from timing advancer screwing up.