can't start my KZ750 after sitting for sometime

So I can't start or it is hard to start after my KZ750 was sitting for some time. Previously it started just fine now it just rotates the starter and sometime bangs in the end. Should I up the idle screw?

It might be flooding one or more carb. As you crank, the plug clears and finally pops. Same thing with bad valve seals because oil drains down and fouls the plug.... then as you crank it, the gas cleans the plug and it finally fires.

Guess how I learned about that...... :ohmy:

How long is "some time"? Hours; days; weeks; or months? Ed

Months. And when I said bangs I meant sound.

Has the weather been hot & does your fuel contain ethanol?
I would drain the carbs & maybe the fuel tank, then add fresh fuel.
Also, be sure to check the battery.

If it sat for months the carbs are probably clogged up. Gasoline leaves a nasty residue after a while. If mine, I would start by cleaning the carbs. Ed

650ed wrote: If it sat for months the carbs are probably clogged up. Gasoline leaves a nasty residue after a while. If mine, I would start by cleaning the carbs. Ed

This.

But they were fully cleaned before.

The gasoline doesn't care. If it sits around all bored, doing nothing, it will do what it wants to do.

Did you try using fresh fuel & charging the battery?

karoliens wrote: But they were fully cleaned before.

Sorry to say that it does not take the ethanol based fuel (these days) long to clog the small pathways in the carbs. Might get some Seafoam (fuel additive), pour a few ounces in with fresh fuel and see if you can get that to flow thru the carbs. Should assist, a bit, with the clean out and keep your fuel stable if it has to sit for a while.

If this doesn't work, the only other option is to get the carbs cleaned again...

edit: Oh, and drain the old fuel. You should be able to use it in your car with no ill effects...