Bike is suddenly Idling to Low!!!

Hey guys,

I just wanted to start by thinking you guys for helping me out a few months ago with my bike. It has been getting me to work and back everyday. I have been meaning to put update my threads and put pics but I have been having computer issues.

So to my bike it's an '82 KZ 550 A3 and thanks to you guys it has been running great until yesterday. On my way home from would't idle and stay running at stops. I had to reach down at a light and adjust the idle. I made it home and haven't had a chance to mess with it until now.

What do you guys think might could caused the sudden drop? Do I perhaps have a vacuum problem? I suppose somebody could have been goofing with me but not likely. Any suggestions on how you guys might proceed? I know I have already adjusted it, but I cant explain why it changed. Any help would as always would be greatly appreciated.

Thanks,
Mean

plugged fuel filter might be a good place to start with

Would assure valve clearances are within specs.
And perform compression test.

Check oil level and assure no fuel contamination.

Might also be low battery or weak ignition.

Good Fortune!

How's it idling now?

Is it now combusting on all four cylinders? Maybe it "dropped a cylinder" on the way home?

Might just need new spark plugs.

Good Fortune!

Would not suspect a vacuum problem, because air leak usually causes a "racing" idle.

Good Fortune!

Checked the mechanical ignition advancer? It should be on the right side of the engine under a cover. It uses weights and springs to advance/retard the ignition depending on rpm's.

To test it,remove the cover and give it a slight twist by hand with the engine off, it should return to it's original position.

If it's sticking or has a broken of loose spring, it could affect the idle. Some light oil for sewing machines or 3-in-one is what I use on mine for lubrication.