Done Everything, Still Has Hanging Idle

The side-located pilot ajustment screws are air screws. Typical default setting is 1.25~1.5 out from lightly seated.

Perhaps pilot mixture is too lean (resulting from screw being turned out too far counter-clockwise).

In line with otakar's suggestion, would re-set all 4 pilot air screws at say 1.0 turn out from lightly seated. Then test run for effect on idle peformance.

Then re-tune each individual pilot screw in usual manner for best low steady idle.

This screw regulates volume of air allowed into the pilot mixture. Turning in clockwise reduces air to enrich mixture. Turning out counter-clockwise allows more air for a leaner mixture.

Good Luck!

Hi Redwood, I see you had the carbs cleaned, but were all the o'rings replaced? It's posible there may be leakage through the enricher circuit. All the gaskets and o'rings should have been replaced. I was recomended to do just that, not only on KZR but KZ 650.info forums. Harbor Freight has metric o'ring sets for around $10. If your linkage is completely closed, then it has to be an internal problem in the carbs., if there are no external leaks. My KZ 650 acted very similar. Just my 2 cents worth. Good luck. Bob

The throttle crank slaps against the idle adjusting bolt when the throttle is released. Cables were lubed before I installed them, same routing as stock.

I drilled out the caps, adjusted the pilot/fuel screws already.

The o-rings we're talking about part of the enrichener circuit...I don't know if those were replaced. Are we talking about part 670 on the image, or the plunger caps as well?

Make sure that O ring 11009D has a good seal. the way to check that is to try to screw the needle in without the spring. If you do not feel the resistance of the O ring than you have a leek. Those O rings are very important.

redwood wrote:

...I drilled out the caps, adjusted the pilot/fuel screws already. The o-rings we're talking about part of the enrichener circuit...I don't know if those were replaced. Are we talking about part 670 on the image, or the plunger caps as well?....

Fwiw, kawasaki.com shows 0-ring only on version without plug (Canadian). And no 0-ring on version with plug (U.S.).

Perhaps the plug must remain to seal against outside air intrusion where there's no 0-ring (U.S.).

Just speculating.

Here's the diagram from kawasaki.com.
Part #11009D is the 0-ring.

Good Luck!

[Click on image to enhance view.]

Sometimes a small round lead fish line weight may serve as a removable plug.

Or it may be feasible to replace the non-0-ring screws with the 0-ring versions, and thereby eliminate the need for any plugs.

Good Luck!

I thought so too, but the plug is just a small piece of metal, and this bike had been doing this crap since it started running again.

Seriously, check the plugs before you pound your head into anymore brick walls. If you have a whiteish plug you need to figure out why that cylinder (or cylinders) is/are lean. If the plugs show no lean condition you can look to other causes.

If you buy a complete rebuild kit, they will come with new needles that have O rings.

Maybe the reported idle problem isn't related to air leakage at the pilot adjustment screws.

The reported idle problem might be caused by having failed to correctly perform required bench sync with idle thumb screw at mid-way position during reassembly. This leaves adjusting room needed to further lower the slides when performing final sync and fine tuning pilot air screw settings.

Where this failure occurs, subsequent attempts to sync and/or set idle are frustrated because the thumb screw runs out of adjustment before the slides can be lowered enough for proper sync and low steady idle.

Good Luck!

What Patton Said..
You may have a look at one of the carbs the body and make sure its throttle slides works as it should . They can hang. I have found that about 1 out of 50 sets of carburetors I rebuild just won't work right after messing with them. It takes me over a day to do a set .

Ok cool. I'll ask him if he replaced the o-rings, bench synched, etc. I can't imagine he didn't, since his whole garage is projects, but I guess we'll find out. Thanks for all the help!