[fredj]

I have a 2004 Bayou 250 with a weird problem. Starts right up and idles nicely. Will continue idling nice and slow. A quick spirt on the throttle (without letting it rev up) and it comes back to slow idle. When I rev it up to about 2500 rpm it stays revved at about 1800 rpm. Now, get this, if I turn it off and restart WITHOUT TOUCHING THROTTLE it starts right up and idles nice and slow. (This rules out cable adjustments etc which I have checked anyway) Idle adjustment screw on side of carb is all the way out. (I know this isn't right either) I have re-adjusted the pilot screw at the bottom of the carb a bunch of times and it affects the slow idle but does nothing for the high 1800 rpm idle. Any ideas?

 

[RCW]

There is a small part called a starter plunger (enriching choke valve to us old timers) that sticks from misadjustment or dirt. This is the most common cause of this particular problem. The next thing to check is the throttle slide valve and make sure the needle is properly retained by the circlip, if it is free to slide inside the throttle slide this same symptom will also occur.

Also check your throttle cable to be sure it is free and not binding.

What I would do is pull out my repair manual and then take the carb apart and clean everything, then double check the adjustments, cable boot seals, etc. You almost never need any new parts when you do this, but do not use carb cleaner until after it is fully disassembled and then do not spray it on any plastic or gasket. I just use light machine oil that is intended for musical instruments and then carb cleaner only on the tube and various carb body holes if there is evidence of gum after I clean everything with light oil. Most often the carb cleaner is not even needed, and it raises cain with all the fiber and plastics it comes in contact with.

 

[fredj]

Thanks. I'm going to try to find the starter plunger. Looked in my Genuine Kawasaki manual and it does mention this in the carb disassembly instructions but fails to show where it is on any diagram.

 

[RCW]

The plunger is right down on the carb body next to the casting for the throttle slide. It is the second cable on most carbs. Some use a lever to trip the enrichment valve, but I believe these Kaws all use a cable.