Bike Idles High, Tan oil, runs with idle screw disconnected

[raylanser]

So I'm at a loss form what's going on with my bike and I've done a lot of googling this week but the information I find seems contradictory, so I came here. Basic info: I have 2002 GZ250.

I made the mistake of cleaning my carb when my bike wouldn't start after winter, when the problem was really degraded gas. The bike started up after new gas was put in, but now it runs at high rpms, even when the throttle screw is completely detached. All i have to do is give it a little throttle when it starts and it immediately switches to a high idle. If the throttle screw is barely engaged it stays at high rpm, but when detached it will slowly go up and down between high and low, almost to the point of shutting off occasionally, but it doesn't quite get there. I changed the oil today because it looked cloudy and tried cleaning the carb again. The oil was a creamy tan color? I think I could smell gas in it but maybe I'm wrong. After a little running it seems like the oil is starting to cloud up again. Also the choke lever seems to have no apparent effect on engine performance. Where the choke cable connects on the carb, the part that holds the pin doesn't exactly seem to rest straight and adjusting the lever doesn't have any parent effect on the pin/needle that I can tell, but I also don't really know what is supposed to happen with it. There also doesn't appear to be any hesitation when opening the throttle.

I can drive it (it seemed to run alright the day I first got it running, but I realized as I was driving that the rams weren't going down at idle.

Anyways, I'm really just looking for some next steps in diagnosis. I don't think it's the float, since I left everything the same it ran fine before winter. I was thinking maybe the choke cable, or the accelerator diaphragm (the one on the side) looks a little worn, or maybe I didn't clean it well enough, or maybe the float somehow got changed from it's original setting?

Any thoughts would be great, thanks guys.

[b1pig]

wife's bike did this when the enricher (choke) was sticking open. i've had to replace the cable and lube it up. still have to wiggle the cable where it goes under the tank sometimes to get it to "let go" and fully close. if its hanging open, it will cause a high idle.

[Water Warrior 2]

Just couple things to keep in mind. There are 3 positions on the fuel switch. On, prime and reserve. Leave it in the on position under normal conditions. It is vacuum operated and automatically shuts/closes when the engine is turned off. And I just forgot what else I was going to say. Be right back.

Do you have a vacuum leak? There is a hose that hangs down from the air box to a position below the frame and should have a plug in the end. Remove the plug to drain air box mung and always replace the plug. The air box will draw enfiltered air and create a lean condition too. Gotta ask.....did you drill any extra air holes in the air box? Not a good idea. The GZ has a reverse flow air filter system and the box must be properly sealed. The only way to actually check for a dirty air filter is to remove it and look in the inside. Just the opposite of what we normally do when checking an air filter. Any extra holes can be covered with tape to seal them. Oh yeah. Did you get both hoses "on" on the back of the fuel switch. Make sure they are secure and are not creating a vacuum leak.

As for the oil getting cloudy I have no idea. Oil will normally change color as it is used. Oil in even modern FI engines will change color and they are very clean burning engines. A color change is to be expected eventually and likely sooner on a carbed engine such as the GZ.

That's all I can suggest. Don't really know much about carbs anymore. Got rid of my last carbed bike about 20 years ago and it was totally trouble free and I never gave it a thought from one year to the next. The Gz my wife had ran like a champion and we never had any issues.