new kdx 2003 Idle question.

[bikerman]

Hello everyone. I new to this site but not to bikes and I have a carb question. ..... no dont run off I ve done rejetting before and I have not seen this problem before.

I just bought a new 2003 kdx. by new i mean brand new. had 10 miles on it. still has tits on tires. no joke. Cost 1500.00. Im happy as a pig in stuff...The bike was horribly rich, coughed, spit and sputtered bad and would not clean out. Oil was dripping from tail pipe after test ride. Cranked on first kick though. Thats why and how I got the bike cheap..... :nod:


The factory jets in carb were: 160 main, pilot was 48, and needle was in middle setting. The float was approx 15 mm. measured. air screw setting was 1 3/4 out . just for your reference. Forgot to look at needle jet.... sorry. Has 1174 needle. Plug was a BR7ES. Not BR8ES as manual states.

I changed the main to 152, pilot to 42, ( I am ordering a 1173 needle). i moved the needle to the top clip. I left the factory air screw 1 3/4 out. I installed a new plug, BR7ES, gapped at 30 thou. The guy used Motal oil in bike at 50 : 1. I changed to Kawasaki Racing oil at 32 : 1 for rejetting purposes with real hi test 95 octain gas. no ethenol. Bike runs great now, but I have a problem I've never encountered.

My question is that when i removed the carb to change jets, the carb was really clean on the inside. I cleaned it anyway, and made the jetting modifications, but the idle screw doesnt work. I cannot change the idle speed on the bike. All in or all out no change in idle speed. Thank goodness it idles fine. It does idle a little low. With the engine hot it wants to die. Why will the idle screw not work?......an inquiring mind wants to know.....is this a trait of the carb? or have i over looked something?.The idle screw is plastic. It is not broken off or bent in anyway. Any help would be appreciated. Thanks, Bill.

 

[sr5bidder]

mine is plastic thank God I never had to do adjustments on it because it is only partly there and mostly gone, I had thought of finging one made of metal, I'd say there is no or not enough tip left on the screw to change the adjustment

Have a look down the slide hole next time you got the carb apart and see if it is sticking out at all

 

[bikerman]

I changed the jetting to : main 152, pilot 42, needle to top clip. plug looks perfect and now it idles.....and when you adjust idle screw it changes the idle....still dont know why it happened. oh well.

 

[Dirtdame]

Do you have any free play in the throttle tube? You should be able to pull the throttle open and then close it. When it closes, there should be a bit of freeplay in the throttle and also you should be able to hear the carburetor slide make a faint click as it stops on the idle screw tip. You might also want to check the idle screw and see if the tip is damaged or missing. I don't know why it would be, but you might want to check anyway....or if there is damage to the slide that would cause a problem. That screw physically lifts the slide as you turn it in, so this seems like a very weird problem.