idle screw?

Got questions? We got answers....
Post Reply
ckelly33
Member
Posts: 10
Joined: 10:42 am Apr 27 2015
Country:

idle screw?

Post by ckelly33 »

The 93 kdx 250 has two screws one that is closer to the float bowl and gold and then there is a silver one with a spring around it closer to the top which is idle? Is one of them the air/fuel mixture screw? Neither seem to make a difference when adjusted.
User avatar
Julien D
KDXRider.net
KDXRider.net
Posts: 5858
Joined: 07:53 pm Nov 07 2008
Country: USA
Contact:

Re: idle screw?

Post by Julien D »

The one with a visible spring is the idle. The smaller screw you see is the air/fuel mixture. If neither make a difference then your low speed circuit / pilot jet is probably gummed up.
Image
ckelly33
Member
Posts: 10
Joined: 10:42 am Apr 27 2015
Country:

Re: idle screw?

Post by ckelly33 »

I took the carb off and took it apart and cleaned it with a carb and throttle body cleaner. I also cleaned my filter. Put all of it back on the bike and it ran but was still not idling without the throttle and dies after a few minutes of riding. So I then re evaluated the carb and checked the reed valve and it all seemed to be alright. Only thing else that was wrong was it was blowing oil out the head pipe because of the worn out o'rings. I tried as best as I could to reseal it but the bike won't start now. Any ideas?
User avatar
KDXohio
Supporting Member
Posts: 825
Joined: 06:04 pm Jun 19 2013
Country: United States
Location: Dayton, Ohio

Re: idle screw?

Post by KDXohio »

probably fowled the plug try a new spark plug
1990 KDX200 FMF Fatty, Answer VFC silencer, VForce 3 Cage, Wiseco Piston, KX125-J series KYB USD fork conversion, Race tech goldvalves, J series front brake assembly, air-box snorkel removed, Acerbis Headlight, KX450F Front fender, Pro Taper RM bend bars, ASV front Brake lever, MSR Clutch perch and lever, RB Head mod, 36mm PWK carb, Trail Tech Kickstand.
royadams
Supporting Member I
Supporting Member I
Posts: 567
Joined: 10:38 am Aug 20 2012
Country:
Location: anderson sc

Re: idle screw?

Post by royadams »

If it has stock jetting its way to rich. If the pilot circuit is way rich the air screw will have very little effect. I ran 32 155 #7 slide and two sizes leaner on the needle and a br7es plug .most run a slightly richer pilot jet.I also had to change the jet block gasket in the carb.
ckelly33
Member
Posts: 10
Joined: 10:42 am Apr 27 2015
Country:

Re: idle screw?

Post by ckelly33 »

Could that prevent it from running?
User avatar
KDXohio
Supporting Member
Posts: 825
Joined: 06:04 pm Jun 19 2013
Country: United States
Location: Dayton, Ohio

Re: idle screw?

Post by KDXohio »

Yes too much fuel while starting can foul the plug causing it not to start
1990 KDX200 FMF Fatty, Answer VFC silencer, VForce 3 Cage, Wiseco Piston, KX125-J series KYB USD fork conversion, Race tech goldvalves, J series front brake assembly, air-box snorkel removed, Acerbis Headlight, KX450F Front fender, Pro Taper RM bend bars, ASV front Brake lever, MSR Clutch perch and lever, RB Head mod, 36mm PWK carb, Trail Tech Kickstand.
ckelly33
Member
Posts: 10
Joined: 10:42 am Apr 27 2015
Country:

Re: idle screw?

Post by ckelly33 »

I have a new plug but I'm afraid it's gonna foul again. How do I fix the kdx from running so rich?
Post Reply