Jetting problem, idle issue.

[400eXr1d3rZ]

I jetted my quad after I got my quad rebuilt, 165 main 42 pilot, I never messed with the air/fuel screw or the needle. Today I realised my quads throttle response was a bit laggy. So I took my carb off and messed with the air.fuel screw, 2 1/2 spins out, I put it back on, and my quad ran HORRIBLY, the throttle response lagged worse than it did before. I had to press the throttle slowly or it would just die. So I put it back to how it was, then it ran okay, but my idle was too low, so i TRIED to turn the idle knob to make the idle go higher, but every time I spun the knob the knob would just go back to the original place. Example: If the line was a 90 degrees, and I turned it right to 180 degrees (line would be level, flat.) it would go back to the original 90 degrees. So i kept turning and the little rubber tube thats over the cable popped off, and it looked like the actual cable disconnected, but stayed sorta in place. So I don;t know what to do, when I get home from school tommorow I will try to mess with it again. Any ideas on what to do? Also, my idle is SUPER low because I was trying to turn it left and right to see if it would work, once I went to the left, then tried to go back to the right nothing would happen, the idle wouldn't change, so it just remained a slow paced idle.

Please help.

[GPracer2500]

There's a thread in the "How To" section about finding the best setting for the fuel screw.

My idle screw eventually broke. The braided part under that black plastic "sleeve" came unraveled. Same thing might have happened to yours. Now I adjust the throttle stop screw with a small set of needle nose pliers.

[400eXr1d3rZ]

What do you mean "throttle stop screw"

Thanks for the reply :)

[GPracer2500]

Originally posted by 400eXr1d3rZ
What do you mean "throttle stop screw"

Thanks for the reply :)

The idle adjuster had two ends--one is the slotted, knurled knob that you turn to adjust the idle. The other end (which also turns as you adjust the knurled end) is what I'm calling the "throttle stop screw". A flexible steel line contained in a black plastic sleeve connects the two ends.

The throttle stop screw is what actually keeps the slide from closing all the way and that's what controls the idle speed. When that flexible cable on my carb gave up I just took it off and was left with the screw that actually contacts the throttle linkage. There's no slot or anything--only a squared off nub that I can grab with some needle nose pliers.

Hope that made sense--it's hard to describe the parts with words alone. Ya know....a picture is worth a thousand words....

[400eXr1d3rZ]

So the part of the idle cable that connects to the carb, is the other knob easy to see? Do I have to remove any parts of the carb?

[GPracer2500]

It's easy to see. Just follow the idle cable to the other end. The throttle stop screw is on the right side, sticking out from under that big black plastic cover on the side of the carb. You don't have to remove anything.

[400eXr1d3rZ]

I still can't find it, what does it looks like? I'll go take a picture in a minute of what I think it is.