Originally posted by car-wris
there is a screw on the carb that looks like it has a spring on it. Could that be the low end needle. It is on the other side of the air cleaner. Also, the needle that I have to adjust is the one that the fuel line is connected to. Thanx for the help.
The screw with the spring is the idle stop screw. If your wheels spin without touching the trigger that means one of two things. The carb is open to much during idle OR the idle is set to high. Usually its the first one. If you screw the screw counter clockwise (i beleive) and if you have the radio on push the brakes. the more you turn counter clockwise the more the screw will let the carb go back, eventually so much that when you push the brakes it will close the hole. what you want to do is adjust your idle stop screw so that there is only a 1mm opening in the barrel of the carb when the brakes are fully applied and during idle. turning the screw counter clockwise makes the screw hold the barrel while also raising the idle higher.
The needle that attaches to the fuel line is your high end needle. Clockwise will lean it out and counter-clockwise will richen it out. Just remember, leaner is faster, but makes the engine hotter which is not good. you want to keep it around 250 degrees with that engine. I once had an rs4 rtr3 and i called hpi and they told me that engine can go to 280-290, but i wouldnt do it.