When you make the adjustment, you are just taking up slack in the cable. If you touch your thumb throttle, without starting it, there is probably a little play in it. If there is no play in it, then yes it will idle really high(like your pushing the throttle). But I haven't had that problem on the 4 quads I have done. I think if you go do yours, neither will you. And if you have trouble , just ask.
2000 400ex 11:1 Wiseco,stage 2 Hotcam, WB R4 full exhaust,WB rev box, K&N/OW, 450r carb, no lid, +2 a-arms,Works shocks,GForce axle,chrome stem,fat bars,250r hood, brake blockoff, ASV clutch lever, race cut fender.
2003 Cr250 White plastics, V Force 3 reed cage.