I have 1998 r1 and it's high reving on idle

SOURCE: bike idles, but with a little throttle it jumps to high rev and wont come back down to idle

You need to oil your cables first....They make a gadget to help you do this...it clamps around the end of the cable, and you spray oil into a provided hole for a spray nozzle tube...Then see if the cables are unstuck by turning the throttle grip back and forth for awhile....start it and see if that helped....if not you may need to replace the cable(s)...I doubt that the slide in the carb is hanging up...or valve.If this doesn't work notify me.

SOURCE: Yamaha DT 125 1986 - High Revs when idling

There have an air leak between the carb and the cylinder and/or the head and cylinder. Old hard / cracked rubber fittings and O rings are usually the problem. When extra air gets into the system it leans the fuel mix and the high idle is the result. It also means the engine runs hotter. Also, cracked or broken reeds can be a source.

SOURCE: High revving

annoying problem isn't it! make sure the air/fuel mixture screw is set properly. generally start about 2 turns out then just turn it about a quarter turn at a time untill u find the right spot. (my '07 likes it at 2.5 turns out) good luck and also you may have to readjust the idle screw when you move the air screw.

SOURCE: its a 1980 yz465,runs great

You may have an intake leak between the carb and head. Make sure the carburetor is fully seated in the intake boot and that the intake boot has no cracks in it. If the carburetor is a flange type, make sure that the gasket or "O" ring, (whichever is used), is in good shape. You can test for a vacuum leak by spraying WD-40 around the carburetor mount. If the engine changes speed, you have a leak. Running the engine with an intake leak can cause serious engine damage.

SOURCE: 2001 vmax My throttle has alot

Try lubing your cables and throttle mechanism first. Do your adjustment when the bike is warm. It sounds like you're making one of the cables too tight.