Does your motorcycle have problems holding a stable idle rpm? A dirty throttle body can be the problem. The throttle body is part of the air-intake system that controls how much air enters the engine to facilitate combustion. It is usually located between the air-box and intake manifold. The main component of the throttle body is the butterfly valve that swings open when you twist the throttle grip on the handlebars.
Back in the day this valve was always linked via a throttle cable. Now, drive-by-wire systems are more common on modern motorcycles and make things a bit more complicated to fix.
So how do we clean the throttle body? First, locate the throttle body. It is between the intake manifold and the air-filter box. Use a flashlight to examine all of the connections to and from it. Carefully unhook any electrical sockets. There might be vacuum lines. Undo these, and it's not a bad idea to write down where what is going.
Separate the throttle body from the system by first carefully undoing the bolts and screws. Don't forget the clamps that are holding any hoses in place, too. Be very careful when handling the throttle body. It is a very expensive component. Now you will see it it is still clean or not.
A throttle body will get gunked up and dirty over time. Hard city use can foul up the butterfly, and chances are it won't stay open, or closed. Use a liberal amount or carburetor cleaner to melt the gunk. Use a toothbrush or rags if necessary.
Never spray carburetor cleaner on the throttle body while it is still mounted on the engine. That's a bad idea. After putting everything back, your motorcycle should idle fine. If not, there is more serious problem lurking somewhere. It's probably a good time to visit a professional mechanic. Don't worry, there's a fix for everything.