Bafflectomy: As you said. Baffles are in the silencer to, uh, silence.
AI Removal: As you said. The air injector is a valve arrangement that injects air into the exhaust stream to cause the unburned fuel to burn on the way out the header pipe, to reduce hydrocarbon pollution.
Snorkel: Soft plastic tube-like thing at the entrance to the air filter, under the left side cover. It can simply be pulled off, can also be reinstalled at will. Removal theoretically increases air flow into the filter. Theoretical disadvantage is that rain water might get into the filter.
Jet: Nozzle in the carburetor through which the gasoline passes. The size of the orifice can be changed by changing the jet. There are two jets in the carburetor, the pilot jet and the main jet.
Synchronizing: Turning an adjusting screw so that the two carburetors work well together, i.e. are synchronized.
Idle mixture screw: A carburetor adjustment only accessed with a special tool. You can get the special tool and use it to adjust, or use it to remove the stock idle mixture screws and replace them with functionally identical idle mixture screws that you can easily turn with your fingers instead of a special tool.
Needle: Another carburetor thingie--looks like a needle--that can be changed for a slightly different needle to adjust performance.
Shim: A washer used to adjust the needle height.
Igniter: Electronic ignition control unit under the seat. Sometimes replaced with an aftermarket Procom igniter.
Coil: Electric pulse generator to fire the spark plugs, under the tank. Can be replaced with an aftermarket coil.
