Plug chops are a way to isolate each major throttle position's mixture setting, by isolating the jets which control the mixture in those throttle positions. With these types of carburetors, you can be lean in one throttle position, and be rich in another. This process allows you to tune each throttle range and the corresponding jets.The process is like this.Put a piece of tape or other indicator pointer on your throttle housing, like an arrow pointer.Put a piece of tape wrapped around your throttle grip. Then use a magic marker on the tape to mark the 1/4, 1/2, 3/4, and Full throttle position, so that they correspond with the pointer when you are at these throttle positions.Use a new plug.Then, take the bike out and ride at one of these throttle positions for a few minutes so that the plug can get enough time to get its color. Hold it at that throttle position the whole time without changing it, so that it isolates that throttle position only. When you get to a safe place to pull over to check the plug, cut the engine and pull in the clutch, don't change the throttle position until the engine stops, and coast to a stop on the side of the road and check your plug for color.If the color is a medium tan, or something around that, it's pretty good for that throttle position, and you can try the next throttle position, etc.Throttle positions and their corresponding jets are:Idle = Pilot jet and bleed screw1/8 = Throttle slide cutaway1/4 = Needle jet mostly1/2 = Needle jet and jet needle combination(they actually overlap in function from 1/4-3/4)3/4 = Jet needle mostlyFull = Main jetDoing this will give good even throttle results with proper mixture settings all thru the whole throttle range, and should eliminate any hiccups, bogs, or flat spots in the entire throttle range, and prevent lean conditions from causing engine damage, and keep your fuel economy at its best.