If you want to give your bike some extra power, you are going to want to fit a new carburettor. You can pick up a decent carb fairly cheaply (for around $60). For an even greater boost in power, you will probably want to install a free flow air filter, this will derestrict the airflow and give you extra horsepower.

Another trick that some people use is to advance the timing. Basically, after the fuel is ignited, some time elapses before the expanding gases push the piston down. Advancing the timing causes the fuel mixture to ignite sooner, giving you a power boost. 

Other popular modifications include porting the manifold, removing the spark arrester screen, increasing the compression ratio, removal of the choke, opening up the air intake and removal of the flywheel cover.

Of course, for the serious enthusiast, it is enough to get the bike performing at the top of its capabilities, however for some people, looks are important too. In recent years, these bikes have become flashier with people installing motorbike decals on their machines. These stickers can be found in numerous places and can be ordered online from many websites. 

Before attaching your graphics, you need to ensure that the area you are installing them is clean and free from any major scratches. If you are replacing existing stickers, you will need to remove these first, which can be done easily using a hair dryer. Once you have removed the existing stickers and cleaned the surface, you will need your hair dryer again to warm up the plastic that you will be applying the graphics too. Apply your sticker a little at a time, making sure that no bubbles form as you lay it down. If there are any bubbles that you can’t squeeze out, simply prick them with a needle to let the air out and flatten them down.

As you can see, there is a lot that can be done to your pit bike to modify it’s look and performance. If you are not sure of what you are doing, it is worthwhile finding someone in the know to help you. A lot of these modifications are irreversible and can cost you a lot of money and grief if done wrong.