Motorcycle often called a bike, motorbike, or cycle is a two or three wheeled motor vehicle. Motorcycle design varies greatly to suit a range of different purposes: long distance travel, commuting, cruising, sport including racing, and off-road riding. Motorcycling is riding a motorcycle and related social activity such as joining a club and attending motorcycle rallies. Street bikes include cruisers, sport bikes, scooters and mopeds, and many other types. Off road motorcycles include many types designed for dirt oriented racing classes such as motocross and are not street legal in most areas. Dual purpose machines like the dual sport style are made to go off-road but include features to make them legal and comfortable on the street as well. Each configuration offers either specialized advantage or broad capability, and each design creates a different riding posture.There are three major types of bikes, off road, and dual purpose. Within these types, there are many sub-types of motorcycles for different purposes. There is often a racing counterpart to each type, such as road racing and street bikes, or motocross and dirt bikes.Before we expand on motocross modification, you should first know a little about the traditional motorcycle. The motorcycle is a two wheeled, single track motor vehicle. It is one of the most affordable forms of motorized transportation in the world. The bike is typically mass produced in a factory and has a standard steel or aluminum frame with forks holding the front wheel. It contains an engine and a whole array of parts such as brakes, fenders, and transmission and exhaust systems.Motocross and Super cross represent the biggest and most popular of all the racing events. Similarities exist but the two are quite different. Both racing series invite the top professional athletes in racing. Both series feature jumps, insane tight turns and a whole lot of dirt. The difference lies in how each course is created. Such bikes once called scramblers are raced on short, closed off-road tracks with a variety of obstacles. The motorcycles have a small fuel tank for lightness and compactness. Long-travel suspension allows riders to take jumps at high speed. Motocross engines are usually single-cylinder 2 stroke or 4 stroke units, which vary in size from 50cc up to about 650 cc. Motocross side car outfits have bigger engines, usually four stroke and often twin cylinder. Motocross bikes are also used in motocross.