A typical modern bicycle is a bicycle classic two-wheel. Framework bicycle shall be ordinary steel or alloy, aluminum or composite. The chassis is a bicycle wheel (usually) and spoke with pneumatic tires. The drive is transmitted by the drive system of the bicycle, which is usually a chain transmission and gear changes the system (external derailleur, shifting the chain on the sprocket teeth of different quantities or internal, located in the hub). There are also models of the cardan shaft drive transmits. Brake: foot may be operating in the shooting pedal back (so-called torpedo or brakes integrated into the inner derailleur). The most popular are acting on the rim, however, mechanical, or (rarely) hydraulic brakes, manual (lock jaw, brakes V-brake). Increasingly popular for bicycles are disc brakes. Now often (except bicycles road bikes) is used in bicycle amortization front and rear wheels.