Tic
Simple motor tics are typically sudden, brief, meaningless movements that usually involve only one group of muscles, such as eye blinking, head jerking, or shoulder shrugging. Motor tics can be of an endless variety and may include such movements as hand clapping, neck stretching, mouth movements, head, arm or leg jerks, and facial grimacing.
Motorcycle speedway
Speedway uses a unique type of motorcycle, governed by the FIM's "Track Racing Technical Rules". In the past, bikes with upright engines were used (the name taken from the way the engine sits in the frame), but today most professional riders use laydown bikes as it is argued that they are easier to handle. As speedway bikes do not use brakes, the clutch is used as a release mechanism at the start of races. FIM regulations state that the motorcycles must have no brakes, are fueled by pure methanol, use only one gear and weigh a minimum of . By using engine and rear wheel sprockets the gear ratio can be adjusted as required for track conditions. The use of methanol allows for an increased compression ratio to the engine producing more power than other fuels and resulting in higher speeds (approximately when cornering).
Machines used must: