Motorcycle speedway, usually referred to simply as speedway, is a motorcycle sport
involving four and sometimes up to six riders competing over four anti-clockwise laps of an oval circuit. The
motorcycles are specialist machines that use only one gear and have no brakes. Racing takes place on a flat oval
track usually consisting of dirt, loosely packed shale, or crushed rock. Competitors use this surface to slide
their machines sideways, powersliding or broadsiding into the bends. On the straight sections of the track, the
motorcycles reach speeds of up to 70 miles per hour (110 km/h).
At the start of a race it takes between one and two seconds for the motorcycle to reach the "curve speed", which
is roughly estimated to be the equivalent of 2.5 to 3 seconds to reach 100 kilometres per hour. The start of the
race is an important aspect of the race overall. "Gating" correctly can help a rider gain an initial advantage
over other riders but speed advantages can be made as a race progresses. Those riders willing to take a risk and
opt for finding the grippy parts of the track rather than the race line, are sometimes rewarded with extra speed
allowing them to pass other riders either on the outside or the inside.
Tracks
Tracks used for professional speedway racing are regulated by the Fédération Internationale de
Motocyclisme (FIM) who provide rules concerning construction, size and safety requirements. Speedway racing
takes place on a level oval track consisting of two straights joined by two semicircles. Tracks must be between
260 and 425 metres in length, this is measured at a distance of 1 m from the inner boundary. Tracks may be
banked, but the gradient must under no circumstances exceed 5% in the straight, 10% in the bends, and must
remain constant and grow from the inner edge to the safety fence. A white start line is marked across the track
approximately mid-way along one of the straights. The starting area is also divided into four equal parts (known
as gates) by white lines marked at right angles to the start line and extending back at least 1 m. Additional
rules govern the placement of warning systems such as lights . Races (known as heats) consist of four riders
racing over four laps from a standing start. Riders wear different coloured helmets, traditionally in team
events red and blue denote home team riders, and white and yellow/black quartered colours denote the visiting
riders.
Motorcycles
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 77 kilograms (170 lb). 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 (approx. 130 km/h). Riders must be
able to get their bikes to the start line under their own power, without any external assistance and not by
pushing the machine, then line up in parallel. In addition, all motorcycles must have a safety cut-out device
fitted. The high compression ratio of the engine can also assist in slowing down a machine; if the throttle is
closed, the engine may stop.
