A two-cylinder engine configuration in which both cylinders are mounted side-by-side and across the frame.
To be going slower than conditions allow through a turn. “As I was coming up to turn three this guy just parked it in front of me.”
The fuel valve, usually found on the side of the gas tank.
A small cushion designed for carrying a passenger mounted behind a solo saddle. Also, can refer to the passenger.
A small gear
To go full throttle: Reference to pinning the tachometer and/or the speedometer needle all the way to the right of the gauge. “Coming out of the last corner, I just pinned it and won.”
A large sign a mechanic writes on and shows to his rider as he goes past. Pit board signs can be used to show a rider’s position, how far he’s ahead or behind, to encourage him or even to remind him to breathe.
The lane on the inside of the track, usually adjacent to the main straight, where riders come in to have quick work or tire changes on their motorcycles.
Where the racing teams park their trucks and set up makeshift garages to work on the bikes and house the riders.
A gear system that consists of one or more outer gears (or planet gears), rotating about a central gear (or sun gear). Planet gears are often mounted on a movable arm or carrier which also may rotate relative to the sun gear. Additionally, epicyclic gearing systems may incorporate the use of an outer ring gear which meshes with the planet gears. Planetary gear systems are used in automatic transmissions. Also known as epicyclic gearing.
In the 1930’s the “plunger” motorcycle frame suspension began to replace the rigid frames of earlier bikes. This was designed so the rear axle would move up and down two vertical posts to absorb road bumps. (Later replaced by the swingarm suspension).
A condition suffered by male or female when they can’t ride their motorcycle due to bad weather.
The victory stand where riders placing first through third stand to receive their trophies.
Opening into an engine cylinder.
In two-stroke engines the critical moment when ports are covered or uncovered by the piston. Port timing can be modified to enhance a 2-stroke’s power and RPM range.
Sheet steel made into curved sections by press forming. It is often used in the construction of motorcycle frames.
An early motorcycle engine architecture where the engine and gearbox are built as independent casings, with their own oil reservoirs. (Compare unit construction).
The system of transferring power from the motorcycle engine to the gearbox. Usually achieved by chain or gear.
Motorcycle racers who do not have the backing of a manufacturer.
Knee skids, attached to leathers with hook and loop material, that riders wear to slide their knees through the turns. The riders use their knee skids to judge their angle of lean, and sometimes hold up the motorcycle if it begins to wash out from under them.
Metal rod used to open and close valves, most often from camshaft to rocker arm, on OHV engines.
