A B C D E F G H I J K L M N O P Q R S T U V W X Y Z


Nac-nac: A freestyle trick in which the rider brings one leg over the seat and then puts his foot back on the peg for the landing.

Needle:  Is a shaft with a pointed end. When the needle is fully seated in the seat, no gasoline can enter the float bowl. As the needle is lifted off the seat some gas pours  into the float bowl. The needle moves when the float in the float bowl drops below a set height.

Needle Bearing: A roller type bearing in which the many rollers have a very narrow diameter  in relation to their length. The design makes them particularly useful in situations where there is limited space such as the rod bearings on some pistons. Also called "Quill-type bearing."

Nipple: Small metal part of the wheel that connects the spoke to the rim.

No footed can-can: A freestyle trick in which the rider puts both of his feet on one side of the bike and straightens his legs horizontally, and then puts his feet back on the pegs for the landing.

No Handed Landing: A freestyle trick in which a rider takes both of his hands off the bars and lands the bike with them still off.

No hander: A freestyle trick in which the rider takes both hands off of the bike and then replaces them for the landing.

Nose: Term used when a rider jumps a ramp and lands on the front wheel first.

Nothing: A freestyle trick in which the rider takes his hands and feet off of the bike and then replaces them for the landing.

Novice:An amateur skill level of racing just after beginner. Beginner, Novice, Intermediate, Expert

Off Camber: A turn where the outside of the curve is sloped downward.

Oil: A substance that lubricates and cools the moving parts of the engine and reduces the formation of rust and corrosion. It contains additives which fights the corrosion of bearings, keeps small particles in suspension, reduces engine wear, and reduces oxidization, minimizes carbon, lacquer, and gum formation. Oil comes in varying viscosity weights suitable for efficient operation in cold and hot weather and for engines in varying states of wear.

Oil Drain Bolt: Bolt that is removed to drain oil located on the bottom of the transmission.

On the pipe: When a rider or bike is going very fast. This expression refers to when a dirt bike's two-stroke engine is operating at optimum rpm. Exhaust pipes for these motorcycles are designed to work best at certain engine speeds. When a motorcycle is on the pipe, it is running at the rpm that gives maximum horsepower.

One hander: Freestyle trick where rider takes one hand off of the handlebars and then replaces it for the landing.

Outdoor: Refers to races held outside in the elements.

Over 25: A class of racing for people over 25 years old. 

Over30: A class of racing for people over 30 years old.

Over40: A class of racing for people over 40 years old.

Over50: A class of racing for people over 50 years old.

Over60: A class of racing for people over 60 years old.

Paddle Tire: Tire that is used for riding in the sand.

Panic rev: The typical reaction when a frightened rider sees that his front end is low in the air. Can sometimes bring the front end up. If you hear this at the track, look quick cause you'll probably see a crash!

Parade lap: Typically done by pros at larger events. The winner of the race takes an extra lap around the track for the fan's entertainment.

Peewee: A 50cc dirt bike, also a class of racing.

Petcock: A small valve or tap which is used to control the flow of liquid. A petcock may also be found on the line coming from the fuel tank.

Petroleum: See Petroleum Oil.

Petroleum oil: Raw material from which gasoline, kerosene, lubricating oils, propane, diesel fuel, etc. are refined. Consists primarily of hydrogen and carbon; but also contains other elements. Its source is decomposed organic matter which has been buried.

Pile up: A single crash in which multiple bikes are involved.

Pilot Jet: Metal piece located inside the carburetor used to mix air and fuel.

Pinned: Term referring to a bike that is at its maximum RPM.

Pipe: Part of the exhaust system connected to the cylinder and the silencer. Transfers exhaust from the cylinder to the silencer. Also known as the exhaust pipe.

Pipe Hanger: Metal piece that connects the exhaust pipe to the frame of the dirtbike to stabilize it.

Piston: Metal piece located in the cylinder. Connected to the rod and the ring. Used to support the ring and create compression in the engine.

Piston pin: See wrist pin.

Pit Board: Board shown to riders during a race to motivate or send a message.

Pit riding: When a racer rides his bike or a pit bike through the pits, illegal at some events and tracks.

Pitched: When the bike or the rider is thrown awkwardly due to changes in the terrain.

Pits: Outer section of the race track where riders park their bikes when they are not racing.

Plastic: Refers to the radiator shrouds, fenders, side panels, and front number plate.

Play ride: A recreational form of riding that is not training for racing.

Port: Openings in engine cylinder used for fuel entrance and the exit of exhaust.

Porting: An engine modification where the cylinder's intake and exhaust ports are widened to  increase flow into and out of the engine.

Power Valve: A valve in a carburetor or in the cylinder that is operated by vacuum or mechanical linkage to provide more fuel at wide open throttle.

Power Valve Cover: Metal piece that covers the power valve. Attached to the side of the cylinder.

Powerband: The point at which a two stroke engine's power engages.

Practice: The time a rider spends on his bike preparing for a race. Also, a specific time set aside just before a race where riders can familiarize themselves with the track.

Premix oil: Lubricant which is mixed with the gasoline in order to lubricate the cylinder. Also called 2-stroke oil.

Pressure: The force due to the weight of a substance exerted over the area the substance occupies. In metric measure, it is the force acting on each square meter. To calculate pressure, divide the force (in newtons) by the area (in square meters). It is measured in newtons per square meter (N/m²). In Imperial (U.S.) measure, it is measured in pounds per square inch (lb/in.²) (psi). Also, can refer to one rider riding closely behind another in a race to try to find a good opportunity to pass.

Pressure plate: That part of a clutch assembly that through spring pressure, squeezes the clutch disc against the flywheel thereby transmitting a driving force through the assembly. To disengage the clutch, the pressure plate is drawn away from the flywheel via linkage. 

Pro: The highest skill level of racing. (Supercross and Nationals)

Pull Rod: Metal piece found in the linkage which connects rear shock to the swingarm.

Purse: Prize money that the pros win when they win.

Race gas: Refined gasoline, usually with a higher level of octane which helps the bike engine to run cooler.

Race Sag: The amount that the seat drops when a rider sits on the bike. Used to correctly adjust suspension for rider's weight.

Radiator: A device that cools the liquid in the cooling system by allowing it to circulate through a series of water channels, which are exposed to air ducts. Found under the radiator shroud.

Radiator Shroud: Plastic piece connected from the radiator to the gas tank which protects the radiator.

Rake:  The front forks forward steering angle taken from a vertical plane 90degrees to the ground and up the line of the forks.

Ramp: Anything that a motorcycle can catch air off of.

Ratio: A fixed relationship between things in number, quantity or degree. For example, if the fuel mixture contains one part of gas for fifteen parts of air, the ratio would be 15 to 1.

Ratio Rite: A translucent plastic measuring cup which allows for proper pre-mix ratios from 16:1 to 70:1.

Rear Brake: Mechanism that stops the bike by slowing down the rear tire. It Consists of the lever, lines, reservoir, pads, caliper, and master cylinder.

Rear brake lever: mechanism used to activate the rear brake

Rear Brake Reservoir: Small container found on the subframe which holds the excess brake fluid.

Rear shock: The rear suspension connected from the linkage to the frame that absorbs the impact of landings for the rear tire.

Rebound: The action of a shock absorber to spring back to its fully extended state.

Red flag: Held by workers on the finish line of the track to alert the riders that the race may be restarted and riders need to stop.

Reed Valve: A one-way valve used in a two-cycle engine. It is made of a flat strip of metal that lies on the floor of the crankcase over a hole connected to the carburetor. As the piston moves up, the vacuum developed in the crankcase lifts the reed valve off the hole. The vacuum causes the fuel-air mixture to flow from the carburetor into the crankcase. Then, as the piston starts to move down, pressure increases in the crankcase pushing the reed valve down, closing the hole and sealing the crankcase.

Reeds: Thin plastic piece that flutters, causing air and fuel to mix and sprays this mixture into the cylinder. Found on the intake valve.

Riders meeting: The gathering of all of the riders at a race. Takes place right before the races begin to review any information riders may need before the race.

Riding Dirty: When a rider is deliberately inconsiderate or rude to other riders on the track. When a rider is known for taking out other riders.

Rim: Round metal piece which holds the tire. Connected to the spokes by the nipple.

Rim Lock: Rubber piece inside the tire that holds the tire to the rim.

Ring: A metal, split ring installed in the groove on the outside wall of the piston. The ring contacts the sides of the ring groove and also rubs against the cylinder wall thus sealing the space between the piston and the wall. Poor rings can cause poor compression and severe blowby. Often seen as blue smoke out the exhaust pipe.

Rhythem Section: A part of a track consisting of whoops that can be doubled, tripled or hit in all different sequences.

Roost: Dirt or debris thrown in the air from the force of a spinning rear tire.

Rotor:  A small rotating cap-like unit at the end of the distributor shaft. It is located on the breaker cam inside the cap. It connects between the center electrode and the various outer spark plug terminals as it turns, thus distributing the high voltage from the ignition coil secondary winding to the proper spark plug. 2. A rotating armature inside a stator. As the rotor turns within the stator, electricity is produced to power the electrical components. 3. A trichoidal device in a rotary engine.

RPM: Abbreviation for revolutions per minute. Indicates the amount of times the crank shaft turns in a minute.

Running Choppy: Refers to a motorcycle that is misfiring, causing improper acceleration.

Rut: An indention made in the track due to continuous riding.

Saran Wrap: Freestyle trick where rider puts one foot over the bars and completely circles it back around, lifting whichever hand is in the way and then replacing both the hand and foot for the landing.

Schoolboy: A class of racing in which any rider under the age of 16 may enter.

Seat Cover: The vinyl material that covers the part of the bike you sit on.

Semi: Racing class in the main event racing format. The race riders participate in if they did not make the main event in their
                     heat race.

Shark Fin: The metal piece that fits over and protects the rear brake caliper.

Shift lever: A metal piece located in front of the left footpeg, attached to the transmission. Used to switch gears.

Show Him the Front Tire:

Sidecar: A motorcycle that has a special attached unit with a wheel to carry a passenger.

Side Panel: Plastic piece on both sides of the dirtbike that holds the rider's number.

Side Wall: Smooth part of the tire between the bead and the tread. Typically contains the writing.

Silencer: Part of the exhaust system found under one of the side panels, connected to the exhaust pipe. Used to muffle the noise of the engine.

Silencer Packing: Fiberglass insulation found inside the exhaust pipe to help reduce noise.

Single: One ramp all by itself.

Ski jump: A jump with an especially long landing ramp which allows the rider to land on the ramp at any speed.

Skid Plate: Metal piece that attaches to the frame under the transmission. It protects the tranny.

Slip the clutch: When a rider gradually releases the clutch lever.

Spark plug: A device containing two electrodes across which electricity jumps to produce a spark to fire the fuel charge. The center electrode is insulated from the spark plug shell by means of a molded insulator resembling porcelain. The side electrode protrudes from the bottom edge of the spark plug shell and is so positioned that there is a gap between it and the center electrode.

Split the cases: When the transmission is taken apart for mechanical servicing.

Spode: A rider that has no skill, but does not realize it and never improves. Typically can be found giving bogus advice to other riders.

Spoke: Thin metal part of the wheel that connects the rim to the hub and can be adjusted to true the rim.

Sprocket: A metal gear that transfers power from the engine to the chain or from the chain to the rear wheel.

Squid: An inconsistent and dangerous rider.

Squirrel: An inconsistent and dangerous rider.

Staggered gate: This occurs when track officials choose to run two races at once. They do this by starting the first race, putting the gate back up, and starting the second race. Usually the two races are still scored separately.

Staging: Area where riders gather to prepare to line up at the starting gate.

Stall: When the bike's engine stops running for any reason.

Starting Box: The box which holds the mechanism that drops the starting gate. Located in the middle of the starting line.

Static Sag: A term used when setting race sag. Also none as Free Sag. This is the measurement of how much the suspension droops without the rider and is one way of measuring whether the spring is too light or too stiff for the rider.

Stator:. The fixed electrical windings on a magneto, alternator, or generator. It turns within the rotor.

Steering Stem Bearings: Bearings used to turn the front wheel.

Steering Stop: Located on the lower triple clamp. Metal pieces that stop the front end from turning too far.

Step-up: A jump built into the track. Looks like a stairstep.

Step-off: When a rider intentionally jumps off his bike.

Sterilizer: A freestyle trick where the rider puts both feet over the handlebars between his hands, keeping both hands on the grips, and landing in that position.

Stock: A motorcycle which has all factory parts and no after market parts. Also a class of racing in which only stock bikes may enter.

Stoked: Term used to describe excitement of a rider.

Stoppie: When a rider pulls in the front brake causing the bike to pitch forward into an endo-wheelie and continues moving.

Stork:A freestyle trick in which the rider sticks his legs backwards far above the seat.

Stuck in the Gate: When a rider takes off before the starting gate drops and becomes caught.

Studders: Multiple jumps in a row that are very little, like whoops, but smaller.

Stuffed: Term used when one rider passes another on a corner and forces him to the outside edge of the track.

Subframe: Metal piece on the bike connected to the frame that holds the air box, the side panels, the rear fender, and the seat.

Supercross: An American professional series race held indoors at a stadium. Tracks consist of larger jumps.

Superman: A freestyle trick where the rider keeps his hands on the grips and straightens his body and legs above and parallel to the bike.

Supermini: A class of racing that only includes modified mini bikes.

Swap: When the back end of the bike jumps to the right and left, usually caused by bumps in the course.

Sweeper: A corner that is not sharp and riders can maintain speed around.

Swingarm: Metal piece connected to the rear axle and the frame that holds the rear wheel on.

Switchblade Can-Can: A freestyle trick in which a rider turns his body around in the air with his feet sticking out to the side of the bike and crosses his legs.

Synthetic Oil: An oil produced by chemical processes rather than occurring naturally.

T-Bone: When one rider runs directly into the side of another rider and usually takes them out.

Table top: A jump with a flat top. Object is to clear the flat area and land on the downslope of the far side.

Tacky: When the track is moist and sticky, it is referred to as being tacky, tires get good traction when the track is tacky.

Tap the back brake in the air: Jumping technique used when the front end is too high while the rider is in the air. Rider presses the back brake with the right foot which stops the rear tire and forces the front end to drop or raises the rear end.

Tapped Out: Refers to the top speed of each gear on the bike. For example: "I was tapped out in third."

Tattoo: Skin art.

Tear off: Thin disposable plastic sheet that goes over the lens of goggles. Rider can use multiple tear offs and remove them throughout the race to clear mud from his vision.

Terrain: Ground fit for riding.

Three Fingers: A common form of measurement used to check the correct tension on bike chain.

Throttle: The device that controls the vacuum created in the Venturi of the carburetor. The greater the vacuum, the richer the fuel-air mixture. The throttle enables the engine to run on a richer mixture and produce more power for high-speed.

Throttle Cable: Line running between the twist throttle and the carburetor. Raises and lowers the needle and the slide inside the carburetor which regulates how much fuel is let into the cylinder.

Throttle Valve: Metal slide located in the carburetor used to keep the needle alined when accelerating and decelerating.

Timing: A term referring to rider's sense of judgement on landings and other skills.

Tire: Rubber piece attached to the rim that touches the ground. Used for traction and some impact absorption.

Took me out: Phrase used when one rider intentionally causes another rider to crash.

Top Dead Center: (TDC) Highest point of piston and connecting-rod travel in a cylinder; the ends of the compression and exhaust strokes in a four-cycle engine.

Transfer Position: In the main event racing format it is the selected heat, semi, and last chance qualifier positions that will let a rider continue into the main event.

Transmission: The mechanical system, including gears and shafts, by which power is transmitted from the engine of the bike to the drive wheel. Also a set of gears and the protective casing that covers this in a vehicle or engine.

Tread: The outside part of the tire which provides traction.

Trick: Freestyle maneuver.

Triple Clamp: Clamps that hold the front suspension onto the frame of the bike. They also hold the handlebars on the bike.

Triple: Jump made of three ramps. Object is to clear all three and land on the downside of the farthest one.

True: When a rim is properly straightened. Can be adjusted by tightening the spokes on the wheels and needs to be done any time a rider spins the wheel and it wobbles.

Turn it Over: Term used whenever someone attempts to start a bike. Can be used to tell someone to kick start their bike.

Tweaked Bars: Handlebars that are bent from a crash.

Twist Throttle: The right grip on the handlebars which is used as a means of acceleration by rolling it towards the rider.

Twitch: A freestyle trick in which the rider puts one leg over the bars and one leg out to the side of the bike and then places them back on the pegs for the landing.

Two stroke: A reciprocating engine cycle in which the piston takes over some of the valve functions in order to obtain a power stroke each revolution of the crankshaft. This involves the use of ports in the cylinders which are covered and uncovered by the movements of the piston. As the piston moves down, it clears these ports so that the exhaust gases can exit and a fresh charge of mixture can enter at the same time. In a typical two-stroke engine the fuel-air mixture enters the crankcase through a reed valve. When the piston is at the bottom of the cylinder a port is uncovered. As prior movement of the piston has compressed the mixture in the crankcase, it flows into the cylinder. Further compression in the cylinder starts as soon as the piston reverses and covers the ports. At the same time compression is occurring in the cylinder, movement of the piston has created a vacuum in the crankcase which draws a fresh charge of mixture from the carburetor into the crankcase. The compressed charge is fired as the piston reaches top dead center. As expansion of the burning charge forces the piston downward, the reed valve in the crankcase closes and the mixture in the crankcase is compressed. As the piston uncovers the ports at the bottom of the stroke, compressed mixture from the crankcase enters the cylinder again and is deflected by a baffle on the piston head into the outer end of the cylinder. This incoming fresh mixture then assists in pushing the burned gases out of the cylinder and the cycle is repeated.

Vent Hose: Tube connected to the gas cap which gives the gas tank proper ventilation.

Vet class: Class of racing where only racers age 50 and over may enter.

Vintage: Refers to a bike that is many years old. Also a class of racing where only vintage bikes may enter.

Visor Grind: A freestyle trick in which the rider touches his visor to the front fender.

Visor Grind Fender Grab: A freestyle trick in which the rider touches his visor to the front fender and grabs the front fender at the same time.

Wad It Up: A crash typically resulting from an endo and causing the rider to land on his head.

Washed Out: Any time a rider's front tire slides out to one side or the other.

Water Pump: A device that circulates the liquid through the cooling system by pumping it from the engine water jackets to the radiator. The pump is usually mounted at the front of the engine and is driven by a belt from a pulley on the front end of the crankshaft.

Water the Track: When officials spray water on the track's dirt, this makes the terrain more tacky to create better traction for racers.

Wheelie: When a rider accelerates and the front wheel lifts up off of the ground.

Whip: Freestyle trick in which rider lays the bike flat horizontally in the air and then brings it back up for the landing.

White flag: Waved to indicate one lap left in the race. Can be seen by riders on the finish line.

Whoops: Mogul-like section of the track typically consisting of more than 10 tiny jumps in a row.

Wide open: Refers to the top speed of each gear on the dirt bike. For example: "I was wide open in third."

Wrist pin: A metal piece that holds the piston onto the crankshaft.

Yellow flag: Held by track workers who are randomly placed on the track, used to caution riders about hazards on the course.