|Acceleration: The rate of change of velocity or speed. Velocity is steady and is measured in distance per time (e.g., feet per second, miles per hour, kilometers per hour). Acceleration keeps increasing and is measured in velocity per time (e.g., feet per second per second or feet per second squared) |
After Market: Any bike part that isn't factory built Air box: The plastic box that contains the air filter, protecting it from elements. Underneath the seat of motorcycles. Air filter: Foam piece that removes dirt and water from the air before it reaches the carburetor. Amateur: Any rider not on the professional level. Beginner, Novice, Intermediate, Expert Arm pump: Forearm fatigue caused from the strain of riding for an extended period of time. Attack Position: The body position a rider has when he is accelerating or air borne. Axle: Shaft that holds the wheel on the bike. Attached to the front suspension on the front of the bike and the swing arm on the rear.
Back flip: The rider flips while in the air (360 degrees) and lands.
Backward Falling Gate: Starting gate falls towards the rider.
Bailed: Rider that purposely ditches the bike, ditches, throws the bike to avoid a hazardous situation.
Banging Bars: You and another rider are having a battle for position and contact is involved.
Bar Hop: Where a rider puts both feet over the handlebars between his arms and then returns them for the landing
Bark busters: Used for trail riding/dense tree areas. Metal pieces that protect your hands from trees that are attached to the handle bars.
Bar Mount: Metal clamp that connects the handlebars to the triple clamp.
Bar Pad: The protection device made of foam found on the crossbar of the handlebars.
Base Gasket: Gasket directly below the cylinder, between the cylinder and crankcase.
Basket case: An old bike that does not run. Engine and transmission parts may have been removed, missing or stored in the trunk or a "basket".
Beginner: Lowest amateur skill level of racing. Beginner, Novice, Intermediate, Expert.
Berm: Built up outside edge of a corner on a track.
Big bike open: A racing class. Any skill level rider that rides a bike 125cc and above can enter.
Big bikes: Dirtbike larger than 125cc.
Big Wheel: Any motocross bike that is bigger than an 80, but smaller than a 125. This term usually refers to the Kawasaki 85cc big wheel and the newer 100cc big wheel.
The Bike Died: Engine stops running unintentionally.
Bike stand: A metal device used to hold up a motorcycle when stationary. Also called a stand.
Black Flag: Black with 1-inch white boarder-disqualification of a rider. That rider must report to the referee at once.
Bleed the brakes: Removing air from brake lines.
Blip the Throttle: Gives the bike a quick short burst of acceleration. Useful in trying to control the bike in certain situations.
Block pass: Used when one rider passes by aggressively cutting in front of another. In some cases, physical contact is made.
Blown Fork Seal: When fork seal visibly leaks fork oil.
Blue flag: Light blue with diagonal yellow stripe- indicates you are about to be overtaken by faster riders. Hold your line and do not impede their progress.
Blue Groove: When dirt on the track is very dry, hardpacked, and appears blue or black from the rubber off of tires.
Bogging: Low pitch sound of a motorcycle engine that is not getting enough RPM REV. Needs to down shift or apply more throttle to go faster to create power.
Bogging down: When you are trying to accelerate and your bike is not in the power band.
Bottomed Out: When a bike's shocks are completely compressed due to a hard landing. When this happens the wheel will hit your fender creating a black mark on the bottom surface.
Brake Cable: Line running between the front brake reservoir and the front brake master cylinder. Transfers pressure produced by the brake lever through the line to the master cylinder.
Brake pads: Metal plates that press against the brake disc or rotor to enable the wheel to stop.
Brake Pin: Metal piece on the brake caliper that holds the brake pads in place.
Brake Slide: When entering a corner the back tire slides due to locking up the back brake, before you begin to accelerate out of the corner.
Braking Bumps: Places on track just before corners where riders have continually used brakes, creating small bumps.
Cable Luber: Device used to lubricate the clutch cable.
Caliper: The apparatus on disc brakes which hold the disc pads and straddles the disc. When actuated the pads press against the disc to stop or slow the vehicle. 2. An adjustable measuring tool that is placed around (outside caliper) or within (inside caliper) an object and adjusted until it just contacts. It is then withdrawn and the distance measured between the contacting points.
Can-can: Rider puts one foot over the seat in front of the other and replaces it for the landing.
Came in too hot: When rider carries a to much speed into a corner, possibly making the rider miss the corner.
Came Up Short: fail to completely clear obstacle. (rider fails to clear jump)
Camelback: A jump built into the track. One bigger ramp in the center of two smaller ramps.
Carburetor: A device that vaporizes fuel and mixes it with air in proper quantities and proportions to suit the varying needs of the engine. A filter screens the air which is drawn into the carburetor. Here the gasoline mixes with the air and this fuel vapor enters the combustion chamber through the intake valve where it is compressed and burned.
Case Cover: A metal piece on the side of the transmission that covers the clutch components.
Case plate: Metal plate underneath bike that creates extra protection for the transmission.
Cubic centimeters CC: Standard metric form of measurement used to measure the volume amount of oil in a gear box and the amount of space in the cylinder. This determines the size of the motorcycle. 50cc, 80cc, 85cc, 125cc, 250cc, 500cc,
Chain: Linked metal that runs from the front sprocket to the back sprocket to create rotation.
Chain Adjuster: Bolt on the rear of the swingarm that is loosened or tightened to change the slack in the chain. When adjusted, the rear wheel moves forward and backward.
Chain Lube: Liquid used to protect the chain from dirt, rust, and wear.
Chain Roller: Keeps the chain from hitting the frame and the swing arm.
Chain Slider: Rubber piece that protects the swingarm from the chain.
Charging a Corner: When a rider approaches a corner very quickly and aggressively.
Chassis: Refers to the frame, engine, front and rear axles, springs, steering system, and fuel tank. Can be everything but the body or cab and fenders.
Checkered flag: Official signaling end of race.
Choke: A butterfly valve or plate located near the top of the carburetor that limits or restricts the amount of air allowed to enter the carburetor, thus enriching the fuel-air mixture and enabling the bike to start and run more easily when cold.
Choping the throttle: Suddenly letting off of the throttle while accelerating. Circlip: Small circular metal piece that holds the wrist pin in place inside the piston.
Classes: Division of skill levels between riders.
Clicker: Clutch: A device that disconnects the engine from the transmission, to allow the vehicle to change gears, and then allows the engine and transmission to resume contact and turn together at a new speed. The clutch consists of a series of parts: clutch lever, clutch cable, clutch perch, clutch adjuster, pressure plate, springs, basket, fiber and metal plates.
Clutch Adjuster: Device that loosens or tightens the clutch lever freeplay. Located on the clutch cable or on the clutch perch.
Clutch Basket: Metal basket in transmission that holds the clutch plates.
Clutch Cable: Cable running between the clutch lever and the transmission. Allows the clutch to engage and disengage.
Clutch Cover Gasket: Rubber piece that forms a seal between the clutch cover and the transmission, keeping oil in and maintaining pressure.
Clutch Lever: Lever attached to the left side of the handlebars. Engages and disengages the clutch.
Clutch Perch: Holds the clutch lever onto the handlebar. Also connects the clutch cable to the clutch lever. Clutch plate: Discs that remove the force of the motor from the transmission.
Clutch Spring: keeps pressure between the clutch basket, clutch plates, and the pressure plates.
Coffin: Rider lies back on the bike, sticks his feet forward while holding on to the handlebars.
Coil: Transformer for increasing the voltage to fire the spark plug or plugs.
Compress: Rider utilizes the suspension to jump higher.
Compression: One of the essential factors in internal combustion engine (fuel, air, proper proportion of mixture, compression, timing, spark). It is the squeezing of the fuel-air mixture in the cylinder of a spark-ignition engine. Compression makes the process of combustion more effective and increases engine efficiency.
Compression Stroke: The second stroke of the four-stroke cycle, in which the piston moves upward from bottom dead center to top dead center, compressing the fuel-air mixture.
Concrete Start: Starting pad that is made of concrete.
Conditions: The state that the track is in--muddy, tacky, or hard packed.
Conventional Forks: Suspension commonly used in the past, female component holds the axle, male component is held by the triple clamp.
Coolant: Liquid in the cooling system. Can be a mixture of water and antifreeze (ethylene glycol). This mixture lowers the freezing point of the water in the cooling system, prevents rust and corrosion, lubricates the water pump, and picks up heat from the engine and transfers it to the air passing through the radiator.
Cordova: A freestyle trick in which the rider puts his feet up to the bars and does a backbend, then replaces his feet back onto the pegs for the landing.
Crossbar: Gives handlebars added support.
Cylinder: Sits on top of the transmission, allows the piston and rings to operate along with the spark plug to make the engine fire.
Cylinder bored: Widening the cylinder to give more space for a larger piston and ring. By doing this you will get more horse power.
Cylinder Head: (aluminum or iron) section bolted to the top of the cylinder block. Used to cover the tops of the cylinders, in many cases the cylinder head contains the valves, forms part of the combustion chamber, then has water and oil passages for cooling and lubrication.
Cylinder Sleeve: Innermost part of the cylinder.
Dash for Cash: A race held during intermission, a bucket can be passed around for everyone to donate money for the winner to take. Other events riders pay to enter and the first place finisher may win all of the entry fees. Dead Sailor: When a rider jumps over a freestyle jump and does not attempt a trick.
Decompress: Technical jumping technique: The rider tries to stay as low to the ground as possible over a jump in order to get back on the ground faster. Disc brake: A type of brake that has two basic components: a flat rotor (disc) that turns with the wheel and a caliper that is stationary. When the brake pedal is depressed, linkage (mechanical or hydraulic) causes the caliper to force its heat-resistant brake pads against both sides of the rotating disc thus slowing or stopping the wheel. DNF: Scorekeeping term, "did not finish"
DNS: "did not start". As in the rider did not start the race. Double jump: Two jumps together, to do a double jump the rider should clear both jumps landing on the downside of the second.
Drop the clutch: When a rider quickly lets out the clutch instead of slowly releasing the clutch.
Dust Bowl: When the track is very dusty and causes limited vision for riders. Dyno: Is used to measure the horsepower and torque of an engine.
Endo: A rider is pitched forward face first.
Exhaust Port: Where the exhaust fumes leave the cylinder and enter the exhaust pipe. Expansion Chamber: The widest part of an exhaust pipe.
Expert: The highest skill level of amateur racing. Beginner, Novice, Intermediate, Expert
Face plant: When rider crashes and lands on his face.
Fade: When a rider gets worn out and drops back in the field.
Fender grab: A freestyle trick in which the rider grabs one of the fenders. Filter Oil: Product put on the air filter to help keep dust and debris from entering the engine.
First turn: The first corner in the track following the drop of the gate. Also the point where the holeshot is determined.
Flag Mount: Holds a flag onto a motorcycle’s swing arm when riding in the dunes.
Flagger: Track workers that are placed on the side of the track and look for hazards on course such as crashes or animals. When a hazard is spotted they wave a caution flag depending on the severity of the hazard.
Float: 1. A small hollow tank which is more buoyant than the liquid in which it is immersed. In a carburetor it operates the valve (needle and seat) which controls the amount of fuel entering the carburetor. In the fuel tank, it indicates the amount of fuel. Also see valve float. Older floats were hollow and made of metal, but newer ones were made of a solid synthetic material. 2. The action of the breaker arm when it is pushed out as the cam strikes the rubbing block; and before the arm can return after the cam has passed, the next cam strikes the block and re-opens it. In other words, the breaker arm never has the time to fully close before being opened again.
Float Bowl: A reservoir for gasoline where the float is placed. The float controls the amount of fuel moving through the fuel valve.
Flooded: When too much fuel enters the cylinder and drowns out the spark plug, causing the bike not to start.
Fly wheel: Large and heavy wheel attached to the back of the crankshaft to smooth out the firing impulses. It provides inertia to keep the crankshaft turning smoothly during the periods when no power is being applied. Also forms a base for the starter gear in a manual transmission, for the clutch assembly. Can be called "engine flywheel."
Foot peg: The foot peg is a metal piece connected to the frame that the rider stands on.
Fork guards: Plastic cover for the male section of the front suspension, protects it from dirt and debris.
Fork Oil: Product used for pressure and lubrication in the front suspension of a motorcycle.
Fork Seal: Rubber piece on front suspension which keeps fork oil from leaking out and creates an air tight seal.
Fork Spring: A spring inside of the front suspension tubes, used to absorb impact and rebound the suspension.
Fork Tube: Front part of the suspension which holds the spring and allows the male section to operate.
Four stroke: An engine requiring two complete revolutions of the crankshaft to fire each piston once. The first stroke down (intake stroke) pulls fuel and air into the combustion chamber. The second stroke up (compression stroke) compresses the mixture. The third stroke down (power stroke) comes about through the rapid burning of the compressed . The fourth stroke up (exhaust stroke) expels the exhaust gases from the cylinder. It is also called the "Otto cycle."
Frame Guard: A metal or plastic piece that attaches to the frame above the foot pegs. It protects the frame from wear and tear.
Free Sag: A term used when setting race sag. Measurement of how much the suspension droops without rider. Is one way of measuring whether the spring is too soft or too stiff.
Freestyle: Style of riding in which riders perform tricks over jumps.
Freestyle Ramps: Specifically designed ramp/jump to perform tricks.
Front Brake Master Cylinder: Hydraulic brake system which stores the brake fluid. As the brake pedal is applied pressure is forced against a small movable piston in the master cylinder to push hydraulic fluid through the lines to the wheel cylinders and force the brake linings against the drum (in the case of drum brakes) or force the brake pads against the disc (in the case of disc brakes).
Front Brake Reservoir: Small container connected to the top right side of the handlebars, which holds the excess brake fluid.
Front end washes out: Front end of the bike slides sideways or out of from under you, due to loss of traction while in motion. Could cause one to crash.
Front Number Plate: Plastic piece on the front of the bike used to block debris and display racing number. Front Suspension: Connect from the triple clamps to the front axle, and absorbs the impact of the track terrain.
Full waffle grips: Grips which are fully textured.
Gas Cap: Lid on gas tank that can be removed to check level of fuel or to add fuel.
Gas Tank: Container for holding or storing fuel, located between the seat and the radiator.
Gasket: Material made of asbestos, cardboard, cork, paper, rubber, or soft metal placed between two metal parts to insure proper sealing.
Gear: Wheel-like part with teeth cut into the rim. When one gear meshes with another gear, it causes the second gear to drive the other and in this way transmits power. When the gears are different sizes (different number of teeth on each gear) the mechanical average is changed. Can also refer to riding apparel.
Gear Bag: Bag used to carry any gear or items used when riding.
Gear box: The device in the drivetrain consisting of an input shaft, a system of gears, and an output shaft that multiplies engine torque. A manual transmission consists of a clutch assembly plus a gearbox; and automatic transmission generally consists of a torque converter plus gearbox.
Gear Ratio: Number of turns made by a driving gear to complete one full turn of the driven gear. If the driving gear turns four times to turn the driven gear once, the gear ratio would be 4 to 1. In most instances, the gear ratio is not even like 4:1 because the same teeth would be meshing each other. Thus a ratio of 4.11:1, for instance, means that a particular tooth on one gear may eventually mesh with every one of the teeth on the other gear. Changing the tire size will change the effective gear ratio.
The Gate: Starting gate or gate which encloses the entire track grounds.
Gates Open: What time the facility will be open to the public.
Goggle Lens: (Lens) Transparent plastic part of goggles that shield eyes from debris. Come in several types: clear, yellow, mirror, gray, hologram, orange, fog resistant, double pane.
Goggles: Eye protection used by motocross racers.
Going Big: Rider jumps further, and higher than normal.
Goon: An outdated, inappropriate, dangerous, or squarely rider. Also referred to as Spode, Nerd, Dork, Squirrel Grab Holes: Holes under the seat that freestyle riders use to hold on to the bike when doing tricks.
Graphics: Stickers placed on the plastic of a motorcycle for looks or advertisement.
Green flag: Start of race
Grips: Rubber pieces covering the ends of the handlebars. Provides traction and impact absorption.
Half Waffle Grips: Grips which are half smooth and half textured.
Hand guards: Plastic covers connected to the front of handlebars which protect rider's hands from dirt and debris.
Hardpack: Track condition is dry and firm.
Head: Covers the piston and creates the combustion chamber. The proper name is cylinder head.
Head Gasket: Sits between the cylinder and the head. Keeps the coolant out of the cylinders and retains compression in the cylinder.
Head milled: Remove metal from the bottom of the head by a rotating toothed cutter. Decreases air space in the engine and increases compression.
High RPM: Engine running in mid to full throttle. RPM stands for rotations per minute, 1 rpm is the crankshaft making 1 full rotation.
Holeshot: Leader into the first turn of a race.
Hub: The center of a wheel consisting of a shell to which spokes attach and contains an axle along with two sets of bearings.
Idle: Engine speed when the bike is not moving, the engine's slowest practical speed. Indian air: Rider puts his legs behind the bike, crosses them, and then replaces them for the landing.
Indoor: Any event held inside a stadium or covered arena, out of the elements.
Inside line: Inner part of a turn. The rider took the inside line rather than the outside.
Intake Boot: Channels the air from the air box into the carburetor.
Intake valve: Valve that opens to permit fuel mixture into the cylinder. Closes during the compression and combustion strokes. Some engines have more than one intake valve to each cylinder. Also called the "inlet valve."
Intermediate: Amateur skill level of racing just below expert. Beginner, Novice, Intermediate, Expert
Inverted Forks: Commonly called "upside down forks". Male component holds the axle and female component is held by the triple clamp. Intake Port: Opening in the cylinder where fuel enters.
Jet: Fuel tube or pipe in the carburetor, Air is admitted through one or more holes to compensate for a tendency of the main nozzle to deliver too rich a mixture as the air velocity through the carburetor increases. Also called "air bleed." Jetting: When you adjust the size of components in your carburetor to get the proper mixture of gas and air. Jump the Gate: When a rider takes off before the starting gate drops and possibly becomes caught.
Kick it Over: Attempt to kick start a bike. Kick Starter: Metal lever on the right hand side of the bike that is used to start the engine.
Kicker: A jump that has a bump, lip, sticking up on the top right before you launch. Jumps with a kicker will send a rider into an endo position if not careful.
Kidney Belt: A protective wrap worn around the waist, which guards kidneys from injury. Kill Switch: Located on the left side of the handlebars. When pushed the motor is killed/ shut off.
Knee Pads: Protective pads used to guard, and help protect the knee from injury.
Lapper: Rider that is a full lap behind.
Last Chance Qualifier: (LCQ) In main event style racing format, this is the last opportunity for a rider to advance into the main event. Often only 2 or 3 riders will make it out of the LCQ.
Lifter: A lifter that uses hydraulic oil pressure to maintain no clearance between metal parts so that valve noise is reduced. Also it reduces wear on the valves and eliminates periodic valve adjustments.
Line: The path a rider chooses to go through a section of a track or around a turn. Riders work very hard to find the best and fastest lines on the track. Lines that can be used for passing, and lines to use when the track starts to changes.
Linkage: A series of rods, levers, bars or links used to transmit motion from one unit to another. Connected from the swingarm to the rear shock.
Look back: When a rider glances behind him to assess where the other racers are in relation to him.
Loopout: When a rider sits to far back on the seat and gives is in the air and the front end goes too high. Can cause panic rev or a crash. Can be corrected by tapping the back brake.
Low End: Lower section of the powerband. Also lower part of the engine, connecting the rod and crankshaft.
Low RPM: When the engine is running at mid to low throttle. RPM stands for rotations per minute. 1 rpm is when the crankshaft does one full rotation.
Magneto: An electrical device which generates electrical current when it is rotated by an outside source of power. It needs no outside source of power such as a battery. It may produce either low or high tension current.
The Main: (Main Event) It is every riders goal to make the main event.
Main Jet: Located inside the carburetor used to mix air and fuel.
Master cylinder: The primary component for pressurizing fluid in a hydraulic system. Used in the braking system, it supports a reservoir for holding brake fluid and is activated each time the driver depresses the brake pedal.
Master link: A special link on a chain that can be opened by flexing a plate, removing a screw, or some other means besides driving out a rivet out.
Match the cases: Engine modification where both parts of the transmission are aligned perfectly to increase engine performance.
Midrange: Middle section of the powerband, there is a low, mid, and high range.
Mini: Name used for an 80cc dirt bike or an 80cc racing class.
Modified: A bike becomes modified when after market parts are added that will improve performance over a stock motorcycle. Can also be a racing class where only modified bikes may enter. Mulisha Air: (Superman seat-grab)
Nac-nac: Rider brings one leg over the seat, and then puts his foot back on the peg to land
Needle: 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: Rider puts both 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: Rider takes both of his hands off the bars and lands the bike.
No hander Nothing: Rider takes his hands and feet off of the bike and then replaces them for the landing.
Novice: Amateur skill level just after beginner. Beginner, Novice, Intermediate, Expert
Off Camber: 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. When a motorcycle is on the pipe, it is running at the rpm that gives maximum horsepower.
One hander: 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 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: 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 used to control the flow of liquid. A petcock on a motorcycle is the line coming from the fuel tank.
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: Mixes air and fuel, and located inside the carburetor.
Pinned: Motorcycle that is at its maximum RPM. If a rider is going very fast one may refer to the rider as he or she has it pinned.
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: Spring or piece that connects the exhaust pipe to the frame of the motorcycle to stabilize it.
Piston: Connected to the rod and the ring inside the cylinder of the motor. Used to support the ring and create compression in the engine.
Pit Board: Board used to send a message to a rider while on a track.
Pit riding: When a racer rides his bike through the pits. You are supposed to go slow while pit riding and can be 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: Radiator shrouds, fenders, side panels, and front number plate.
Play ride: Recreational form of riding that is not training.
Port: Openings in engine cylinder used for fuel entrance and the exit of exhaust.
Porting: Modification to the cylinder's intake and exhaust ports are widened to increase flow into and out of the engine.
Power Valve: A valve in the carburetor or the cylinder and operated by vacuum. A mechanical linkage, that provides more fuel at wide open throttle.
Power Valve Cover: Metal cover over power valve, attached to the side of the cylinder.
Powerband: A point when a two stroke engine's power engages. When the powerband engages you feel a surge of power and acceleration.
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: Mixture of oil and gasoline that lubricates the cylinder. Also called 2-stroke oil.
Pressure plate: Engaging the clutch applies spring pressure, which squeezes the clutch disc against the flywheel 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: Part of a linkage that connects the rear shock to the swingarm.
Purse: Total amount of prize money that can be won at an event.
Race gas: Refined gasoline has a higher level of octane, which helps the bike engine run cooler and create more horse power.
Race Sag: The amount the seat drops when a rider sits on the bike. This will allow you to correctly adjust the suspension for the 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.
Radiator Shroud: Plastic piece that connects from the radiator to the gas tank and protects the radiator.
Ramp: Anything a motorcycle can catch air or off the ground is considered a ramp.
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 allowing 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: Lever used to activate the rear brake.
Rear Brake Reservoir: Small container found on the subframe which holds the excess brake fluid.
Rear shock: Suspension connected from the linkage to the frame that absorbs impact from the rear tire.
Rebound: How fast or slow the action of a shock absorber springs 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: Rider deliberately takes another rider out is inconsiderate and rude, to other riders on the track. A rider may be labeled as a dirty rider if he takes other riders out. By hitting them with his motorcycle or pushing them off the track in order to not be passed. Rim: Round piece that holds the tire. Rim Lock: Rubber piece inside the tire that holds the tire to the rim. Ring: A split ring goes around the groove of the piston. The ring makes contact against the cylinder wall sealing the space between the piston and the wall. Poor rings cause poor compression.
Rhythm Section: Part of a track whoops or jumps, 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. RPM: Abbreviation for revolutions per minute. Indicates the amount of times the crank shaft turns in one minute.
Rut: An indention made in the track due to continuous riding.
Saran Wrap: Rider puts one foot over the bars and completely circles it back around, lifting whichever hand is in the way then replaces both for the landing. Schoolboy: A class of racing in which any rider under the age of 16 may enter.
Seat Cover: 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: Lever in front of the left foot peg, used to shift gears.
Side Panel: Plastic piece on both sides of the dirtbike that holds the rider's number.
Silencer: Used to muffle the noise of the engine, and is found under one of the side panels, connected to the exhaust pipe.
Silencer Packing: Fiberglass insulation found inside the exhaust pipe to help reduce noise.
Ski jump: A jump with a long landing ramp which allows the rider to land on the ramp at any speed. Skid Plate: Attaches to the frame under the transmission. This will protect the bottom of your engine if you were to hit something that could cause damage.
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 doesn’t realize it and looks out of place on a motorcycle track. Gives bogus advice. 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: Inconsistent and dangerous rider.
Squirrel: An inconsistent and dangerous rider.
Staggered gate: 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. The two races are still scored separately and are not in competition with one another.
Staging Area: Where riders gather to prepare to line up at the starting gate.
Stall: When the bike's engine stops or just quits running.
Starting Box: Holds the mechanism that drops the starting gate. Located in the middle of the starting line.
Static Sag: Term used when setting race sag, and could be called Free Sag. This is the measurement of how much the suspension droops without the rider. Is one way of measuring whether the spring is too light or too stiff for the rider.
Stator: Fixed electrical windings on a magneto, alternator, or generator, and turns within the rotor.
Steering Stem Bearings: Bearings used to turn the front wheel.
Steering Stop: Located on the lower triple clamp, stops the front end from turning too far.
Step-up: Jump that looks like a stair step and requires you to jump up on top then back off normally. Sterilizer: 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 for only stock motorcycles to race in.
Stoked: Used to describe excitement of a rider.
Stoppie: Rider uses the front brake causing the back tire to pitch forward, off the ground into an endo-wheelie and continues moving. Stork: Rider sticks his legs backwards far above the seat.
Studders: Very little jumps in a row, like whoops, but smaller.
Stuffed: When a rider passes another on a corner and forces him to the outside edge of the track.
Subframe: Frame that holds the air box, the side panels, the rear fender, and the seat.
Supercross: Race held indoors at a stadium. Track have larger jumps, very technical and only pros are aloud to race at these events.
Superman: Rider keeps his hands on the grips and straightens his body and legs above and parallel to the bike.
Supermini: Only includes modified mini bikes to race in this class.
Swap: Back end of the bike starts jumping, back and forth right and left, caused by bumps in the course.
Sweeper: Corner that is not sharp, long sweeping turn where riders can maintain speed.
Swingarm: Metal piece connected to the rear axle and the frame that holds the rear wheel on.
Switchblade Can-Can: 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: Oil produced by chemical processes rather than occurring naturally.
T-Bone: Rider runs directly into the side of another rider and takes that rider out.
Table top: 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 tacky. Your tires well get the best traction in these conditions.
Tapping the back brake in the air: Technique used when the front end gets too high in the air. Rider presses the back brake, stops the rear tire and forces the front end to drop.
Tapped Out: The top speed of a gear, couldn’t go any faster in that gear. For example, I was tapped out in third.
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: Type of ground you are riding on.
Three Fingers: A common form of measurement used to check the correct tension on bike chains.
Throttle: 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: Cable running between the 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: Slide in the carburetor that keeps the needle aligned when accelerating and decelerating.
Timing: When a rider can judge a jumps distance and do it perfectly over and over. He is said to have good timing. Timing is critical in Supercross Tire: Rubber attached to the rim that touches the ground. Used for traction and some impact absorption.
Took me out: Used when a rider intentionally causes another rider to crash.
Top Dead Center: 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 a qualifying race for the main event this is the last positions that will allow the rider to transfer and continue into the main event.
Transmission: Gears and shafts, by which power is transmitted from the engine of the bike to the drive wheel.
Tread: Outside part of the tire that provides traction.
Triple Clamp: Holds the front suspension, and the handlebars to the frame of the motorcycle.
Triple: Three jumps in a row. If you have enough experience, the goal is to clear all three, and land on the downside of the farthest one.
True: Rim is properly straightened. A rim is trued by adjusting and tightening the spokes on a wheel.
Turn it Over: An attempt to start something, or to tell someone to kick start their bike.
Tweaked Bars: Handlebars that are bent.
Twitch: Rider puts one leg over the bars, and one leg out to the side of the bike, then returns them back on the pegs for the landing.
Two minute board: A rectangular board used by the starter to make the riders aware the race is starting with in 2minutes. When the starter turns the board sideways, the riders know that the gate will drop within five seconds.
Two stroke: 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: Racers age 50 and over may enter.
Vintage: Bike that is old. Class of racing where only vintage bikes may enter.
Visor Grind: Rider touches his visor to the front fender.
Visor Grind Fender Grab: Rider touches his visor to the front fender, and grabs the front fender at the same time.
Wadded Up: A bad looking crash.
Washed Out: Front tire slides out to one side or the other.
Water Pump: 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: Officials apply water to the track so the track doesn’t dry out. This makes the terrain tackier to create better traction for racers.
Wheelie: When a rider accelerates and the front wheel lifts up off of the ground.
Whip: Rider lays the bike flat horizontally in the air and then brings it back up for the landing.
White flag: One lap to go until finish.
Whoops: Mogul-like section of the track typically consisting of more than 10 tiny jumps in a row.
Wide open: Top speed of each gear on a motorcycle or the top speed the motorcycle can go. Wrist pin: Holds the piston onto the crankshaft.
Yellow flag: Caution. When a yellow flag is displayed, competitors must ride cautiously until they have passed the incident that caused the flag. In motocross when a yellow flag is displayed there is no passing or jumping between the flag and the incident that caused the yellow flag. Failure to do so may result in the rider being docked from one finishing position all the way to disqualification from the event subject to the referee’s discretion.