Updated: 26th Sep 2007
Bike related words and abbreviations. This is not intended as a deinitive list and shall remain a work in progress, i hope it proves useful.
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
A
Allen Bolt - Bolt or screw with a hexagonal hole used for adjustment via an allen key or hex wrench.
B
Bar Tape - Used on handlebars to provide a good contact point for the hands, like grips.
BCD - Bolt Circle Diameter.
Bent - A Recumbent bicycle.
BMX - Bicycle Motocross.
Bottom Bracket - The bearings unit that are usually screwed into a frame to connects the pedal/crank arms together.
Brazing - Like welding but using brass.
BSD - Bead Seat Diameter.
Butted - Usually refers to the thickness of a tube or spoke which alters across it's length.
C
Cadence - The speed at which your feet rotate when pedalling.
Cassette - Multi speed geared sprocket found on the rear wheel that connects to the chainrings via the chain.
Chainstay - The bars of a bike frame that run from the bottom bracket to the center of the rear wheel.
Chainrings/Crankset - Gear cog/s connected to the bottom bracket and crank arms.
Cleat - A plate attached to a cycling shoe that connects to a suitable pedal.
Cotter - Bolt with a flat side usually used to connect the crank arms to the bottom bracket.
Crank Arms - The arms that connect the pedals to the bottom bracket.
D
Derailleur - Mechanism that is used to shift the chain up and down the rear cassette and chainrings.
Dish - Usually relates to the offset of a wheel to accomadate the width of the rear cassette.
Downtube - Bottom tube on the frame that connects the head tube to the bottom bracket.
Dropout - Slotted portion of the frame or fork that the wheel slots into.
E
English Standard - A common standard of sizes used for bike components.
ETRTO - European Tyre ∓ Rim Technical Organisation
F
FG - Fixed Gear.
Flanges - Outer part of a hub that the spokes connect to.
Fork Crown - The section that joins the fork blades to the steerer tube.
Frame - The main structure of the bike, commonly made of metal tubing.
Frameset - The frame and forks.
Freewheel - Connects the sprocket/s (or cassette) to the hub of the rear wheel and allows you to stop pedaling when the bike is in motion.
G
Gear Inches - Wheel Diameter (including tyre) x Chainring teeth / Sprocket teeth.
Grips - Used on handlebars to provide a good contact point for the hands, like bar tape.
H
Handlebar - Bar or tube that is connected to the stem and is used to steer the bike.
Headtube - The front tube of the frame that the steering tube goes through and top and down tubes connect to.
Hub - The center section of the wheel that the spokes connect to and the wheel axle goes through.
I
Inner tube - Rubber tube used betwen the rim and tyre which is inflated with air to reinforce the tyre structure..
Italian Standard - A standard of sizes used for bike components.
J
Junker - A bike of little monetary value or roughly put together.
L
LBS - Local Bike Shop.
Left-threaded - Thread that tightens (anti-clockwise) and loosens (clockwise) in the opposite direction to 'normal' threads.
Limit Screw - Limits the movement of the derailleur so that the chain doesn't fall off the chainring or sprocket.
Locknut - Nut used to retain other components on a threaded spindle.
M
MTB - Mountain Bike.
O
Odometer - Used to measure mileage, like a speedometer.
OLN - Over Lock Nut, distance between the inner faces of the dropouts.
P
Pawl - Moveable metal arm that engages a ratchet system, typically found in a freewheel.
Pedal - Where your feet interface with the bike.
Pedal Arms - The arms that connect the pedals to the bottom bracket, also referred to as Crank Arms.
Penny Farthing - Pre-gears bike that has a very large front and small rear wheel.
Presta Valve - Valve used on some bike innertubes that is thinner than the 'normal' Schraeder (car) valve.
P.S.I. - Pounds per Square Inch, inflation rating for innertubes and tyres.
Puncture - When a object has broken through the innertube/tyre and caused them to deflate.
Q
Quick Release - Securing mechanism that can be used by hand that does not require tools, often used to secure wheels and seat posts.
R
Randonneur - Type of handlebar.
Ratchet - Tooth surface that interacts with a pawl/s, as used in a freewheel.
Rim - The outer metal ring of a wheel which connects to the hub via spokes.
S
Schraeder Valve - Valve used on bike innertubes also used on car tyre valves.
Seatpost - Tube that connects the saddle/seat to the frame via the seattube.
Seatstays - The bars of a bike frame that run from the top of the seattube to the center of the rear wheel.
Seattube - Tube that houses the seatpost and also connects between the toptube, bottom bracket and seatstays.
Shifter - Mechanism used by the hands to change gear.
SPD - Shimano Pedaling Dynamics, common type of 'clipless' bicycle pedal.
Spokes - Thin (often metal) rods used to connect the wheel rim and hub together.
Spoke nipple - Small T shaped nut used to secure spokes to a rim.
Sprocket - Toothed cog (a collection of which is also called a cassette) found on the rear hub and used to connect to the chainring via the chain.
SS - Single Speed.
Steering Tube - Top section of the forks that is used to go through the headtube and connect the forks to the frame.
Stem - Used to connect the handlebars to the steering tube.
T
Toe-in - A method of angling brake blocks against the rim's breaking surface to stop them from squealing when the brake is applied.
Toeclips - Brackets/cages used to secure your feet to the pedals, often used in conjunction with toestraps.
Toestraps - Loop through your pedals and toeclips to secure your feet, often made of leather or nylon.
Toptube - Top tube on the frame that connects the headtube to the seattube.
Track Bike - Fixed, single geared bike, without brakes, that is mainly used for track riding.
Track Rod End - Similar to a dropout, but rear facing and usually found on track bikes.
Track Stand - A method of keeping a bike stationary and upright, without contacting the ground with your feet.
True - When something (usually a wheel) is perfectly straight.
Tyre - Circlular rubber hoop that comes into contact with the riding surface and houses the innertube onto the rim.
U
Unicycle - One wheel bike.
V
Valve - Found on innertubes in order to pump and keep air in, typical examples on bikes are Presta and Schraeder.
Velodrome - Home of a bicycle racing track, these are typically made of wood, oval and banked towards the outside edge.
W
Washer - Circular metal ring used betwen a nut and a component to spread surface load.
Workstand - Used to securely hold a bike for maintenance purposes.
Y
YMMV - Your Mileage May Vary.
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