New to cycling and drowning in jargon? This glossary explains the essential bike terms in plain English, grouped by topic so you can find what you need fast. Bookmark it — it's the cheat sheet every new rider wishes they had.
Frame and fit
Frame — the main structure of the bike that everything else attaches to.
Head tube — the front tube that holds the fork and steering.
Down tube — the large tube running from the head tube to the pedals; the most stone-chipped part.
Top tube — the horizontal tube between the saddle and handlebars.
Chainstay — the tube running from the pedals to the rear wheel; takes the brunt of chain slap.
Seatstay — the tube from the saddle area to the rear wheel.
Bottom bracket (BB) — the bearing assembly the cranks rotate on.
Fork — the part holding the front wheel; may include suspension.
Geometry — the frame's angles and lengths, which determine how a bike handles and fits.
Hardtail — a mountain bike with front suspension only, no rear shock.
Full suspension — a mountain bike with both front and rear suspension.
Drivetrain
Drivetrain — all the parts that transfer your pedalling to the wheel: chain, cassette, chainrings, derailleurs.
Groupset — the matched set of drivetrain and brake components from one maker.
Cassette — the cluster of gears (sprockets) on the rear wheel.
Chainring — the front gear(s) attached to the cranks.
Crankset — the arms and chainrings your pedals attach to.
Derailleur — the mechanism that moves the chain between gears (front and rear).
Cadence — how fast you pedal, in revolutions per minute (RPM).
Gear ratio — the relationship between front and rear gears that sets how hard or easy pedalling feels.
Quick link — a removable chain link that lets you split and rejoin the chain without a tool.
Chain wear — the elongation of a chain as its parts wear; replace it before it damages the cassette. See when to replace your chain.
Wheels and tyres
Rim — the outer hoop of the wheel that the tyre sits on.
Hub — the centre of the wheel containing the bearings.
Spokes — the wires connecting hub to rim.
Clincher — the common tyre type that uses an inner tube.
Tubeless — a tyre that seals to the rim with no tube, using liquid sealant. See our tubeless setup guide.
Sealant — liquid inside a tubeless tyre that plugs small punctures automatically.
Presta valve — a thin valve with a locking nut, common on road bikes.
Schrader valve — the fat car-style valve, common on hybrids.
PSI — pounds per square inch, the unit of tyre pressure. See our tyre pressure guide.
Pinch flat — a puncture caused by the tube being squeezed against the rim on an impact.
Brakes
Rim brakes — brakes that squeeze pads against the wheel rim.
Disc brakes — brakes that clamp a rotor at the hub; more powerful in the wet. Can be hydraulic or mechanical.
Rotor — the metal disc a disc brake grips.
Brake pads — the friction surfaces that wear and need replacing.
Riding disciplines
Road cycling — riding fast on paved roads with drop-bar bikes.
MTB (mountain biking) — off-road riding on trails. See MTB vs gravel vs road.
Gravel — mixed-surface riding on a drop-bar bike with wider tyres.
Bikepacking — self-supported multi-day riding with gear in soft bags. See our bikepacking guide.
Cross-country (XC) — fast, endurance-focused mountain biking.
Enduro — mountain biking focused on technical, descending-heavy trails.
Bonk — running out of energy mid-ride; avoided by fuelling properly. See our fuelling guide.
Accessories and gear
Bidon — a cycling water bottle.
Saddle bag — a small bag under the seat for spares and tools.
Frame bag — a bag that fits in the frame triangle for larger loads.
Top tube bag — a bag on the top tube for quick-access snacks and your phone.
Mudguard / fender — a guard that blocks road spray in the wet.
PPF (paint protection film) — clear film that protects the frame from chips and rub. See Frame Protection 101.
Chainstay protector — a cover that absorbs chain slap and reduces rattle.
Maintenance terms
Degreaser — a cleaner that removes greasy grime from the drivetrain.
Wet lube — a sticky chain lube for wet conditions.
Dry lube — a cleaner-running chain lube for dry, dusty conditions.
Torque wrench — a tool that tightens bolts to an exact spec, important on carbon.
Chain checker — a gauge that measures chain wear so you replace it on time.
Frequently asked questions
What is the difference between a clincher and a tubeless tyre?
A clincher uses an inner tube; a tubeless tyre seals to the rim with no tube and uses liquid sealant to plug small punctures.
What does cadence mean in cycling?
Cadence is how fast you pedal, measured in revolutions per minute. A smooth, higher cadence is usually more efficient than grinding a big gear.
What is a groupset?
A groupset is the matched collection of drivetrain and brake parts — shifters, derailleurs, cassette, chain, cranks, and brakes — from a single manufacturer.
What does "bonk" mean?
Bonking is running out of available energy during a ride. You prevent it by eating before you set off and fuelling regularly while riding.
Keep learning
Now that the jargon makes sense, put it to use: dial in your tyre pressure, learn to fix a flat, and protect your bike with frame protection and the right bags.