In the early 1980s comedian and keen cyclist Alexei Sayle gave an interview to Bicyclemagazine in which he talked about the way bike shops guard their knowledge with language. “You ask for a hub,” he said, “and they reply ‘cross-threaded or off-flange?’ and then they’ve got you!”
Cycling’s technical jargon is one of the biggest hurdles when you’re starting out, so here’s a glossary of terms to help you out.
Alloy: A mixture of one or more metals and other elements. Alloying changes the physical properties of the main metal. For example, the common 6061 aluminium alloy used for bike frames contains magnesium and silicon and has a yield strength roughly thirty times higher than pure aluminium.
Aluminium: Low-density metal used in various alloys for bike frames and components.
Anti-seize: Grease containing very fine metal particles, used to stop threaded parts from corroding together.
Bead seat diameter: Diameter of the tyre bead.
Bead seat: The part of the rim where the tyre bead sits. The diameter of the bead seat is the basis of rim and tyre size standards. For example the standard road bike wheel and tyre size, 700C, has a bead seat diameter of 622mm
Bead: see Tyre bead.
Bearing: Any mechanism that reduces friction to allow parts to move easily against each other. Most common bicycle bearings use steel balls to allow parts to turn easily. Plain bearings, also known as bushings, have low-friction surfaces that slide against each other and are found in some components such as pedals and jockey wheels
Bimetallic corrosion: Aka galvanic corrosion; this is corrosion damage caused by a chemical reaction between two dissimilar metal surfaces and salt water. The most common example is aluminium seat posts corroding in place in steel frames because of the constant washing in salt water this area gets in a British winter.