Fillet Brazing
Summary Fillet brazing is a bicycle framebuilding technique in which mitered metal tubes are joined directly with brazing filler built into an external fillet rather than with structural…
Velopedia Entries
An evolving encyclopedia of cycling brands, technologies, components, and history.
TIG Welding
Summary TIG welding is a fusion-welding process that creates an electric arc between a non-consumable tungsten electrode and the workpiece. In bicycle manufacturing, TIG—formally Gas Tungsten Arc Welding…
Brazing
Summary Brazing is a metal-joining process in which a filler metal is melted and used to join components without melting the base metals themselves. In bicycle construction, brazing…
Tube-to-Tube Construction
Summary Tube-to-tube construction is a framebuilding method in which separately manufactured tubes are cut, aligned, and structurally joined to form a bicycle frame. Although virtually all traditional metal…
Monocoque Frame
Summary A monocoque frame is a bicycle frame whose thin-walled outer structure carries the primary structural loads rather than relying on a separate internal skeleton. The term is…
Void Content
Summary Void content is the proportion of microscopic empty spaces within a composite laminate, usually expressed as a percentage by volume. In carbon-fiber bicycle frames and components, excessive…
Clutch Derailleur
Summary A clutch derailleur is a rear derailleur with a chain-stabilizing mechanism that resists unwanted cage rotation. By controlling movement in the lower chain span, it reduces chain…
Derailleur Hanger
Summary A derailleur hanger is the interface that positions a conventional rear derailleur relative to the bicycle frame and cassette. On most modern bicycles it is a separate,…
Derailleur
Summary A derailleur is a bicycle drivetrain component that moves the chain between sprockets or chainrings to select different gear ratios. Rear derailleurs also maintain chain tension as…
Bosch
Summary Bosch is a German engineering and technology company whose Bosch eBike Systems division develops integrated electric bicycle drive systems. Best known for mid-drive motors, Bosch combines drive…
Hub Spacing
Summary Hub spacing is the width of a bicycle hub at the surfaces that contact the frame or fork dropouts. Traditionally called over-locknut dimension (OLD), it is a…
Hub Flange Spacing
Summary Hub flange spacing is the lateral distance between the spoke flanges of a bicycle hub. Together with each flange’s position relative to the wheel centerline, it determines…