GENERAL TERMINOLOGY OF BICYCLE PARTS - ifixie

Chapter on individual component areas of the bicycle have more specific terminology and definitions. For the purpose of this manual, the following terms apply to the frame and basic components.

Frame : The structural piece, usually a number of tubes joined together, to which all of the components are attached.
Fork : The structural piece that attaches the frame to the front wheel. The fork turns to allow the rider to control the bicycle.
Frame set : The frame and fork combination.
Head Tube : The near-vertical tube that is the forward most past of the frame.
Top Tube : The upper tube of the frame that extends back from the head tube to the seat tube.
Down Tube : The lower tube of the frame that extends the bottom of the head tube to the bottom of the framr (the bottom-bracket shell).
Seat Tube : The near-vertical tube that is at the middle of the frame, which the seat post slides into.
Bottom-bracket Shell : The portion of the frame that contains the crankset bearing parts, which are called the bottom bracket.
Seat Stay : The two tubes of the frame that start from below the seat and meet the chain stays at the center of the rear wheel.
Chain stay : The two tubes of the frame that go from the lower end of the seat tube and meet the seat stays at the center of the rear wheel.
Drop Out : The fittings at the end of the fork and at the juncture of the seat stays and the chain stays, to which the weel are attached.

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