Hub - the central component of a wheel inside the hub are the axle and ball bearings. Headset - the collection of bearings housed within the head tube of the bike frame it provides smooth steering. Both the gears and the coasting mechanism are part of the freewheel component, as opposed to cassette gears, where the gears are a solid, non-moving component, and the coasting mechanism is part of the wheel's hub. The cassette is attached to the freehub body.įreewheel - the collection of gears attached to the rear wheel found on mostly older bicycles and some lower-end modern bicycles. A frame and fork sold as a combination are referred to as a frameset.įreehub body - a part of the hub on most rear wheels, it provides that coasting mechanism that transfers power to your wheel when you are pedaling forward, but allows the rear wheel to turn freely when you are pedaling backwards or not pedaling at all. Composed of a top tube, head tube, down tube, bottom bracket shell, seat tube, seat stays, and chain stays (see image). The steerer tube is a part of the fork that extends up into the frame through the head tube.įrame - the main structural part of the bicycle, commonly made of steel, aluminum, titanium, or carbon fiber. "Fixie" for short.įlat bar - a handlebar with little or no upward or downward curve some flat bars will have a slight backward curve, or "sweep."įork - the two-legged part of the frame that holds the front wheel in place. If the wheels are moving, you have to be pedaling. So-called because if you loosen the bolts holding a wheel in place, the wheel "drops out."įixed gear - a type of bicycle that has a single gear and does not have a freewheel or cassette/freehub mechanism, so you are unable to coast. It is usually an integrated part of the frame on steel and titanium bikes, but is a separate, replaceable piece on aluminum and carbon fiber bikes.ĭrop bar - the type of handlebar found on road racing bikes, with the half-circle-shaped curved ends that extend below the top, flatter part of the bar.ĭropouts - the U-shaped notches at the rear of the bike frame, and at the bottom ends of the front fork legs, where the wheels are held in place. The rear derailer handles the shifting on your cassette or freewheel, and is usually controlled by your right-hand shifter.ĭerailer hanger - a part of the frame where the rear derailleur is attached. The front derailer handles the shifting on your chainrings and is usually controlled by your left-hand shifter. A bike with two chainrings is said to have a "double crank " a bike with three chainrings is said to have a "triple crank."Ĭog - a single gear on a cassette or freewheel gear cluster, or the single rear gear on a fixed-gear bike.Ĭrank arms - the pedals screw into these these bolt onto the bottom bracket spindle.Ĭyclocomputer - the preferred fancy word for an electronic speedometer/odometer.ĭerailer - the device that is bolted to the frame that handles the job of moving the chain from one gear to another when you shift gears. Scroll down to the bottom of this page for a video overview of most major bike parts.īar ends - the angled extensions attached to the ends of some flat handlebars and riser handlebars that provide an alternate place to rest your hands.īottom bracket - the collection of ball bearings and spindle housed within the bottom bracket shell of the frame, which provides the "shaft" mechanism on which the crank arms turn.īraze-ons - threaded sockets that may or may not be present on the bike frame that provide a place to attach accessories such as bottle cages, cargo racks, and fenders.Ĭage - the preferred fancy name for water bottle holder.Ĭassette - the collection of gears that is attached to the rear wheel on most modern bicycles (see "Freewheel").Ĭhainrings - the gears that are attached to the right-hand crank arm nearer to the front of the bike. To that end, here is a glossary providing a breakdown of the anatomy of the bicycle. So, breaking down the language barrier is an important step in productive relationships between bike shop customers and bike shop employees. On the other hand, we've gotten really perplexed looks when we've handed somebody a "rim," when they were really looking for an entire wheel. For example, we sometimes get people asking for a "wheel," when all they really need is a new tire. We have to really ask questions to make sure we're on the same page with a customer and really understand what they are looking for, and often it's just a matter of making sure we agree on the meaning of the words we are using. It's almost as bad as trying to pick out a personal computer!įrom our perspective, sometimes it's hard to tell when we're using everyday language and when we're slipping into technical jargon. Buying a new bike or accessories can often be bewildering to the novice the folks working in the shop almost seem to be speaking a different language.