Sierra Blogging Post Archives

Decided to rack up some road miles this spring? Thinking about joining your friends on the singletrack when the snow melts?

If you'll be purchasing a mountain bike or road bike this year, it pays to make an informed decision. There's much more than meets the eye when it comes to the precision machinery of a bicycle.

The basic knowledge in the Bike Anatomy Guide will make your bike shopping experience all the more comfortable... like sitting on a well-padded saddle.



Here's an excerpt from the Bike Anatomy Guide:

Frame Set

The frame is the skeleton of the bike. A bike frame generally consists of one large “triangle” made up of three tubes (the top tube, down tube and seat tube), plus two smaller pairs of bars (the seat stays and chain stays ) that link the back wheel to the seat tube to form a second triangle. Another metal tube, called the head tube, is attached where the top tube and down tube meet and houses the headset.

This paired-triangle frame design is called a “diamond frame.” The tube sections making up these triangles are smooth and cylindrical on most bikes, but may also be angular or octagonal in a cross section (called “hydroformed” tubes).

The “geometry” of a bicycle is a set of specifications mostly taken from the lengths of the various tubes and the angles between them. This geometry will differ depending on the type of bike. For example, the handlebars on a road bike are set low and far away from the seat to enable the rider to get into the most aerodynamic position possible. Conversely, the handlebars on an MTB, commuter or cruiser are set higher and closer to the body for a comfortable, upright ride.

Frames may be made from steel, aluminum alloys, titanium or carbon fiber. The material type significantly affects the weight of the bicycle.

Shop Bicycles and Bike Frames

Read the rest of the Bike Anatomy Guide.