What are bike stems?
A bike stem is simply the piece that attaches the steering tube of the bicycle fork to the handlebars. The bike stem is also referred to as the goose neck.
Why are bike stems important?
The bike stem is another essential piece to the construction of the bicycle. The stem provides the fundamental for the steering tube and the handlebars to be held together. This in turn allows the rider to steer his bicycle.
How do bicycle stems work on a bike?
Bicycle stems are made of aluminum, carbon fiber, steel and titanium. Bicycle stems are attached by being tightened onto the handlebars by using pinch bolts or faceplates. A stem can come in two different types of dimensions. These lengths are an angle, forward length or an extension. Some bicycles require certain stem dimensions for compatibility.
How do you choose the right bike stem for your bike?
Compatibility, compatibility, compatibility—this is what you need to remember. Your bike needs to have all compatible parts. If you do not succeed in doing such, you bike will either not work at all or not perform at its best. When looking at bike stems it is important to know whether you need a quill (threaded) or a threadless stem. Threadless stems are defined by the headset lock nut threading into the fork steer tube. Quill (threaded) is defined by a threaded headset with specific lengths. For quill type stems there needs to be certain lengths of the steerer tubes and forks. The quill stem is an older type of stem. The most common stem found today is the threadless. Threadless stems are easier to remove, repair, and replace. The quill requires a lot more work to remove.
A quill stem slides into the the top of the steerer fork tube. Then the stem is held into place by means of a wedge & bolt or a cone expander nut & bolt. The steerer tube does not go above the headset, when using a quill stem. Then the threaded fork extends up and through the headset.
Threadless stem parts attach around the outside of the steerer tube and reaches above the headset. Then the star nut is screwed in to hold the stem and the steerer tube in place.