The bike stem is part of your bike that connects the handlebars to the frame. It’s what lets you adjust how high or low you sit on your bike, which in turn affects how easy it is for you to pedal and brake. Stems come in different lengths and materials, so finding one that fits your needs should be a fun process.
What is a bike stem?
A bike stem is a tube that connects your handlebars to your frame. Stems are measured in length, with a typical size being either 100mm or 120mm. The shorter models allow riders to achieve more aggressive positions by lowering their center of gravity. In contrast, longer ones help them sit up straight and maintain more control over their bikes.
Stems can be made from aluminum, carbon fiber, steel (or even titanium). They’re attached to forks via bolts called “top caps”–one at each end of the stem–and feature clamping bolts known as quill stems that tighten down on fork steerers via different types of pinch bolts: threaded or threadless (more on those later).
The geometry of a bike stem
The stem is part of your bike that connects the handlebars to the frame. For this connection to be strong, it needs to withstand a lot of force–the force generated by pedaling and braking and any bumps in the road.
A bike stem is a tube that attaches your handlebars to the front fork of your bike. It allows you to adjust the height of your handlebars and keep them at a comfortable height for riding.
The angle of your steering column is determined by the angle of the headset, which is attached to the front fork compressing it against the head tube. The head tube is connected to both sides of the fork which means that when you turn one way or another, it will cause one side of the fork to compress while the other side expands.
The stem has three different parts: The steerer tube (which connects your headset and frame), The extension (which connects your handlebar and steerer tube), And finally, The clamp (which connects between extension and handlebar).
Types of Stems
There are two main types of stems: quill and threadless.
Quill stems, the original standard (and still used in some places), require a threaded steerer tube on the bike’s frame that has been pre-cut to fit one threadless or quill stem. The rider then screws their chosen handlebar into this pre-cut hole at an angle, which can cause problems with shifting if they aren’t careful–not only is it challenging to get your gears lined up properly when you’re doing it by feeling alone but there’s also no way of knowing whether your shifting will be affected until you’ve finished mounting everything up and hit the road!
Threadless systems are much easier to install because there’s no need for any cutting or drilling; instead of threading directly into the headset itself like quills do, they clamp onto an internal nut inside said headset via small hex bolts on either side (these nuts are called “expanders”). This allows manufacturers flexibility when designing new bikes without having to worry about compatibility issues between older models’ stems and newer ones’ headsets–and makes changing out handlebars easier too since all you have to do is loosen those bolts slightly before pulling everything apart again.
How to choose the best stem length
Now that you have the basics down, let’s talk about how to choose the best stem length for your bike and riding style:
- Start with the right size frame The best way to find the right stem size for your bike is to start with the correct frame size. A stem that’s too short will make it harder for you to reach the handlebars comfortably and may interfere with other components like disc brakes, fenders, racks, or bottle cages.
- Adjust seat height – Next, adjust your seat height so that you can comfortably reach the handlebars from a standing position -This will help ensure that you have enough room in front of the stem for your hands to move back and forth without hitting anything.
- Adjust handlebar height – The next step is to adjust the handlebar height so that you can comfortably reach the handlebars from a standing position. If your bike does not have adjustable handlebars, you may need to replace them with ones that do. The stem should be roughly level with the seat post when in this position.
- Adjust stem length – If you’re using a stem, the next step is to adjust its length so that it is roughly level with the seat post when in this position. The handlebars should be at a comfortable height and angle for you when riding.
How to measure stem length
The first thing to do when measuring your stem length is to ensure that you measure from the bottom bracket. The bottom shelf is part of your bike frame where all of its gears are housed and connected, so this will ensure that your measurements are accurate.
Next, look at how far away from the handlebars (and thus wheels) does it sit? This distance will tell us how high or low our front wheel needs to be when we put on our new stem for everything else about our bike setup not to change too much; ideally we want it as close as possible without interfering with any other components like brakes or mirrors!
Finally, measure from the center of the bottom bracket up through the top tube – this gives us some perspective on how long or short our new component will make things look overall while helping us decide whether we should go with something shorter or longer than the stock specs might suggest based solely upon height alone.”
The Bottom Line
The bike stem is an essential part of your bike. It’s what connects the handlebars to the fork and allows you to adjust their position. Stems come in various shapes and sizes, so it’s essential to choose one that fits your needs as well as possible. The length of the stem should be measured from where it attaches directly under the handlebar clamp area (where it attaches onto the frame) up until where it meets with your head tube at its widest point (which should also correspond).