How to Measure Stem Length
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If you’re reading this, then you want to learn how to measure stem length. To start with, it’s important to understand what the bike stem is.
Basically, it’s the part of your bike that’s utilized to attach the handlebars to the bike. Bike stem measurement is important because it plays a huge role in your riding experience, particularly its comfort and performance. That’s because the bike stem determines your steering level.
The higher the stem the harder or easier it can be for you to ride your bike depending on your height as well as other variables such as the terrain and distance traveled. However, it’s important to learn how to measure stem length in order to ensure that the stem is the right length so that you can avoid arm fatigue. It can really put a damper on your ride.
You want your handlebars to have a fair amount of space between them to prevent stress on the upper body. They shouldn’t be too low either, or else, you’ll be forced to assume a more forward stance with your torso.
The good news is that learning how to measure a bike stem is a pretty straightforward process. We’re going to show you how to measure bicycle stems on two of the most popular types of bike models, including the mountain bike and the road bike.
Things You Need
Before you learn how to measure a bicycle stem, you need the following:
- Piece of paper
- Calculator
- Pen or pencil
- Flexible tape measure that’s set in centimeters
How to Measure a Bike’s Stem Length
How are bike stems measured? In millimeters, ideally. To measure the quill stem, you have to start from the center of the handlebars and go up to the middle of the clamp section of the handlebars.
To measure the threadless stem, you start from the middle of the steerer tube opening all the way to the middle of the handlebars.
Stand on Even Ground
The first step to learning how to measure bike stem length is to make sure that you’re standing on even ground while keeping your feet two inches apart.
Take the tape measure and position it downwards from the groin while facing the surface to measure the inseam. Write down the number that you get on your piece of paper.
Measure Body Length
Next, you need to measure your body’s length starting from the notch directly underneath your throat all the way to the ground.
If you have a bit of a belly bump, then you should get a pen and hold it horizontally to the sternal notch in order to get a straight line. Right down the number that you get on your piece of paper.
Check the Inseam Length
Once you know what the length of your body is, subtract the inseam length number from that to get the value of your torso. Write it down.
Measure the Inseam
Hold your arm out in order to measure your inseam and then bend your elbow at a 45-degree angle from your side.
Start measuring from the big bone on the outside of your wrist to the start of your joint. Write down the number that you get.
Add the Numbers
The next step in learning how to measure bicycle stem length is to add your arm length to the length of your torso. Write down the resulting number.
Consider Your Riding Style
Next, you need to determine what your riding style is. For instance, if you mainly use your bike for cruising and the daily commute then you’re a casual bike rider.
But, if you use your bike to do sprints and go on long rugged mountain trails, then it’s safe to say that you’re an aggressive bike rider. There’s also a mid-range biker for those who don’t fit in either category.
Figure Out the Ideal Stem Length
Now, take your riding style and multiply it by the arm-plus-torso length in order to determine your ideal stem length, preferably in centimeters.
The Last Touch
Once you’ve got your ideal length, multiply it by 100 in order to get its value in millimeters.
Ask a friend to help you get an objective answer for your stem length. It’s important to ensure that your body measurements are in centimeters because road bike measurements will be in metric.
If the measuring tape that you’re using is in inches, it’s possible to convert its value to centimeters simply by dividing inches by 2.54. It’s a pretty straightforward process actually.
Final Thoughts
If you’ve made it this far, then you know how bicycle stems are measured.
You also know that it’s important to learn how to measure stem length so that you can enjoy a comfortable ride free from shoulder pain or neck discomfort.
You want your bike stem to be suitable for your body and riding style. It’s the key to success! From there, you can enjoy your bike rides and all the exercise, convenience, and happiness that they provide.
James Mattis
James is a passionate bicyclist who has done about every kind of biking there is. He loves the wind in his hair, the sun over his shoulder and maybe even the bugs in his teeth. No, just kidding about that last item. He isn’t crazy about road burns, either, but acknowledges that to have the good there is the occasional tumble. James feels that his bike is the place where he can unwind, leave troubles alongside the road, meet new people, go new places, and live the life of adventure that he loves. He is ready to share the ride with you.
