Stem Length and Rise Are Measured Separately
A bicycle stem has two measurements: length and rise (also called angle or reach). Length runs from the center of the steerer tube clamp to the center of the handlebar clamp, measured in millimeters. Rise is the angle at which the stem points upward, measured in degrees from horizontal, or sometimes as a vertical height in millimeters. You need both numbers to order a replacement or understand what you have.
Most stems come in length increments of 10 mm — 60 mm, 70 mm, 80 mm, 90 mm, 100 mm, 110 mm, 120 mm — though some brands make 5 mm steps. Rise angles are typically 0°, 6°, 10°, 17°, or 25°, with 0° being completely horizontal and 25° pointing noticeably upward. A few manufacturers list rise as a vertical measurement instead (for example, 20 mm of rise rather than 10°), so check the spec sheet to know which system the brand uses.
Key Takeaways
- Stem length is measured in millimeters from the center of the steerer tube clamp to the center of the handlebar clamp, and most stems come in 10 mm increments between 60 mm and 130 mm.
- Stem rise is the upward angle of the stem, expressed either as degrees (0° to 25°) or as vertical millimeters, and affects how high your handlebars sit relative to the saddle.
- You can measure an installed stem with a ruler and protractor, or you can look up the model number on the manufacturer's website to find the exact specs.
- Changing stem length shifts your reach forward or backward, while changing rise adjusts handlebar height without moving the bike's geometry.
How to Measure Stem Length With a Ruler
Place a ruler or measuring tape along the top of the stem, starting at the center of the steerer tube clamp (where the stem grips the fork) and ending at the center of the handlebar clamp (where the handlebars sit). The steerer tube clamp is the vertical part that slides onto your fork; the handlebar clamp is the horizontal part at the end. Measure to the middle of each clamp, not the edges.
If your stem is installed, you may need to loosen the handlebar clamp bolts slightly so you can slide the ruler underneath without moving anything. Do not remove the bolts entirely — just loosen them enough to fit the ruler. Write down the measurement in millimeters. If your ruler only shows inches, multiply by 25.4 to convert to millimeters, or measure twice to be sure.
Some stems have a slight curve or bend, which can make the measurement tricky. Measure along the centerline of the stem (the imaginary line running through the middle), not along the top or bottom edge. If the stem is very curved, a flexible measuring tape works better than a rigid ruler.
How to Measure Stem Rise With a Protractor
Stem rise is the angle between the stem and a horizontal line. To measure it, place a protractor against the top of the stem so that the 0° line aligns with horizontal (use a level or a straight edge held horizontally for reference). Read the angle where the stem points. Most stems angle upward, so you will read a number between 0° and 25°.
If you do not have a protractor, you can estimate rise by eye: a 0° stem points straight ahead, a 10° stem points noticeably upward, and a 25° stem points steeply up. For a more precise measurement without a protractor, measure the vertical height of the stem at two points along its length, then use a calculator to find the angle — but this is more work than it is worth for most riders.
If your stem is installed and you cannot remove it easily, take a photo from the side and use a smartphone protractor app, which uses your phone's built-in level to measure angles. Lay the phone along the stem and read the angle from the app.
Finding the Specs on Your Current Stem
The easiest way to learn your stem's measurements is to look them up. Most stems have a brand name and model printed on the side — common brands include Specialized, Trek, Giant, FSA, Ritchey, and Deda. Search the brand's website for "[brand name] [model number] specs" and you will find a page listing the length and rise.
If the model number is worn off or unclear, take a photo of the stem and email it to the bike shop where you bought the bike, or post it on a cycling forum. Experienced riders can often identify a stem from a photo. You can also measure the stem yourself using the methods above — it takes five minutes and is more reliable than guessing.
If you bought the bike used and have no paperwork, the original receipt or spec sheet may be on the manufacturer's website under the bike's model year and size. Search "[bike brand] [year] [size] geometry" and look for the stem length in the parts list.
Understanding Stem Length and Handlebar Reach
Stem length controls how far forward your handlebars sit from the steerer tube. A 60 mm stem is short and brings the bars closer to you; a 120 mm stem is long and pushes them farther away. Changing stem length changes your reach — the horizontal distance from the saddle to the handlebars — which affects your riding position and comfort.
Shorter stems (60–80 mm) are common on mountain bikes and upright commuters because they keep the bars closer and make the bike more responsive to steering input. Longer stems (100–130 mm) are common on road bikes and gravel bikes because they stretch the rider into a more aerodynamic position. Most hybrid and comfort bikes use 80–100 mm stems as a middle ground.
If your current stem feels too long or too short, you can swap it for a different length without changing any other parts. A shorter stem makes the bike feel snappier and brings your weight more over the front wheel; a longer stem makes the bike feel more stable and stretches your upper body out. The right length depends on your arm length, torso length, and riding style.
Understanding Stem Rise and Handlebar Height
Stem rise controls the angle at which your handlebars point upward. A 0° stem is horizontal and keeps the bars low; a 25° stem angles steeply upward and raises the bars without changing the stem length. Rise is useful when you want to adjust handlebar height without buying a longer or shorter stem.
Upright bikes and comfort bikes often use stems with 17° to 25° rise to keep the bars high and the rider sitting upright. Road bikes typically use 0° to 6° rise to keep the bars low and the rider in a forward-leaning position. Mountain bikes vary depending on the style — cross-country bikes use low rise, while trail and enduro bikes often use higher rise for a more upright posture.
If you want to raise your handlebars without buying a new stem, you can swap to a stem with more rise. If you want to lower them, you can swap to a stem with less rise. Some riders also use a headset spacer (a thin ring that sits under the stem on the steerer tube) to raise the bars slightly without changing the stem itself, though this is a smaller adjustment than changing rise.
Common Stem Sizes and What They Fit
Stems come in two steerer tube sizes: 1 1/8 inch (standard on most modern bikes) and 1 1/4 inch (common on larger mountain bikes and some older road bikes). You must match the steerer tube size or the stem will not fit. Check your fork's steerer tube diameter before ordering a replacement stem.
Handlebar clamp sizes also vary: 25.4 mm (1 inch, older standard), 26.0 mm (less common), and 31.8 mm (modern standard on most bikes). Your new stem must match your handlebar diameter. If you are unsure, measure the handlebar diameter with calipers or a ruler, or ask your bike shop.
A typical road bike uses a 1 1/8 inch steerer tube, 31.8 mm handlebar clamp, 80–100 mm length, and 0–10° rise. A typical mountain bike uses a 1 1/8 inch steerer tube, 31.8 mm handlebar clamp, 50–70 mm length, and 0–17° rise. A typical commuter or hybrid uses a 1 1/8 inch steerer tube, 31.8 mm handlebar clamp, 80–100 mm length, and 10–25° rise. Always check your current stem and fork before buying a replacement.
Frequently Asked Questions
What is the difference between stem length and reach?
Stem length is the measurement of the stem itself, from the steerer tube clamp to the handlebar clamp. Reach is the horizontal distance from your saddle to your handlebars, which is affected by stem length, frame size, and frame geometry. A longer stem increases reach; a shorter stem decreases it.
Can I measure a stem that is still attached to the bike?
Yes. Loosen the handlebar clamp bolts slightly and slide a ruler underneath to measure length. For rise, use a protractor or a smartphone level app held against the stem. You do not need to remove the stem to measure it.
What happens if I buy a stem that is too long or too short?
A stem that is too long stretches you forward and can cause back and shoulder pain; a stem that is too short brings the bars too close and can feel cramped. You can swap stems easily without tools other than an Allen wrench, so if the new stem does not feel right, you can try a different length.
Do I need to match the rise angle of my old stem?
No. You can change rise independently of length. If you want to raise your bars, buy a stem with more rise. If you want to lower them, buy a stem with less rise. Many riders experiment with different rise angles to find the most comfortable position.
Where do I find the model number on my stem?
The brand name and model are usually printed or engraved on the side of the stem, near the handlebar clamp or the steerer tube clamp. If the text is worn off, take a photo and search for similar-looking stems online, or ask a bike shop to identify it.