If you’ve been wondering how to measure bike handlebars, you’ve come to the right place.
In this short guide, I’ll teach you all of the handlebar measurements you need to know about and how to take each one of them accurately.
To make things easier for you, I’ve separated the guide into two main sections:
If you want to get straight to the action, choose your handlebar type above, and it’ll take you to the corresponding handlebar sizing guide.
Otherwise, just below, I explain the basics of handlebar sizing & why this procedure is so important.
I’d recommend reading the whole lot, as the information below will help you better understand bike handlebar sizes.
Why Choosing the Right Size Handlebars Is Important
You’d be surprised by how many cyclists never once think about replacing their handlebars. Blissfully unaware of what they’re missing out on.
By selecting the ideal pair of handlebars for your riding style, bike and body type, you stand to benefit from increased comfort, speed and control while cycling.
A poorly sized pair of bike handlebars can place unnecessary pressure on and strain your body.
By learning how to measure your bike handlebars correctly, you’ll be able to get rid of those niggling pressure pains you have when using your current handlebars.
Additionally, if you don’t know how to measure handlebars correctly, you’ll probably end up buying a pair of handlebars that aren’t compatible with your bike.
You might not even be in the market for new handlebars and may want to measure the size of your current handlebars.
Whatever the reason, keep reading, and I’ll show you the easiest way to measure the handlebars of any bike.
Choosing the Right Type of Handlebars for Your Bike
If you find your current handlebars uncomfortable or unsuitable for your cycling goals, it’s worth considering a different handlebar type.
Different pairs of handlebars support different riding styles. Many even provide multiple hand positions for reducing the strain on your body whilst cycling.
If you have any doubts about your current handlebar configuration, I’ve put together a quickfire handlebar type guide that will talk you through all of the different handlebar types available to you.
Read it here and learn the benefits and setbacks of each handlebar type.
Bike Handlebar Size Guide
As stated above, throughout this article, I’ll explain how to take the required measurements for both mountain and road bike handlebars.
At the bottom of the article, I explain how to measure handlebar diameter and answer the most popular FAQs on how to measure bike handlebars.
Now that we’ve covered all of the basics, it’s time for your handlebar sizing masterclass!
How to Measure Mountain Bike Handlebars
As I covered above, a poorly sized pair of handlebars can hold you back in terms of performance.
A narrow pair of mountain bike handlebars will reduce your steering capabilities and control on technical trails.
To begin with, we’ll learn how to choose the ideal mountain bike handlebar width.
1. Handlebar Width
The width of mountain bike handlebars is a commonly discussed topic in the cycling community.
It’s well known that wider handlebars will provide more accurate and responsive steering whilst opening up the chest for easier breathing.
On the other hand, narrow mountain bike handlebars are better for narrow trails and open up your shoulders and back, reducing fatigue and improving aerodynamics on rolling sections.
So which is better for you?
As much as I wish I could, I’d be lying if I told you there was a one-size-fits-all solution to handlebar width that suited every mountain biker.
Your ideal mountain bike handlebar width will ultimately depend upon your riding style, chosen MTB discipline and body shape (height and shoulder width)
The average width for mountain bike handlebars sits between 700 – 780mm. Whilst taller and heavier riders with broader shoulders choose to use mountain bike handlebars up to 800mm wide.
Ultimately, mountain bike handlebar width is subjective and will come down to personal preference.
Whilst there isn’t a one size fits all solution, there’s a calculation that you can use to determine the recommended max-width for mountain bike handlebars.
The max handlebar width calculation is as follows: Height (cm) x 4.4 = max handlebar width.
Alternatively, one of the best ways to determine the best width for your MTB handlebars is through trial and error.
Purchase a wide set of mountain bike handlebars and then gradually trim them down until you end up at the perfect size.
To avoid disappointment, move your grips and controls inwards on your bars, imitating the desired width and ride and re-adjust them before cutting your bars down.
Trialling a new bar width will allow your to accurately fine-tune your bar width before cutting, ensuring you find the most suitable width for you.
How To Measure Mountain Bike Handlebar Width
Unlike some other handlebar types, measuring the width of mountain bike handlebars is straightforward.
All you’ll need is a tape measure to take an accurate measurement.
- Place and hold one end of the tape measure on the end of your mountain bike handlebars.
- Pull the tape along the handlebar towards the other end and take the reading where the handlebar finishes in mm.
- This measurement is the handlebar width.
2. Handlebar Sweep
Upsweep and backsweep are two terms used to describe the geometry of a pair of handlebars.
Upsweep describes the angle at which handlebars protrude from their clamp area.
Upsweep is similar to handlebar rise, but the grip area of bars with upsweep is angled to provide a slightly more comfortable riding position for the wrist.
Backsweep is the angle at which handlebars bend back towards the rider. Like upsweep, backsweep provides increased wrist comfort whilst riding.
To measure both upsweep and backsweep you’ll need:
- Your Handlebars
- A pencil
- A ruler
- A protractor
How to Measure MTB Handlebar Upsweep
- Lay your handlebars on top of the piece of paper (front down), holding them at the angle you’d ride at. (Figure 1)
- Next, take a pencil and mark either side of the clamp area, making sure the pencil stays vertical and evenly spaced on either side of the bar. (Figure 2)
- Then, making sure the bar remains at the same angle, make a small line on either side of a point on the grip area. (Figure 3)
- You should now have four marks on the paper.
- Removing your handlebars, plot the middle point of the clamp and rise area on the paper by measuring their width and dividing by two.
- Once you’ve plotted both midpoints, draw a straight line to connect them both using your ruler. (Figure 4)
- From here, draw a horizontal line through the middle point of the clap area, creating your angle. (Figure 5)
- Using your protractor, measure the acute angle created by these lines. This measurement is your handlebar rise.
(Click images below to enlarge)
How to Measure MTB Handlebar Backsweep
- Hold your handlebars on top of your piece of paper in an upright position as if mounted to your bike, maintaining their normal angle. (Figure 1)
- Take your pencil and draw a line on either side of the clamp areas, making sure the pencil remains vertical, and the lines are evenly spaced. (Figure 2)
- Next, draw a line on either side of the grip area at any chosen point, again making sure that your pencil remains vertical and that the bar remains in the same position.
- Once you’ve plotted all four points, find and plot the midpoint of the clamp and grip area by measuring the width across the two lines and dividing by two. (Figure 3)
- Join the two midpoints together using your ruler, making sure the line is straight.
- Next, draw a horizontal line following the midpoint of the clamp area (Figure 4).
- Finally, measure the acute angle created by these lines using your protractor. This angle is your backsweep angle.
3. Handlebar Rise
Another measurement you’ll want to bear in mind when measuring bike handlebars is rise.
As discussed above, handlebar rise is similar to upsweep, but instead determines the distance between the centre of the clamp area and the inside “hoods” on mountain bike handlebars.
Riders enjoy using handlebars with more rise on their mountain bikes as they increase your leverage on your front wheel, which many downhill riders find helpful.
- Lay your handlebars down on a piece of A4 paper.
- Make a mark on either side of the clamp area using a pencil. Make sure the pencil remains vertical while drawing. (Figure 1)
- Draw lines on either side of the “hoods”, where the steep rise angle levels out. (Figure 2)
- Remove the bars and plot the midpoint between both sets of lines.
- With the ruler vertical, draw a line through the midpoint of the clamp area, extending up the paper. (Figure 3)
- Place the ruler horizontally through the hood area midpoint and draw a line that passes through the vertical line. (Figure 4)
- Finally, measure the distance from where the lines overlap down towards the midpoint of the stem clamp area.
- This measurement is your handlebar rise distance.
4. Handlebar diameter
“How to measure mountain bike handlebar diameter” is one of the most popular bar-related questions you’ll see across cycling forums.
When it comes to handlebar diameter, there are two areas that you’ll want to measure when buying a new pair of handlebars or buying handlebar accessories. These are:
The clamp area is the point at the centre of your bars, where the stem attaches to your handlebars.
The grip area is the point at the end of the handlebars that you grip while riding.
Two main handlebar clamp sizes are commonly used by bikes today. These sizes are shown in the table below.
At the bottom of the page, you can view a more detailed table, including the corresponding grip area sizes.
| Handlebar Clamp Size (mm): | Used by: |
|---|---|
| 25.4 | ISO standard size - Used by many MTBs and Road bikes |
| 31.8 | Oversized handlebars - Newer size, becoming popular with both road and mountain bikes |
There are two easy ways to measure handlebar diameter that apply to both mountain and road bars, so I put together a qtwo minute guide at the bottom of this article.
Click here to skip to this section and view several easy ways to measure bike handlebar diameter.
5. Handlebar Weight
Another measurement you might want to take when taking mountain bike handlebar measurements is their weight.
This step is pretty self-explanatory. Stick your handlebars on top of your scales, making sure that the total weight of the handlebar is resting on the scales and no other surface.
Your average mountain bike handlebars weigh between 150 and 400g (0.33 to 0.88lb).
However, handlebar weight varies, depending upon the material they’re made from and their geometry. Some lighter carbon MTB handlebars are available, but these typically cost much more and aren’t necessary for your average mountain biker.
Bear in mind that lightweight isn’t always better. For example, a pair of carbon handlebars may only weigh 150g, but they’re much less durable than pair of steel handlebars and more prone to damage if knocked or dropped.
How to Measure Road Bike Handlebars
Road bike handlebars are narrower than mountain bike handlebars, offering increased aerodynamic performance and multiple hand positions.
But how do you measure drop bars, and what size handlebars do you need for your road bike?
Let’s find out.
1. Handlebar Width
Road bikes are designed to provide good aerodynamic performance, so their handlebars are designed to assist them in their pursuit of speed.
The majority of road bike handlebars sit between 36 – 46cm wide. Which is narrow compared to MTB handlebars.
These measurements represent the distance between the centre the drop on either side of a pair of handlebars.
Most road bike drop bar manufacturers use this sizing method with their handlebars. Manufacturers and brands that use different width measurement methods will normally state or display how they’re measured.
The width of your road bike handlebars will depend upon your riding style and what you want to get from cycling.
If you’re a competitive road racer, a narrower set of drop handlebars will be beneficial as narrower bars reduce aerodynamic drag and allow you to enter a tight tuck position.
However, if you’re a commuter or cyclist that desires a combination of comfort, speed and steering precision, a wider set of road bike handlebars will suit you nicely.
Unlike mountain bike handlebars, you can’t trim drop handlebars to size, so you’ll need to take your measurement before AC measurement to make sure you’re buying the correct size.
Below I’ll explain how to calculate the most suitable width of drop handlebars for you using your AC measurement.
The secret formula when it comes to choosing road bike handlebar width is to start with a pair of handlebars that are the same width as your AC (acromioclavicular) joints in your shoulders.
Your AC joint is the outermost bone on the end of your shoulder, which can normally be seen as a little lump underneath the skin.
Handlebars that mirror the width of your AC joints distribute your weight evenly and provide a comfortable place to start if you’re looking to try a new pair of handlebars.
How to Measure Road Bike Handlebar Width
To measure the width of road bike/drop handlebars, you’ll need a tape measure.
- With your drop bars on the ground, take your tape measure and hold it in the centre of one bar end.
- Pull the tape across to the centre of the opposite bar end.
- Take a reading where the tape crosses the centre of the bar end.
- This measurement is the width of your road bike handlebars.
2. Handlebar Reach
On road bike handlebars, reach is the distance from the centre of the clamp area to the centre of the most forward point of the drop (where the brake hoods are attached).
Essentially this measurement is the distance you’ll have to reach forwards when riding in a tucked position.
Measuring the reach of a pair of road bike handlebars is pretty technical, so for those interested, click here to view a detailed walkthrough at the bottom of the page.
3. Handlebar Drop
On road bike handlebars the drop measurement is the distance between the centre of the clamp area to the centre of the lowest section of the handlebars.
Cyclists use the drops of their handlebars when travelling downhill as it allows them to lower their centre of gravity and establish a firm grip on the handlebars whilst travelling at high speeds.
Additionally, utilising this lower section of drop handlebars provides better aerodynamics, helping to increase your speed while riding.
Measuring the drop on road bike handlebars is another technical faff, so click here to view my easy step by step guide with images at the bottom of the page.
4. Handlebar Diameter
Handlebar diameter is another important measurement you’ll want to take when sizing a new pair of handlebars for your bike.
Just like mountain bike handlebars, you’ll want to take two measurements when taking your drop bar diameter measurements:
The handlebar clamp area is the point at the centre of your bars where the stem attaches
There are two main handlebar clamp sizes that are commonly used by bikes today, these are shown in the table below and here at the bottom of the page alongside some older sizes.
| Handlebar Clamp Size (mm): | Used by: |
|---|---|
| 25.4 | ISO standard size - Used by many MTBs and Road bikes |
| 31.8 | Oversized handlebars - Newer size, becoming popular with both road and mountain bikes |
5. Handlebar Weight
One of the final road bike handlebar measurements you may want to consider is weight.
Many serious road cyclists opt for the lightest components they can get their hands on to increase their efficiency on hill climbs.
Your average pair of road bike drop handlebars weigh between 200 – 400g (0.44 – 0.88lb), although many top-end carbon bars weigh as little as 120g (lb).
To weigh your road bike drop handlebars, stick them on a scale, ensuring that their full weight is on the scales and take your reading.
If you struggle to get your drop handlebars on the scales, use a larger platform to place the bars on top of. Then, make sure to zero the scales before weighing your handlebars.
Most cyclists won’t care how much their handlebars weigh, and unless you’re a veteran competitive cyclist, you’ll struggle to notice the difference between a pair of 150g or 300g handlebars when cycling.
How To Measure Handlebar Diameter (2 Easiest Methods)
The steps below will teach you how to measure the clamp and grip diameter for both mountain bike and road bike handlebars.
Handlebar Clamp Diameter Explained
As previously explained, the handlebar clamp diameter is the total cross-sectional width of the area where the stem attaches to the handlebars.
If you buy handlebars with the wrong clamp size for your stem, they won’t work, so pay attention to the steps below.
Handlebar Grip Area Diameter Explained
The grip area diameter is the cross-sectional width of the section where your hands and the controls of a bike (brake levers, shifters, grips) rest.
Whilst the most common grip area diameter is 23.8mm, some manufacturers still produce different sizes, so it’s worth measuring, following the steps below to make sure.
How to Measure Bike Handlebar Diameter - Caliper Method
Using a caliper to measure the diameter of your handlebars is the easiest and most accurate method.
I understand that most people won’t have access to a caliper, so this method uses a piece of string or paper to achieve the same results.
To measure the clamp area diameter on your bike handlebars, take your caliper and place the widest point of the clamp area inside the caliper’s jaws.
Tighten the caliper, making sure the jaws press flat on opposing sides of the clamp area and take your reading.
Next, to measure the grip area diameter, take your caliper and place it around the area when your hands rest, next to where your brakes attach to your handlebars.
Make sure that the caliper is positioned flat on the grip area surface, tighten the jaws and take a reading of the diameter.
This measurement is, as you might expect, the grip area diameter.
How to Measure Bike Handlebar Diameter - String or Paper Circumference Method
If you don’t have a caliper get yourself a strip of paper or a piece of string, a pen and a ruler/tape measure.
- To measure the clamp or grip area diameter, wrap the paper or string around the centre of the chosen area, making sure there is no slack.
- Then, using the pen, mark the exact point where they overlap.
- Next, using a tape measure or ruler, measure the distance from the end of your piece of paper/string to the marked point.
- This distance is the circumference of the area circumference.
- Finally, to find the diameter of your grip or clamp area divide the circumference by 3.14 (pi).
Bike Handlebar Size Chart
This table displays the different handlebar clamp diameters alongside their corresponding grip diameter.
Take note from the central section that most of these handlebars are no longer in production but are still used by many older bicycles.
| Stem Clamp Diameter | Handlebar Types | Grip Area Diameter | ||
|---|---|---|---|---|
| 22.2mm | 0.874" | Steel bars used by BMX and old MTBs | 22.2mm | 0.874" |
| 23.8mm | 0.937" | (Size no longer used) - Old British road size | 22.2mm | 0.874" |
| 25mm | 0.984" | (Size no longer used) - Old French size | 23.5mm | 0.925" |
| 25.4mm | 1" | I.S.O Size for most flat and riser handlebars | 22.2mm | 0.874" |
| 25.4mm | 1" | I.S.O Size for most drop handlebars | 23.8mm | 0.937" |
| 25.8mm | 0.937" | Italian size for 25.4 & 26mm stems | 23.8mm | 0.937" |
| 26mm | 1.023" | Italian drop bars such as Cinelli | 23.8mm | 0.937" |
| 26.4mm | 1.039" | (Size no longer used) Old Italian bars | 23.8mm | 0.937" |
| 27mm | 1.062" | (Sized no longer used) Titan handlebars | 23.8mm | 0.937" |
| 31.8mm | 1.252" | XL Road Bike Handlebars | 23.8mm | 0.937" |
How to Measure Road Bike Handlebar Reach and Drop
To take the below measurements you’ll need:
- Your drop handlebars
- A pencil
- A ruler
- A sheet of A4 paper
How to Measure Drop Handlebar Reach
- Take your drop handlebars and place them flat on your piece of A4 paper with the clamp area propped up so that bar sits flat or at a similar angle that you ride with (See figure 1)
- Next, take your tape measure and measure the distance from the table to the centre of the clamp area bar. Take note of this measurement. You’ll need it later. (See figure 2)
- Now with the drop bars in the same position, measure the distance from the table to the centre of the highest part of the drop. Take note of this measurement. (See figure 3)
- Now all you need to do to calculate the reach is to subtract your first measurement from step two from the measurement in step three.
- The remaining figure is the reach distance of your drop handlebars.
How to Measure Drop Handlebar Drop
Click any of the images above to enlarge
- Place your handlebars flat on the sheet of A4 paper, propped up underneath the clamp area so that they sit flat or at a similar angle that you ride at. (Figure 1)
- Take your pencil and hold it vertically alongside the clamp area, drawing a small line down either side. (Figure 2)
- Now draw a circle around the bar end that’s touching the paper, holding the bar firmly, so it doesn’t move. (Figure 3)
- Measure the width of the two lines, and you’ve drawn and plot a midpoint between them.
- Keeping your ruler horizontal, extend midsections from the clamp area across the paper. (Figure 4)
- Plot the midpoint of the circle and draw a vertical line down through the centre, keeping going until the two central lines overlap. (Figure 5)
- Finally, using your ruler, measure the distance from the middle of the circle to the overlapping point. (Figure 6)
- This distance is your handlebar drop measurement.
Handlebar & Handlebar Sizes FAQs
Yes, bike handlebars are interchangeable, just make sure that you replace your current handlebars with bars that use the same clamp and grip diameter.
The majority of most modern handlebars have a 31.8mm “oversized” clamp area with a 23.8mm grip area, but there are several other common sizes.
Handlebars don’t all have the same clamp or grip diameter.
Road bike handlebars are typically found with two clamp sizes:
- 26mm – Normally found on older road bikes
- 31.8mm – These “oversized” bars are used by most modern road bikes
Mountain bike handlebars also come with two main clamp sizes:
- 25.4mm – Older mountain bikes and hybrid bikes
- 31.8mm – New mountain bikes use an “oversized” clamp area
Handlebar width depends upon several factors.
If you ride a mountain bike, a good way to estimate the maximum width is to multiply your height (in cm) by 4.4.
For example, 4.4 x 175(cm) = 770. So your maximum recommended handlebar width is 770mm.
For road bike handlebars, your best bet is to choose handlebars that are the same width as your AC (acromioclavicular) shoulder joints.
Road bike drop bars the same width as your AC joints provide a comfortable riding position and allow you to shift between different riding positions without placing strain on your body.
Road bike handlebars vary in diameter, the two most common clamp diameters used by road bikes are:
- 26mm – Used by older road bike handlebars, uncommon on road modern bikes
- 31.8mm – Used by the majority of modern road bike handlebars and is considered to be “oversized”
The majority of mountain bike handlebars use one of two different handlebar clamp sizes:
- 25.4mm – Commonly found on old mountain bikes
- 31.8mm – Most modern mountain bikes use these “oversized” handlebars
Cyclists often ask “do handlebars expire”, or “should handlebars be replaced after a certain amount of use”.
To put it straight, bike handlebars don’t have an expiry date and don’t need to be replaced unless they are damaged or you suspect they are no longer safe for use.
If you use carbon handlebars and have a crash or if they take a knock when you drop your bike, I’d recommend checking them for cracks and signs of damage before riding with them again.
If you’re really concerned that the structural integrity of the carbon has been damaged the coin test is a great way to identify and pinpoint damaged carbon fibre.
Remove the handlebars from your bike and detach all accessories including grips, tape and bar-ends.
Next take a coin and tap it along the handlebars:
- Structurally sound carbon fibre will provide a sharp crisp noise when tapped with a coin.
- Damaged carbon fibre will provide a dull thudding noise
If you find an area on carbon bars that you think’s damaged, I’d recommend replacing them straight away.
Similarly, if you crash with aluminium or steel handlebars and they’re badly damaged or bent, it’s better to be safe and replace them.
Conclusion - How To Measure Bike Handlebars
And there it is! Hopefully, you now understand how to measure bike handlebars, if I’ve missed anything or left any of your questions unanswered, let me know in the comments below, and I’ll get straight back to you with the answers.
Ultimately the best way to find a new pair of handlebars that are the right size is to test out many different sizes.
In this guide, I’ve only covered MTB and road bike handlebars. Read my comprehensive guide if you’re looking to learn more about the many different handlebar types available to you.
Paying for a professional bike fit can also be a great way to find out the best size handlebars for your riding style and body shape.
As always, make sure you’re locking your bike with a good quality lock. There are too many thieves on the prowl to be using a cheap dollar store lock to secure your two-wheeled steed.
If you’re on a tight budget, check out my review of the best cheap bike locks.
Lock it or lose it.
Ciao for now.
Helpful resources:
