Road bikes use drop-bar handlebars, which impact where your arms rest and the position of your body as you ride. However, the style also changes how you measure the handlebars to get the proper fit.
Good high-quality handlebars of the right size make a significant difference in aerodynamics and comfort for the rider. How are road bike handlebars measured?
You measure road bikes handlebars by reach width and drop. Reach is the distance from the center of the handlebar at the stem to the bend, and drop is measured from the distance between the flat top section of the bar to the lowest point on the handles’ downward curve (drop). Width is the horizontal measurement from the center of one handlebar to the other.
Recommended Gear
To see all of my up-to-date recommendations for bikes and cycling gear, check out this resource that I made for you!
Table of Contents
How To Measure Handlebar Size On Road Bike
Measuring your current or future handlebars is a valuable skill. A slight variation in the reach or drop can make a big difference.
From faster speeds to pulled muscles, it may surprise you how critical it is to have the right fit for your bike and body.
Below is a step-by-step list of how to measure handlebar size on your road bike:
- Find the reach. You need first to locate the center of the handlebar at the stem. This means the mid-point in the tube, neither on top of nor below the bar.
- Next, you need to find the center point, but this time it should be the one on the leading edge of the bend. So you don’t want the spot in front or behind the tube, but rather an imaginary dot right in the middle.
- Draw an imaginary line straight up from these two centers and measure the distance in millimeters between them to get the reach. It should be roughly 80 to 85 millimeters.
- Now you need to know the drop. Fortunately, you will start at the same beginning point in the center of the handlebar at the stem.
- Move straight down from there to the center of the bar at the lowest point on the bottom of the drop curve. The distance between the 2 points is the drop.
Pro Tip: Some drops are considered deep. These are generally 130 millimeters or more. Meanwhile, other drops, those under 125 millimeters, are called shallow. If you are new to road bike riding, you may want to begin with a shallow ergonomic drop handle.
Drop Bar Size Chart
Drop bar handlebars for road bikes come in numerous size combinations. You can get thousands of possible combinations from relatively few variables.
Below I’ve created a chart of the variations to help you understand drop-bar sizes and find the best match for you.
Common Drop Bar Sizes
Drop | Reach | Width |
Shallow: 125 mm or less | Short: 80 mm or less | 38 cm |
Medium: 125-129 mm | Medium: 80-85 mm | 40 cm |
Deep: 130 and above | Long: Over 85 mm | 42 cm |
N/A | N/A | 44 cm |
Road Bike Handlebars Types
You can technically put any handlebars you want on a bike, but for road bikes, the type that matters are drop bars.
That said, there are a few variations of drop bars to be aware of. Classic drop bars were often larger and broader, but the modern trend is for a smaller bar.
The smaller, compact handlebars are meant for every day, non-competitive riders. The size and setup of these bars are a little easier on the body, offering greater comfort.
Plus, the shallower drop means your brake leverage is maximized when descending, which is safer for the rider and any traffic sharing the road.
The other significant variation within the drop handlebar spectrum is classic versus ergonomic drops. Classic drops look like a near-perfect U shape turned on its side.
Meanwhile, the more ergonomic drops are angled downward in a slope which is easier on the wrists and hands.
Vintage Road Bike Handlebar Size
There’s only a slight difference between classic or ‘vintage’ road bike handlebars and the modern style.
However, it is certainly noticeable when you lay them side by side. The older style is typically 25.4 millimeters, and the newer handlebars are 31.8, more than 5 millimeters larger.
If you buy a vintage road bike, the more contemporary or oversized handlebars won’t fit properly.
How To Measure Handlebar Width On Road Bike
You’ve already learned how to determine the reach and drop on your handlebars, so now I’ll show you how to measure the width. This is so easy you won’t believe it.
To measure the width of your road bike handlebars, you will need a measuring tape and your handlebars.
Follow the steps below to calculate your width.
- Set the handlebars on the ground or a tabletop facing up so it’s resting in virtually the same position it would on your bike.
- Find the middle of the bars at the widest point. You need to measure from the center of the bar. Don’t place your tape measure on the inside or outside edge of the bars, but rather right in the middle.
- The distance from the center of one drop to the center of the other at the widest point is the width of your handlebars.
Pro Tip: If you are unsure where to start size-wise, get handlebars that are the same width as your shoulders or a little wider. Road Biker says, “The standard fitting advice is to get a handlebar as wide as the measurement between your AC joints. Those are the bumps atop your shoulders where the collarbone attaches just inboard of your deltoid muscle. But many riders prefer a handlebar slightly wider than their shoulders. A wide bar opens the chest. Some people say they breathe better because of it.”
Narrow vs Wide Road Handlebars
Although conventional wisdom tells you to get drop handlebars for your road bike that are the same distance apart as your shoulders, not every rider agrees.
There are advantages to selecting more narrow or wider bars. Ultimately it’s up to you to determine your comfort level.
Narrow Handlebars
Choosing a slightly narrow handlebar can increase your speed. Especially on long rides, a slimmer profile is more aerodynamic.
While you don’t want to put your hands too close together, this slight adjustment can decrease your racing or endurance riding time.
The downside to a narrow handlebar is trading speed for handling. The closer you set your hands, the less control you will have as you ride.
On a long, straight road with little to no wind, it won’t matter, but everywhere else, it helps to have better control. Narrow handlebars are not suitable for beginners.
Wide Handlebars
A wider handlebar can help get better control over your road bike. By opening up the chest and setting the hands wider, the rider can essentially fine-tune their movements to get more accurate bicycle motion.
You will breathe easier and probably be more comfortable with wide bars. The only downside is that you’re sacrificing speed since making yourself broader means more air resistance as you move forward.
If you want a better visual of the differences, this video can help you see the differences. GCN Tech makes exceptional cycling videos, and they offer great tips on choosing the correct handlebars for you.
Helpful Tips To Know About How Road Bike Handlebars Are Measured
Picking the wrong handlebars can be a literal pain, plus it could slow you down and even make your bike less stable. There’s more to drop handlebars than meets the eye.
Here are a few more helpful tips to know about how road bike handlebars are measured.
- Road bike drop handlebars offer a rider three distinct hand positions. By varying your grip, it can help prevent hand pain, increase your aerodynamics or help maximize your power output as you pedal. It’s essential to learn how and when to use each position.
- Drop bars’ width is measured in centimeters. Typically they go up by two at a time, and all the numbers are even. The only time this isn’t the case is if you’ve had custom bars made to fit one rider.
- The only difference between a regular and ergonomic drop bar is whether the bottom of the drop is horizontal or a slight diagonal. The diagonal is easier on your wrists.
Final Thoughts
Knowing how road bike handlebars are measured can help you get a smoother ride. The correct width affects how aerodynamic you are and how much control you have.
Meanwhile, the drop and whether your handles are ergonomic can help you avoid hand cramps as you ride.
Finally, the reach is how far forward the front of your bars sits, and this can help make your bike feel longer.
Good, well-fitted drop bars keep your ride comfortable and help you manage your speed and breathing as you ride.