Walk into any bike shop and you'll quickly notice that carbon wheels come in a wide range of rim depths. You might see 35mm wheels sitting next to 50mm, 55mm, or even deeper rims.
At first glance, it is tempting to assume that deeper automatically means faster.
The reality is a little more complicated.
Rim depth affects aerodynamics, weight, handling, and even how a bike feels in crosswinds. Choosing the right depth is therefore less about finding the biggest number and more about finding the right balance for your riding.
What Does Rim Depth Actually Do?
A bicycle wheel creates aerodynamic drag as it moves through the air. At higher speeds, aerodynamic drag becomes a significant part of the total resistance a rider has to overcome.
A deeper rim can help control airflow around the wheel and reduce aerodynamic losses.
This is one reason deep-section wheels are so common in racing. When you're riding at high speed on relatively flat roads, maintaining speed efficiently matters.
However, the advantage of a deeper rim doesn't mean every rider should use the deepest wheel available.
Deeper Isn't Always Better
A very deep rim can add weight compared with a shallower design. It can also be more affected by strong crosswinds depending on the wheel's shape, rider weight, tire choice, and weather conditions.
For an everyday rider who spends a lot of time climbing steep roads, a lightweight shallower wheel may feel better.
For someone who rides fast group rides on rolling terrain, a deeper aero wheel may provide a better overall balance.
This is why modern wheelsets often come in several depth options.
The NOVA Road Wheels are offered with rim depths from 35mm through 66mm, allowing riders to choose a configuration based on their preferred balance between aerodynamics, weight, and handling.
Your Typical Speed Matters
Aerodynamics become more important as speed increases.
If your normal rides are mostly relaxed and relatively slow, the aerodynamic difference between wheel depths may not be your biggest concern.
But if you're regularly riding at higher speeds, especially in a group, racing, or riding long stretches of flat road, aerodynamic efficiency becomes increasingly relevant.
This is also why wheel upgrades can feel more noticeable on fast roads than on steep climbs.
You may not immediately notice a difference during a short uphill section, but holding speed on a flat road for several miles can make the benefits easier to appreciate.
Crosswinds Are Part of the Equation
One of the biggest concerns riders have with deep wheels is crosswind stability.
A deeper rim presents a larger surface to the wind. However, rim depth alone doesn't determine how stable a wheel will feel.
The rim shape, external width, tire size, rider weight, wind direction, and speed all influence handling.
Modern aerodynamic wheels are designed with these factors in mind. The goal is not simply to make the wheel deeper, but to manage airflow in a predictable way.
For everyday riders, this is one reason a balanced aerodynamic wheel can make more sense than an extreme time-trial setup.
Don't Forget Tire Width
Wheel and tire compatibility has become increasingly important as road bikes move toward wider tires.
A modern road setup might use 28C, 30C, or 32C tires rather than the narrow tires that were common a decade ago.
The internal width of the rim affects the shape and support of the tire. The right combination can improve handling while also allowing the tire to perform as intended.
The NOVA's 23mm internal width is designed around 28–36C tires, making it a versatile option for modern road setups.
What About Gravel?
Gravel riders face a different set of requirements.
Aero performance can still matter, particularly in gravel racing, but riders also need enough tire volume and stability for unpaved surfaces.
This is where wider rims become particularly useful.
The VELO 50 Gravel Wheels combine a 50mm deep profile with a 29mm internal width and compatibility with 34–56C tires.
That approach is aimed at riders who want aerodynamic performance without giving up the wider tires needed for gravel.
Choosing the Right Depth
A simple way to think about rim depth is this:
Choose shallower wheels if you prioritize climbing, low weight, and an easy-to-handle setup.
Choose medium-depth wheels if you want an all-around balance.
Choose deeper wheels if you regularly ride fast roads, race, or spend a lot of time trying to maintain high speeds.
For gravel, consider rim depth together with internal width and tire size rather than looking at depth alone.
The fastest wheel isn't necessarily the deepest one. It's the one that gives you the best combination of aerodynamics, weight, stability, and compatibility for the riding you actually do.
