How to Compare Wind Tunnel Data for Different Wheelsets

Understanding Aero Testing, Key Metrics, and How to Read the Numbers Correctly

When shopping for a new carbon wheelset, many cyclists come across wind tunnel test results proudly presented by brands to showcase aerodynamic performance. But how can you really compare wind tunnel data from different wheelsets—and more importantly, from different manufacturers?

Wind tunnel testing is valuable, but the data can be misleading if you don’t know what to look for.

This guide will teach you how to critically analyze wind tunnel results and make smarter, more informed choices.

Why Wind Tunnel Data Matters for Wheelsets

Wind resistance is the dominant force working against you at speeds above 25 km/h.
Even small aerodynamic improvements in your wheels can save you significant watts and time over long rides and races.

That’s why brands heavily focus on drag reduction (measured as CdA or drag area) when promoting their wheelsets.

What to Look for in Wind Tunnel Reports

1. Yaw Angle Range

Yaw angle refers to the angle of crosswind hitting the wheel.

A good wind tunnel test should include drag data across 0° to 20° yaw angles.

Real-world riding often happens between 5° to 15° yaw, especially in crosswinds.

Key Tip:
Look for wheelsets that perform well across a wide yaw range, not just at 0°.

2. Consistency Across Yaw Angles

Some wheels perform well in head-on wind (0°) but perform poorly in side winds.

What You Want:
Wheels with a smooth drag curve across yaw angles typically offer better real-world stability and predictable performance.

3. Test Conditions Must Match

Rider or No Rider: Some tests are done with a full bike and rider, others with just the wheel.

Tire Type and Width: Wider tires (like 28C) can dramatically affect drag.

Speed: Drag forces scale with speed; some tests use 30 km/h, others use 50 km/h.

Key Tip:
Only compare wind tunnel data when test setups are similar. Data from different conditions isn’t directly comparable.

4. Published Watt Savings

Brands often advertise watt savings at specific yaw angles or speeds.

What to Watch:
If a wheel saves 5 watts at 40 km/h, that’s meaningful.
But if that saving only occurs at extreme yaw angles (15-20°) which rarely happen, the real-world impact may be minor.

5. Independent vs. Brand-Sponsored Tests

Brand-Sponsored Tests: May selectively present favorable data.

Independent Tests: Generally more neutral, though still not perfect.

Look for:
Third-party reviews, magazines, or trusted cycling websites that compare multiple brands under identical conditions.

Common Mistakes When Reading Wind Tunnel Data

Assuming All Tests Are Equal: Test protocols vary by manufacturer.

Ignoring Stability: Lower drag is great, but wheels that are unstable in crosswinds may feel dangerous.

Overvaluing Small Differences: A 1-2 watt difference between wheels is often negligible in real-world riding.

Quick Checklist for Comparing Wind Tunnel Data

Factor	What to Check
Yaw Angles	Minimum range: 0° to 15°
Speed	Was it tested at your typical riding speed?
Tire Setup	Same width, brand, and type?
Rider Included	Was a bike and rider used in testing?
Source	Brand vs. third-party testing?
Real-World Stability	Crosswind performance discussed?

Final Thoughts

Wind tunnel data can help you make smart wheelset decisions—if you know how to read it critically.
Focus on consistent performance across yaw angles, realistic test setups, and practical watt savings.

At Superteam, we test our wheels across a full yaw range and in conditions that mirror real-world riding—not just lab-perfect scenarios. If you need help interpreting wind tunnel results for your next wheelset upgrade, we’re always here to assist.