Speedplay Aero Zero

Can aero pedals make a difference? We tested the Speedplay Aero Zero pedals to find out if, indeed, aero matters under your shoes.

Aero Tested - Speedplay Aero Zero Pedals

Before we get started, let me make a confession to all of you. I’m a huge fan of Speedplay pedals. I’ve been using them on my bikes since their inception in 1992, and still use X Series pedals today. At ERO, it’s quite common to recommend Speedplay to our clients, though we don’t sell them (maybe we should!). I’ve been interested in testing the Speedplay Zero Aero pedal since it’s unveiling, but testing the aerodynamics of the foot/shoe/pedal interface is not an easy task. I’ll explain the challenge below, but if you really don’t care about such things, scroll down a few paragraphs to see the results of our testing.

In the eyes of the wind, the shoe, cleat, and pedal (let’s just call this the Pedal Interface) isn’t pretty. Most Pedal Interface combinations are bulky and present a significant frontal area that’s churning through the air as we pedal. There’s little doubt that substantial drag is likely created from this area. For instance, certain shoes test more aerodynamic than others, and proper shoe covers can have a positive effect on reducing drag, but not a lot has been done to smooth airflow underneath the shoes when it comes to the pedal interface; certainly nothing has stuck.

Testing the aerodynamics of the Pedal Interface with an actual rider is difficult. For instance, if you wish to test the difference in drag between two competing pedal systems, you’ve created quite a challenge for yourself. First of all, you’ll need to use the same shoes. Not just the same make and model of shoes, but the same shoes. Why? Because no two shoes are exactly alike and will, therefore, test differently from one another. Once you’ve decided to use the same pair of shoes, you need to insure the cleats place the pedal and, therefore, the foot in the exact same position. If you don’t, and you’re going to have a really hard time doing it, the foot will not likely pedal at the same angle which will, in turn, change the frontal area. Heck, tightening the buckles, laces, or boa’s differently can affect the frontal area of the shoe. Any change in the frontal area of the entire pedal interface and you’re no longer measuring the difference in drag between two pedal systems but, instead, the difference between two foot positions.

Speedplay, while asserting the Zero Aero does have an aerodynamic advantage, doesn’t actually claim what the reduction in drag may be. I like that. Maybe they don’t have the data, I know for a fact they understand how difficult it is to test, so instead of giving you pie-in-the-sky numbers, they prefer to make no specific claims. Okay, let’s get to what we found.

Test Riders

  1. Rider #1 – David
    1. Bike: Specialized Shiv TT
    2. Shoes: Sidi Wire SP Carbon (Speedplay Specific)
    3. Pedals: Speedplay Zero vs Zero Aero
    4. Power Meter: PowerTap G3
    5. Weight = 79.4 kilos w/bike
  2. Rider #2 - Leo
    1. Bike: Fuji Track Elite
    2. Shoes: Specialized S-Works 6
    3. Pedals: Speedplay Zero vs Zero Aero
    4. Power Meter: Power2Max
    5. Weight = 85.5 kilos w/bike

Aero test technology: Alphamantis Track Aero System

Location: VELO Sports Center (LA Veldrome)

Protocol: Test riders completed multiple runs with both Zero and Zero Aero pedals. Each run consisted of at least 12 laps. CdA was an average of those laps discarding both highest and lowest recorded lap CdA’s. Non-walkable Zero cleats were used for the Zero pedals. Cleats were exchanged and placed as close as reasonably possible on the same shoes. All pedals had identical spindle lengths.

Speedplay did not provide the product for this testing, nor did they know the testing was taking place. They were informed of the test results prior to publishing this article and provided permission to use photos from their web site. Otherwise, this was a completely independent test.

Both of our test riders had worked with ERO previously and had quite a bit of experience aero testing on the velodrome. This helped produce consistent results for all runs. Each was able to reasonably repeat their drag numbers, which is key for credible results.