Without a doubt, there is a lot of information to wade through when trying to decide which aero wheels will perform best for your style and level of riding.
Let’s start first with some basic definitions.
Profile – the depth of a rims cross section, measured from top of sidewall to spoke face
Width – at ENVE we are generally measuring the rim at its widest point, most commonly the outer width on the braking surface
Stability – the manner in which a wheel reacts to inputs from the airflow
Drag – refers to the friction created from the air flowing over the rim…less is better
Now, let’s talk about what makes the best aero wheel.
Aerodynamics – This is a very technical subject but to put it simply, the more aero the wheel the faster you can go at any given power output. There are many ways to optimize a rim shape to be aerodynamic but for a wheel, it must be considered as a complete system within a bicycle frame and fork. The frame and fork affect how the air moves around the shape of the rim, therefore development must happen within a bicycle frame. Consequently, this is also the only way you can use a wheelset which leads us to the next topic.
Real World Performance – The real world in which we ride is a dynamic environment. A wheel that performs well in the windtunnel is often discovered to be unrideable in the real world. Why is this you ask? Because wind tunnels, while integral to wheel development, are a static environment and only tell us a fraction of the overall performance story. Therefore, it is imperative that a wheelset be stable and predictable when managing the ever changing airflow that you confront during every ride. Real world optimized means that the wheel is ultimately faster from point A to B no matter what the weather conditions are. In virtually all real world racing and riding scenarios being mentally calm, confident, and in control on your bike is a larger advantage than riding a wheelset promised to save X amount of watts derived from testing wheel only in the windtunnel. Therefore, until dynamic environments can be replicated in a meaningful fashion within windtunnels the final test of a wheels proficiency must be performed on the road.
Asymmetric Rim Geometry Front to Rear – For a moment consider a few things in the world that are designed and optimized to travel through air or water like airplanes, boats, and race cars. Each of these vehicles is shaped very differently from front to back. Why? Because airflow interacts with the front and back regions in a unique fashion. Triathlon race bikes like the Cervelo P5 are no different, and neither are wheels. If you are looking to purchase a set of aerodynamic race wheels, they must be different shapes front to back or you are leaving efficiency and speed on the table.
Structural Considerations – Sound real world aerodynamics will only get you as far as the wheel’s construction and design will allow. If the wheel is heavy or poorly constructed efficiency suffers or you don’t finish your race. Simply molding carbon fiber in a aero rim shape does not mean it will be a fast and efficient wheel. With carbon you get what you pay for, the best carbon rims will be optimally light, stiff, durable and highly reliable. You invest heavily to succeed in racing triathlon, don’t compromise that investment riding a carbon wheelset that doesn’t check off all the selection criteria listed above. At ENVE we don’t believe in race day wheels, we believe your best wheels should be ridden every day and we back this belief by investing in US manufacturing and offering an unprecedented warranty policy. You can learn more about what sets ENVE apart by visiting Why ENVE.
Application Oriented – Different rim profiles and geometries exist because aero wheels are not a one size fits all application. Because rider experience, preferences, bikes, and course profiles vary, picking the best wheel for you requires investigating each manufacturers intended application for a given wheel.
The following is an application guide for the Smart ENVE System.
The SES 3.4 is a multi-purpose road wheel with an aero advantage
Overview – The SES 3.4 is a great choice for athletes who are new to the sport and seeking maximum weight savings and stability. Having a lightweight and easily manageable wheel set in strong wind conditions means that novice cyclists can ride with more confidence and come off the bike fresh and ready to run.
The SES 4.5 is the first in the next generation of SES wheels, less depth and more speed
Overview – The SES 4.5 is optimized for modern frame design and tire sizes. As such, the SES 4.5 performs best when paired with a 25mm tire. Advancements in SES technology have allowed us to
create a wheel that is shallower and faster (when paired w/ a 25mm tire) than our venerable SES 6.7 wheelset and lighter and more stable than the popular SES 3.4. This is truly the best choice for rolling to hilly triathlon courses and for novice or light weight riders looking for maximum control and confidence in gusty wind conditions.
The SES 6.7 is a jack of all trades triathlon wheel set
Overview – The SES 6.7 is by far the most prolific SES wheel in triathlon. With a 60mm deep front wheel and 70mm deep rear wheel the 6.7 is easily managed by intermediate and experienced cyclists over rolling terrain with strong and gusty crosswinds. The 6.7 is the most common wheel choice of ENVE athletes year over year in Kona for these reasons.
The SES 8.9 sets the bar as fastest wheel against the clock
Overview – The SES 8.9 is for experienced to professional triathletes looking for the maximum amount of drag reduction and speed. Despite its depth the 8.9 is still very stable and predictable in strong wind conditions, but riders with many years of experience racing triathlon and long hours in the aero bars will be most comfortable with the fastest aero carbon clincher on the road.