Reducing Tradeoffs - The SES 4.5
REDUCING TRADEOFFS – THE SES 4.5
MAY 29TH, 2015
The Smart ENVE System 4.5 (SES 4.5) ushers in the next generation of in-frame aero wheel development. Featuring a new shape and refined structure, the SES 4.5 reduces the trade-offs between drag reduction and stability, stiffness and weight, comfort and durability more than any other ENVE wheelset to date.
New SES Shape = More Speed and Stability
The patented SES rim shape (patent # US 8,757,733155) features a sidewall curvature that allows the airflow to remain attached to the rim over a broad range of wind angles while allowing side-force to build and release in a predictable manner. The success of the SES rim design is based in approaching aero wheel development from the perspective that wheels, fork, frame, and rider create a complete system. Each variable affects the other and therefore must be given equal consideration throughout the development process in order to ensure the system reaches maximum performance potential.
The new shape of the SES 4.5 rivals the aero performance of the SES 6.7 at roughly the same weight as the SES 3.4
The SES 4.5 is the beginning of the evolution from the original Smart ENVE System. Tested and optimized in the Mercedes GP Petronas Wind Tunnel the SES 4.5 is the fastest rim on the market when tested on a modern aero road or triathlon frame and compared to rims of a similar depth. The new shape of the SES 4.5 is wider than previous SES models to improve aero performance in modern bicycle frames and to improve ride characteristics when paired with tires between 24mm and 26mm wide depending on your tire brand of choice.
When compared to the existing line of SES wheels, the 4.5 essentially matches the aero performance of the SES 6.7 which is a much deeper rim at 60mm in the front and 70mm in the back.
SES Wheelset Comparison on Scott Foil with 23mm Continental CP 4000 @ 50kph
The aero performance achieved with the SES 4.5 is accomplished by adjusting the rim shape to focus on airflow recovery downstream in the system. In addition to the reduction in drag, the new SES 4.5 is also more stable than any previous SES wheel model. With the new rim shape comes superb straight-line tracking and handling characteristics for a confident ride in strong and gusty wind conditions.
Improved Structure and Braking Performance
The aerodynamically efficient shape of the SES 4.5 is supported by a backbone of structural improvements that allow this rim to be the most heat and impact resistant road rim we’ve produced to date.
Through the application of our molded-in brake track technology and refined carbon fiber laminates, we have been able to increase the heat resistance of the SES 4.5 by roughly 30% over the previous SES models.
Brake track testing during the qualification of the Smart ENVE System 4.5
In addition to the improvements made to braking and impact performance, the SES 4.5 is light weight and more laterally stiff than previous SES wheel models. The combination of reduced weight and increased lateral stiffness results in snappy accelerations and confident handling in technical corners at speed. Each SES 4.5 rim set weighs in at a mere 60 grams heavier than the lightest SES wheelset the 3.4 making the SES 4.5 an excellent choice as a multi-purpose one wheelset quiver. For this reason and those listed above Team MTN-Qhubeka p/b Samsung used the SES 4.5 as their primary wheelset for racing on the World Tour stage.
The full carbon SES 4.5 is all about reducing trade-offs between weight and stiffness, aerodynamics and stability. The SES 4.5 displays the highest stiffness to weight ratio in the Smart ENVE System aero wheel line.
Conclusion
As we continue to develop wheels in the context of a complete system made up of frame, wheels, and rider, the real world performance of the wheels will continue to help road cyclists ride faster and optimize their ride experience. Offering similar aero performance of the venerable SES 6.7 at roughly the weight of the ever popular SES 3.4 model road wheels, the SES 4.5 is a one-wheel quiver and the beginning of the next level performance that will be achieved as we introduce new models to the next generation Smart ENVE System.
Developing the SES 4.5 in ENVE’s backyard.