Like the rest of the SES line, the 4.5s' rims aren't subjected to static, arbitrary widths and shapes. Instead, the engineers let each wheel's depth requirements dictate the ideal dimensions in order to reduce lateral forces and increase aerodynamic benefits across a wide range of yaw angles. The 4.5s' design also accounts for the different behaviours of front and rear wheels. The front wheel is 48 millimetres deep and 27 millimetres wide, while the rear wheel is deeper and skinnier at 56 millimetres deep and 25.5 millimetres wide. This decreases drag with a focus on increased stability up front while taking advantage of the fact that the aft position has less of an effect on stability to focus on aerodynamic gains in the rear.
The result is that the 4.5 handles crosswinds and gusts with the confident stability of a wheelset with half its depth by building up a side-force equal to the changing angle of the wind. While this sounds like so much marketing palaver, it's verified by a Stability Index. ENVE borrows this testing protocol from the Formula One industry, and it remains the only cycling manufacturer with the confidence to measure its wheels by such a demanding metric.
To rate a wheelset on this index, the front wheel is subjected to quick changes in wind degree at set yaw angles, and the steering torque of user-correction is then measured. This means you won't be thrown across the road when a sharp turn radically changes your orientation to the wind, and you'll also enjoy more stability in gusty conditions, eliminating unfortunate surprises while cruising in the bunch.
Of course, we also recognize that aerodynamics are absolutely meaningless if a wheelset crumbles at the first sign of less-than-optimal road conditions, so we expect ENVE's obsessive engineering to carry over into the wheels' materials and layup. Knowing that carbon gains strength from continuously wrapped fibres, we're happy to report that ENVE routes the fibres around each hole in a 100% intact design, which adds strength, boosts rigidity, and allows for less material and a lighter rim. The use of a removable bladder also keeps weight down compared to other wheels. This means the SES series boasts the highest claimed strength-to-weight ratio on the market.
Finally, it's worth noting that the 4.5s' generous interior widths grant your tires a lower rolling resistance at a lower PSI, so you can enjoy a ride that's both faster and more comfortable. The tires will also deform less while cornering, so they'll keep a better grip on the road and let you carry more speed through turns. The wheels are finished with the Chris King R45 hub.
• Wheel Size: 700c
• Tire Type: Clincher
• Rim Depth: [front] 48 mm, [rear] 56 mm
• Rim Width: (external) [front] 27 mm, [rear] 25.5 mm
• Brake Compatibility: Caliper
• Hubs: Chris King R45
• Ceramic Bearings
• Spokes: DT Swiss Aerolite
• Spoke Count: 20/24
• Claimed Weight: 1511g
• Manufacturer Warranty: 5 years
• ENVE skewers
• ENVE carbon specific brake pads
• ENVE valve extenders
• ENVE rim tape