If you’ve got a time trial bike with disc brakes, ENVE’s SE 7.8 Disc Tubeless Wheelset is looking to be your go-to go-fastest wheel.
SES is short for Smart ENVE System, which is both smart and designed by Simon Smart, an aerodynamicist who has consulted with ENVE. Look him up. He has a long resume of aero success. 7.8 refers to the differential rim depths, 71mm for the front and 78mm for the rear. Smart found that rim depths and shapes should be different front and rear as they experience the wind differently. Here, the front is 71mm deep, 29mm wide, and weighs 514g. The rear is 78mm deep, 27.5mm wide and weighs 549g. Both have an internal channel 19mm wide and are optimized for 25mm tires, though 23-28mm tires will fit.
As with other ENVE disc-specific rims, they built the rim specifically for disc-brake wheels. Because of this, they were able to save considerable weight at the rim, particularly the area where the brake track used to be, and still have a strong rim.
The rims are also tubeless compatible. You don’t have to install tubeless tires, but they’re ready if you want to. The rim wall height and internal shape has been designed to work with tubeless and the wider rims make tubeless tires easier to install.