PowerTap

GS ENVE SES 3.4 Powermeter Tubular Wheelset

Wheels with power meter hubs often get relegated to a life as dedicated training hoops due to sacrifices in weight and stiffness, which means losing precious data when race day rolls around and you're out hammering on those less science-minded carbon rims. The PowerTap GS ENVE SES 3.4 Powermeter Tubular Wheelset lets you have the best of both worlds, pairing PowerTap accuracy with top-end ENVE carbon in a race-ready wheelset that will track every effort you put into the pedals.

The rims of this wheelset are identical to those found on the standard ENVE SES 3.4 carbon tubs. They're the result of the same collaboration between aero-engineering legend Simon Smart and ENVE Composites, and they represent the latter's most sophisticated technology and engineering techniques. The 3.4's aerodynamic design starts with the size differential of the wheels. ENVE accounted for the different behaviors of front and rear wheels and designed the 3.4s with a front wheel that's 35mm deep and 26mm wide, while the rear wheel is 45mm deep and 24mm wide. This differential decreases overall drag while increasing stability up front. It also takes advantage of the fact that the aft position has less of an effect on steering stability to eke out aerodynamic gains in the rear.

The SES 3.4 rims aren't just aerodynamic; they're also light, stiff, and strong. The ENVE SES series boasts the highest strength-to-weight ratio on the market, which is due in part to ENVE's patented process of molding — rather than drilling — spoke holes, nipple seats, and valve stem holes. The company also invests the time and money in removing the internal mold, making for lower weight and increasing structural integrity. This means that when you combine the hand-built ENVE carbon tubular hoops with the new PowerTap GS hubs, it adds up to one of the lightest and stiffest carbon PowerTap tubular wheelsets ever produced.

On the power meter side, PowerTap partnered with DT Swiss to create its GS line of hubs. The "S" in the title stands for "straight-pull" and as you would expect, the spokes on the hub are indeed straight-pull. The electronics are identical to the G3 hub and the caps are interchangeable, but the body itself looks completely different because it's essentially DT Swiss' 240 hub — complete with the brand's signature star ratchet engagement system and stainless bearings.

Like the G3, the GS's electronics are built into the end cap, so if you have wheel-based power reading problems, you're able to send just the cap back rather than your whole wheel. Additionally, it is powered by a single CR2032 battery, which is easier to source than the two 357 batteries in older hubs. Each battery lasts for about 300 hours of riding, and the hub communicates power data with an ANT+ transmitter so most head units are already able to read and display the metrics. The hub's eight strain gauges yield power measurements within +/- 1.5% accuracy — on par with the industry standard because PowerTap pretty much is the industry standard.